Programs & Examples On #Rel

The rel attribute specifies the relationship between the current document and the linked document

How to get AIC from Conway–Maxwell-Poisson regression via COM-poisson package in R?

I figured out myself.

cmp calls ComputeBetasAndNuHat which returns a list which has objective as minusloglik

So I can change the function cmp to get this value.

Monitoring the Full Disclosure mailinglist

Two generic ways to do the same thing... I'm not aware of any specific open solutions to do this, but it'd be rather trivial to do.

You could write a daily or weekly cron/jenkins job to scrape the previous time period's email from the archive looking for your keyworkds/combinations. Sending a batch digest with what it finds, if anything.

But personally, I'd Setup a specific email account to subscribe to the various security lists you're interested in. Add a simple automated script to parse the new emails for various keywords or combinations of keywords, when it finds a match forward that email on to you/your team. Just be sure to keep the keywords list updated with new products you're using.

You could even do this with a gmail account and custom rules, which is what I currently do, but I have setup an internal inbox in the past with a simple python script to forward emails that were of interest.

I am receiving warning in Facebook Application using PHP SDK

You need to ensure that any code that modifies the HTTP headers is executed before the headers are sent. This includes statements like session_start(). The headers will be sent automatically when any HTML is output.

Your problem here is that you're sending the HTML ouput at the top of your page before you've executed any PHP at all.

Move the session_start() to the top of your document :

<?php    session_start(); ?> <html> <head> <title>PHP SDK</title> </head> <body> <?php require_once 'src/facebook.php';    // more PHP code here. 

How much should a function trust another function

Typically this is bad practice. Since it is possible to call addEdge before addNode and have a NullPointerException (NPE) thrown, addEdge should check if the result is null and throw a more descriptive Exception. In my opinion, the only time it is acceptable not to check for nulls is when you expect the result to never be null, in which case, an NPE is plenty descriptive.

Using Lato fonts in my css (@font-face)

Well, you're missing the letter 'd' in url("~/fonts/Lato-Bol.ttf"); - but assuming that's not it, I would open up your page with developer tools in Chrome and make sure there's no errors loading any of the files (you would probably see an issue in the JavaScript console, or you can check the Network tab and see if anything is red).

(I don't see anything obviously wrong with the code you have posted above)

Other things to check: 1) Are you including your CSS file in your html above the lines where you are trying to use the font-family style? 2) What do you see in the CSS panel in the developer tools for that div? Is font-family: lato crossed out?

Uninitialized Constant MessagesController

Your model is @Messages, change it to @message.

To change it like you should use migration:

def change   rename_table :old_table_name, :new_table_name end 

Of course do not create that file by hand but use rails generator:

rails g migration ChangeMessagesToMessage 

That will generate new file with proper timestamp in name in 'db dir. Then run:

rake db:migrate 

And your app should be fine since then.

Adding a UISegmentedControl to UITableView

   self.tableView.tableHeaderView = segmentedControl; 

If you want it to obey your width and height properly though enclose your segmentedControl in a UIView first as the tableView likes to mangle your view a bit to fit the width.

enter image description here enter image description here

How to make a variable accessible outside a function?

$.getJSON is an asynchronous request, meaning the code will continue to run even though the request is not yet done. You should trigger the second request when the first one is done, one of the choices you seen already in ComFreek's answer.

Alternatively you could use jQuery's $.when/.then(), similar to this:

var input = "netuetamundis";  var sID;  $(document).ready(function () {     $.when($.getJSON("https://prod.api.pvp.net/api/lol/eune/v1.1/summoner/by-name/" + input + "?api_key=API_KEY_HERE", function () {         obj = name;         sID = obj.id;         console.log(sID);     })).then(function () {         $.getJSON("https://prod.api.pvp.net/api/lol/eune/v1.2/stats/by-summoner/" + sID + "/summary?api_key=API_KEY_HERE", function (stats) {             console.log(stats);         });     }); }); 

This would be more open for future modification and separates out the responsibility for the first call to know about the second call.

The first call can simply complete and do it's own thing not having to be aware of any other logic you may want to add, leaving the coupling of the logic separated.

Method Call Chaining; returning a pointer vs a reference?

Since nullptr is never going to be returned, I recommend the reference approach. It more accurately represents how the return value will be used.

Jquery assiging class to th in a table

You had thead in your selector, but there is no thead in your table. Also you had your selectors backwards. As you mentioned above, you wanted to be adding the tr class to the th, not vice-versa (although your comment seems to contradict what you wrote up above).

$('tr th').each(function(index){     if($('tr td').eq(index).attr('class') != ''){         // get the class of the td         var tdClass = $('tr td').eq(index).attr('class');         // add it to this th         $(this).addClass(tdClass );     } }); 

Fiddle

How can I tell if an algorithm is efficient?

Yes you can start with the Wikipedia article explaining the Big O notation, which in a nutshell is a way of describing the "efficiency" (upper bound of complexity) of different type of algorithms. Or you can look at an earlier answer where this is explained in simple english

Implement specialization in ER diagram

So I assume your permissions table has a foreign key reference to admin_accounts table. If so because of referential integrity you will only be able to add permissions for account ids exsiting in the admin accounts table. Which also means that you wont be able to enter a user_account_id [assuming there are no duplicates!]

Xml Parsing in C#

First add an Enrty and Category class:

public class Entry {     public string Id { get; set; }     public string Title { get; set; }     public string Updated { get; set; }     public string Summary { get; set; }     public string GPoint { get; set; }     public string GElev { get; set; }     public List<string> Categories { get; set; } }  public class Category {     public string Label { get; set; }     public string Term { get; set; } } 

Then use LINQ to XML

XDocument xDoc = XDocument.Load("path");          List<Entry> entries = (from x in xDoc.Descendants("entry")             select new Entry()             {                 Id = (string) x.Element("id"),                 Title = (string)x.Element("title"),                 Updated = (string)x.Element("updated"),                 Summary = (string)x.Element("summary"),                 GPoint = (string)x.Element("georss:point"),                 GElev = (string)x.Element("georss:elev"),                 Categories = (from c in x.Elements("category")                                   select new Category                                   {                                       Label = (string)c.Attribute("label"),                                       Term = (string)c.Attribute("term")                                   }).ToList();             }).ToList(); 

Instantiating a generic type

You basically have two choices:

1.Require an instance:

public Navigation(T t) {     this("", "", t); } 

2.Require a class instance:

public Navigation(Class<T> c) {     this("", "", c.newInstance()); } 

You could use a factory pattern, but ultimately you'll face this same issue, but just push it elsewhere in the code.

Does the target directory for a git clone have to match the repo name?

Yes, it is possible:

git clone https://github.com/pitosalas/st3_packages Packages 

You can specify the local root directory when using git clone.

<directory> 

The name of a new directory to clone into.
The "humanish" part of the source repository is used if no directory is explicitly given (repo for /path/to/repo.git and foo for host.xz:foo/.git).
Cloning into an existing directory is only allowed if the directory is empty.


As Chris comments, you can then rename that top directory.
Git only cares about the .git within said top folder, which you can get with various commands:

git rev-parse --show-toplevel git rev-parse --git-dir 

How to create a showdown.js markdown extension

In your last block you have a comma after 'lang', followed immediately with a function. This is not valid json.

EDIT

It appears that the readme was incorrect. I had to to pass an array with the string 'twitter'.

var converter = new Showdown.converter({extensions: ['twitter']}); converter.makeHtml('whatever @meandave2020'); // output "<p>whatever <a href="http://twitter.com/meandave2020">@meandave2020</a></p>" 

I submitted a pull request to update this.

Difference between opening a file in binary vs text

The most important difference to be aware of is that with a stream opened in text mode you get newline translation on non-*nix systems (it's also used for network communications, but this isn't supported by the standard library). In *nix newline is just ASCII linefeed, \n, both for internal and external representation of text. In Windows the external representation often uses a carriage return + linefeed pair, "CRLF" (ASCII codes 13 and 10), which is converted to a single \n on input, and conversely on output.


From the C99 standard (the N869 draft document), §7.19.2/2,

A text stream is an ordered sequence of characters composed into lines, each line consisting of zero or more characters plus a terminating new-line character. Whether the last line requires a terminating new-line character is implementation-defined. Characters may have to be added, altered, or deleted on input and output to conform to differing conventions for representing text in the host environment. Thus, there need not be a one- to-one correspondence between the characters in a stream and those in the external representation. Data read in from a text stream will necessarily compare equal to the data that were earlier written out to that stream only if: the data consist only of printing characters and the control characters horizontal tab and new-line; no new-line character is immediately preceded by space characters; and the last character is a new-line character. Whether space characters that are written out immediately before a new-line character appear when read in is implementation-defined.

And in §7.19.3/2

Binary files are not truncated, except as defined in 7.19.5.3. Whether a write on a text stream causes the associated file to be truncated beyond that point is implementation- defined.

About use of fseek, in §7.19.9.2/4:

For a text stream, either offset shall be zero, or offset shall be a value returned by an earlier successful call to the ftell function on a stream associated with the same file and whence shall be SEEK_SET.

About use of ftell, in §17.19.9.4:

The ftell function obtains the current value of the file position indicator for the stream pointed to by stream. For a binary stream, the value is the number of characters from the beginning of the file. For a text stream, its file position indicator contains unspecified information, usable by the fseek function for returning the file position indicator for the stream to its position at the time of the ftell call; the difference between two such return values is not necessarily a meaningful measure of the number of characters written or read.

I think that’s the most important, but there are some more details.

Please help me convert this script to a simple image slider

Problems only surface when I am I trying to give the first loaded content an active state

Does this mean that you want to add a class to the first button?

$('.o-links').click(function(e) {   // ... }).first().addClass('O_Nav_Current'); 

instead of using IDs for the slider's items and resetting html contents you can use classes and indexes:

CSS:

.image-area {     width: 100%;     height: auto;     display: none; }  .image-area:first-of-type {     display: block; } 

JavaScript:

var $slides = $('.image-area'),     $btns = $('a.o-links');  $btns.on('click', function (e) {     var i = $btns.removeClass('O_Nav_Current').index(this);     $(this).addClass('O_Nav_Current');      $slides.filter(':visible').fadeOut(1000, function () {         $slides.eq(i).fadeIn(1000);     });      e.preventDefault();  }).first().addClass('O_Nav_Current'); 

http://jsfiddle.net/RmF57/

Highlight Anchor Links when user manually scrolls?

You can use Jquery's on method and listen for the scroll event.

Intermediate language used in scalac?

maybe this will help you out:

http://lampwww.epfl.ch/~paltherr/phd/altherr-phd.pdf

or this page:

www.scala-lang.org/node/6372‎

Are all Spring Framework Java Configuration injection examples buggy?

In your test, you are comparing the two TestParent beans, not the single TestedChild bean.

Also, Spring proxies your @Configuration class so that when you call one of the @Bean annotated methods, it caches the result and always returns the same object on future calls.

See here:

strange error in my Animation Drawable

Looks like whatever is in your Animation Drawable definition is too much memory to decode and sequence. The idea is that it loads up all the items and make them in an array and swaps them in and out of the scene according to the timing specified for each frame.

If this all can't fit into memory, it's probably better to either do this on your own with some sort of handler or better yet just encode a movie with the specified frames at the corresponding images and play the animation through a video codec.

Get Public URL for File - Google Cloud Storage - App Engine (Python)

You need to use get_serving_url from the Images API. As that page explains, you need to call create_gs_key() first to get the key to pass to the Images API.

Image steganography that could survive jpeg compression

Quite a few applications seem to implement Steganography on JPEG, so it's feasible:

http://www.jjtc.com/Steganography/toolmatrix.htm

Here's an article regarding a relevant algorithm (PM1) to get you started:

http://link.springer.com/article/10.1007%2Fs00500-008-0327-7#page-1

500 Error on AppHarbor but downloaded build works on my machine

Just a wild guess: (not much to go on) but I have had similar problems when, for example, I was using the IIS rewrite module on my local machine (and it worked fine), but when I uploaded to a host that did not have that add-on module installed, I would get a 500 error with very little to go on - sounds similar. It drove me crazy trying to find it.

So make sure whatever options/addons that you might have and be using locally in IIS are also installed on the host.

Similarly, make sure you understand everything that is being referenced/used in your web.config - that is likely the problem area.

Laravel 4 with Sentry 2 add user to a group on Registration

Somehow, where you are using Sentry, you're not using its Facade, but the class itself. When you call a class through a Facade you're not really using statics, it's just looks like you are.

Do you have this:

use Cartalyst\Sentry\Sentry; 

In your code?

Ok, but if this line is working for you:

$user = $this->sentry->register(array(     'username' => e($data['username']),     'email' => e($data['email']),      'password' => e($data['password'])     )); 

So you already have it instantiated and you can surely do:

$adminGroup = $this->sentry->findGroupById(5); 

Drag and drop menuitems

jQuery UI draggable and droppable are the two plugins I would use to achieve this effect. As for the insertion marker, I would investigate modifying the div (or container) element that was about to have content dropped into it. It should be possible to modify the border in some way or add a JavaScript/jQuery listener that listens for the hover (element about to be dropped) event and modifies the border or adds an image of the insertion marker in the right place.

php & mysql query not echoing in html with tags?

You need to append your variables to the echoed string. For example:

echo 'This is a string '.$PHPvariable.' and this is more string'; 

How do I show a message in the foreach loop?

You are looking to see if a single value is in an array. Use in_array.

However note that case is important, as are any leading or trailing spaces. Use var_dump to find out the length of the strings too, and see if they fit.

Target class controller does not exist - Laravel 8

Happened to me when I passing null to the middleware function

Route::middleware(null)->group(function () {
    Route::get('/some-path', [SomeController::class, 'search']);
});

Passing [] for no middleware works or probably just remove the middleware call if not using middleware :D

iPhone is not available. Please reconnect the device

I am not sure if covered in previous answers, but if you go to:

Xcode menu ? Window ? Devices and Simulators

You can see warnings and error messages for the device. For example, mine is below... I just updated everything, so I will need to workout where to go from here.

"The current device configuration is unsupported. This iPhone 11 is running iOS 13.6.1 (17G…"

"To run on this device, please update to a version of Xcode that supports iOS 13.6.1. You can download Xcode from the Mac App Store or the Apple Developer website."

DevTools failed to load SourceMap: Could not load content for chrome-extension

I do not think the warnings you have received are related. I had the same warnings which turned out to be the chrome extension React Dev Tools. Removed the extension and the errors have gone.

When adding a Javascript library, Chrome complains about a missing source map, why?

I get this warning in Angular if I run:

ng serve --sourceMap=false

To fix:

ng serve

SessionNotCreatedException: Message: session not created: This version of ChromeDriver only supports Chrome version 81

It is not python related but for C# or dotnet users you might specify driver version in nuget packages. For instance Selenium.WebDriver.ChromeDriver is a good start point. It should match browser version. In chrome you can check version by accessing

chrome://settings/help

Be informed that it will also affect chrome version on pipeline agents and other developer's computers.

Maven dependencies are failing with a 501 error

I was using a clean install of Maven/Java on a Docker container.

For me, I had to cd $M2_HOME/conf and edit the settings.xml file there. Add the following block inside <mirrors>...</mirrors>

<mirror>
  <id>central-secure</id>
  <url>https://repo.maven.apache.org/maven2</url>
  <mirrorOf>central</mirrorOf>
</mirror>

IntelliJ: Error:java: error: release version 5 not supported

By default, your "Project bytecode version isn't set in maven project.

It thinks that your current version is 5.

Solution 1:

Just go to "Project Settings>Build, Execution...>compiler>java compiler" and then change your bytecode version to your current java version.

Solution 2:

Adding below build plugin in POM file:

 <properties>
        <java.version>1.8</java.version>
        <maven.compiler.version>3.8.1</maven.compiler.version>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>${maven.compiler.version}</version>
                <configuration>
                    <source>${java.version}</source>
                    <target>${java.version}</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

Message: Trying to access array offset on value of type null

This happens because $cOTLdata is not null but the index 'char_data' does not exist. Previous versions of PHP may have been less strict on such mistakes and silently swallowed the error / notice while 7.4 does not do this anymore.

To check whether the index exists or not you can use isset():

isset($cOTLdata['char_data'])

Which means the line should look something like this:

$len = isset($cOTLdata['char_data']) ? count($cOTLdata['char_data']) : 0;

Note I switched the then and else cases of the ternary operator since === null is essentially what isset already does (but in the positive case).

Template not provided using create-react-app

If you are getting this error 'Template not provided ...." again and again, then straigt away do the followiong to steps:

  1. npm uninstall -g create-react-app
  2. check the location of your file 'create-react-app' by using the command "which create-react-app"
  3. Now manually delete that file using the command "rm -rf /usr/local/bin/create-react-app" replacing this command with the exact path shown in the previous step.
  4. Finally run 'npx create-react-app '

This will replace your old file 'create-react-app' which is causing the problem with the new file downloaded with npx.

Happy coding...

Visual Studio Code PHP Intelephense Keep Showing Not Necessary Error

In my case, for some reason, vendor folder was disabled on VS Code settings:

    "intelephense.files.exclude": [
        "**/.git/**",
        "**/.svn/**",
        "**/.hg/**",
        "**/CVS/**",
        "**/.DS_Store/**",
        "**/node_modules/**",
        "**/bower_components/**",
        "**/vendor/**", <-- remove this line!
        "**/resources/views/**"
    ],

By removing the line containing vendor folder it works ok on version Intelephense 1.5.4

Upgrade to python 3.8 using conda

Open Anaconda Prompt (base):

  1. Update conda:
conda update -n base -c defaults conda
  1. Create new environment with Python 3.8:
conda create -n python38 python=3.8
  1. Activate your new Python 3.8 environment:
conda activate python38
  1. Start Python 3.8:
python

SameSite warning Chrome 77

If you are testing on localhost and you have no control of the response headers, you can disable it with a chrome flag.

Visit the url and disable it: chrome://flags/#same-site-by-default-cookies SameSite by default cookies screenshot

I need to disable it because Chrome Canary just started enforcing this rule as of approximately V 82.0.4078.2 and now it's not setting these cookies.

Note: I only turn this flag on in Chrome Canary that I use for development. It's best not to turn the flag on for everyday Chrome browsing for the same reasons that google is introducing it.

What's the net::ERR_HTTP2_PROTOCOL_ERROR about?

I have been experiencing this problem for the last week now as I've been trying to send DELETE requests to my PHP server through AJAX. I recently upgraded my hosting plan where I now have an SSL Certificate on my host which stores the PHP and JS files. Since adding an SSL Certificate I no longer experience this issue. Hoping this helps with this strange error.

"Uncaught SyntaxError: Cannot use import statement outside a module" when importing ECMAScript 6

I resolved my case by replacing "import" by "require".

// import { parse } from 'node-html-parser';
parse = require('node-html-parser');

How to fix "set SameSite cookie to none" warning?

I am using both JavaScript Cookie and Java CookieUtil in my project, below settings solved my problem:

JavaScript Cookie

var d = new Date();
d.setTime(d.getTime() + (30*24*60*60*1000)); //keep cookie 30 days
var expires = "expires=" + d.toGMTString();         
document.cookie = "visitName" + "=Hailin;" + expires + ";path=/;SameSite=None;Secure"; //can set SameSite=Lax also

JAVA Cookie (set proxy_cookie_path in Nginx)

location / {
   proxy_pass http://96.xx.xx.34;
   proxy_intercept_errors on;
   #can set SameSite=None also
   proxy_cookie_path / "/;SameSite=Lax;secure";
   proxy_connect_timeout 600;
   proxy_read_timeout 600;
}

Check result in Firefox enter image description here

Read more on https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie/SameSite

How to prevent Google Colab from disconnecting?

For me the following examples:

  • document.querySelector("#connect").click() or
  • document.querySelector("colab-toolbar-button#connect").click() or
  • document.querySelector("colab-connect-button").click()

were throwing errors.

I had to adapt them to the following:

Version 1:

function ClickConnect(){
  console.log("Connnect Clicked - Start"); 
  document.querySelector("#top-toolbar > colab-connect-button").shadowRoot.querySelector("#connect").click();
  console.log("Connnect Clicked - End"); 
};
setInterval(ClickConnect, 60000)

Version 2: If you would like to be able to stop the function, here is the new code:

var startClickConnect = function startClickConnect(){
    var clickConnect = function clickConnect(){
        console.log("Connnect Clicked - Start");
        document.querySelector("#top-toolbar > colab-connect-button").shadowRoot.querySelector("#connect").click();
        console.log("Connnect Clicked - End"); 
    };

    var intervalId = setInterval(clickConnect, 60000);

    var stopClickConnectHandler = function stopClickConnect() {
        console.log("Connnect Clicked Stopped - Start");
        clearInterval(intervalId);
        console.log("Connnect Clicked Stopped - End");
    };

    return stopClickConnectHandler;
};

var stopClickConnect = startClickConnect();

In order to stop, call:

stopClickConnect();

Element implicitly has an 'any' type because expression of type 'string' can't be used to index

I use this:

interface IObjectKeys {
  [key: string]: string | number;
}

interface IDevice extends IObjectKeys {
  id: number;
  room_id: number;
  name: string;
  type: string;
  description: string;
}

If you use the optional property in your object:

interface IDevice extends IObjectKeys {
  id: number;
  room_id?: number;
  name?: string;
  type?: string;
  description?: string;
}

... you should add 'undefined' value into the IObjectKeys interface:

interface IObjectKeys {
  [key: string]: string | number | undefined;
}

dotnet ef not found in .NET Core 3

I was having this problem after I installed the dotnet-ef tool using Ansible with sudo escalated previllage on Ubuntu. I had to add become: no for the Playbook task, then the dotnet-ef tool became available to the current user.

  - name: install dotnet tool dotnet-ef
    command: dotnet tool install --global dotnet-ef --version {{dotnetef_version}}
    become: no

Make a VStack fill the width of the screen in SwiftUI

An alternative stacking arrangement which works and is perhaps a bit more intuitive is the following:

struct ContentView: View {
    var body: some View {
        HStack() {
            VStack(alignment: .leading) {
                Text("Hello World")
                    .font(.title)
                Text("Another")
                    .font(.body)
                Spacer()
            }
            Spacer()
        }.background(Color.red)
    }
}

The content can also easily be re-positioned by removing the Spacer()'s if necessary.

adding/removing Spacers to change position

Access blocked by CORS policy: Response to preflight request doesn't pass access control check

You can just create the required CORS configuration as a bean. As per the code below this will allow all requests coming from any origin. This is good for development but insecure. Spring Docs

@Bean
WebMvcConfigurer corsConfigurer() {
    return new WebMvcConfigurer() {
        @Override
        void addCorsMappings(CorsRegistry registry) {
            registry.addMapping("/**")
                    .allowedOrigins("*")
        }
    }
}

Presenting modal in iOS 13 fullscreen

Here's my version of fix in ObjectiveC using Categories. With this approach you'll have default UIModalPresentationStyleFullScreen behaviour until another one explicitly set.

#import "UIViewController+Presentation.h"
#import "objc/runtime.h"

@implementation UIViewController (Presentation)

- (void)setModalPresentationStyle:(UIModalPresentationStyle)modalPresentationStyle {
    [self setPrivateModalPresentationStyle:modalPresentationStyle];
}

-(UIModalPresentationStyle)modalPresentationStyle {
    UIModalPresentationStyle style = [self privateModalPresentationStyle];
    if (style == NSNotFound) {
        return UIModalPresentationFullScreen;
    }
    return style;
}

- (void)setPrivateModalPresentationStyle:(UIModalPresentationStyle)modalPresentationStyle {
    NSNumber *styleNumber = [NSNumber numberWithInteger:modalPresentationStyle];
     objc_setAssociatedObject(self, @selector(privateModalPresentationStyle), styleNumber, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (UIModalPresentationStyle)privateModalPresentationStyle {
    NSNumber *styleNumber = objc_getAssociatedObject(self, @selector(privateModalPresentationStyle));
    if (styleNumber == nil) {
        return NSNotFound;
    }
    return styleNumber.integerValue;
}

@end

origin 'http://localhost:4200' has been blocked by CORS policy in Angular7

You are all good at Angular side even postman not raise the cors policy issue. This type of issue is solved at back-end side in major cases.

If you are using Spring boot the you can avoid this issue by placing this annotation at your controller class or at any particular method.

@CrossOrigin(origins = "http://localhost:4200")

In case of global configuration with spring boot configure following two class:

`

@EnableWebSecurity
@AllArgsConstructor

public class SecurityConfig extends WebSecurityConfigurerAdapter {
@Override
    public void configure(HttpSecurity httpSecurity) throws Exception{
        httpSecurity.csrf().disable()
        .authorizeRequests()
        .antMatchers("/api1/**").permitAll()
        .antMatchers("/api2/**").permitAll()
        .antMatchers("/api3/**").permitAll()
        
}
`

@Configuration
@EnableWebMvc
public class WebConfig implements WebMvcConfigurer {

    @Override
    public void addCorsMappings(CorsRegistry corsRegistry) {
        corsRegistry.addMapping("/**")
                .allowedOrigins("http://localhost:4200")
                .allowedMethods("*")
                .maxAge(3600L)
                .allowedHeaders("*")
                .exposedHeaders("Authorization")
                .allowCredentials(true);
    }

Why am I getting Unknown error in line 1 of pom.xml?

In my pom.xml file I had to downgrade the version from 2.1.6.RELEASE for spring-boot-starter-parent artifact to 2.1.4.RELEASE

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.6.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
</parent>

to be changed to

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.4.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
</parent>

And that weird Unknown error disappeared

What is the incentive for curl to release the library for free?

I'm Daniel Stenberg.

I made curl

I founded the curl project back in 1998, I wrote the initial curl version and I created libcurl. I've written more than half of all the 24,000 commits done in the source code repository up to this point in time. I'm still the lead developer of the project. To a large extent, curl is my baby.

I shipped the first version of curl as open source since I wanted to "give back" to the open source world that had given me so much code already. I had used so much open source and I wanted to be as cool as the other open source authors.

Thanks to it being open source, literally thousands of people have been able to help us out over the years and have improved the products, the documentation. the web site and just about every other detail around the project. curl and libcurl would never have become the products that they are today were they not open source. The list of contributors now surpass 1900 names and currently the list grows with a few hundred names per year.

Thanks to curl and libcurl being open source and liberally licensed, they were immediately adopted in numerous products and soon shipped by operating systems and Linux distributions everywhere thus getting a reach beyond imagination.

Thanks to them being "everywhere", available and liberally licensed they got adopted and used everywhere and by everyone. It created a defacto transfer library standard.

At an estimated six billion installations world wide, we can safely say that curl is the most widely used internet transfer library in the world. It simply would not have gone there had it not been open source. curl runs in billions of mobile phones, a billion Windows 10 installations, in a half a billion games and several hundred million TVs - and more.

Should I have released it with proprietary license instead and charged users for it? It never occured to me, and it wouldn't have worked because I would never had managed to create this kind of stellar project on my own. And projects and companies wouldn't have used it.

Why do I still work on curl?

Now, why do I and my fellow curl developers still continue to develop curl and give it away for free to the world?

  1. I can't speak for my fellow project team members. We all participate in this for our own reasons.
  2. I think it's still the right thing to do. I'm proud of what we've accomplished and I truly want to make the world a better place and I think curl does its little part in this.
  3. There are still bugs to fix and features to add!
  4. curl is free but my time is not. I still have a job and someone still has to pay someone for me to get paid every month so that I can put food on the table for my family. I charge customers and companies to help them with curl. You too can get my help for a fee, which then indirectly helps making sure that curl continues to evolve, remain free and the kick-ass product it is.
  5. curl was my spare time project for twenty years before I started working with it full time. I've had great jobs and worked on awesome projects. I've been in a position of luxury where I could continue to work on curl on my spare time and keep shipping a quality product for free. My work on curl has given me friends, boosted my career and taken me to places I would not have been at otherwise.
  6. I would not do it differently if I could back and do it again.

Am I proud of what we've done?

Yes. So insanely much.

But I'm not satisfied with this and I'm not just leaning back, happy with what we've done. I keep working on curl every single day, to improve, to fix bugs, to add features and to make sure curl keeps being the number one file transfer solution for the world even going forward.

We do mistakes along the way. We make the wrong decisions and sometimes we implement things in crazy ways. But to win in the end and to conquer the world is about patience and endurance and constantly going back and reconsidering previous decisions and correcting previous mistakes. To continuously iterate, polish off rough edges and gradually improve over time.

Never give in. Never stop. Fix bugs. Add features. Iterate. To the end of time.

For real?

Yeah. For real.

Do I ever get tired? Is it ever done?

Sure I get tired at times. Working on something every day for over twenty years isn't a paved downhill road. Sometimes there are obstacles. During times things are rough. Occasionally people are just as ugly and annoying as people can be.

But curl is my life's project and I have patience. I have thick skin and I don't give up easily. The tough times pass and most days are awesome. I get to hang out with awesome people and the reward is knowing that my code helps driving the Internet revolution everywhere is an ego boost above normal.

curl will never be "done" and so far I think work on curl is pretty much the most fun I can imagine. Yes, I still think so even after twenty years in the driver's seat. And as long as I think it's fun I intend to keep at it.

Module 'tensorflow' has no attribute 'contrib'

I used tensorflow 1.8 to train my model and there is no problem for now. Tensorflow 2.0 alpha is not suitable with object detection API

How to fix missing dependency warning when using useEffect React Hook?

The solution is also given by react, they advice you use useCallback which will return a memoize version of your function :

The 'fetchBusinesses' function makes the dependencies of useEffect Hook (at line NN) change on every render. To fix this, wrap the 'fetchBusinesses' definition into its own useCallback() Hook react-hooks/exhaustive-deps

useCallback is simple to use as it has the same signature as useEffect the difference is that useCallback returns a function. It would look like this :

 const fetchBusinesses = useCallback( () => {
        return fetch("theURL", {method: "GET"}
    )
    .then(() => { /* some stuff */ })
    .catch(() => { /* some error handling */ })
  }, [/* deps */])
  // We have a first effect thant uses fetchBusinesses
  useEffect(() => {
    // do things and then fetchBusinesses
    fetchBusinesses(); 
  }, [fetchBusinesses]);
   // We can have many effect thant uses fetchBusinesses
  useEffect(() => {
    // do other things and then fetchBusinesses
    fetchBusinesses();
  }, [fetchBusinesses]);

React Native Error: ENOSPC: System limit for number of file watchers reached

I had the same problem by using library wifi but when i changed my network it worked perfectly.

Change your network connection

Is it possible to install Xcode 10.2 on High Sierra (10.13.6)?

Cracked it. Just @Damnum steps and then follow the path to run xcode. Bad way but running like a charm.

Double click to /Applications/Xcode102.app/Contents/MacOS/Xcode

Unable to load script.Make sure you are either running a Metro server or that your bundle 'index.android.bundle' is packaged correctly for release

This worked for me after trying several ways.

In the file node_modules\metro-config\src\defaults\blacklist.js

Replace :

var sharedBlacklist = [
  /node_modules[/\\]react[/\\]dist[/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

with :

var sharedBlacklist = [
  /node_modules[\/\\]react[\/\\]dist[\/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

hope this helps.

Module not found: Error: Can't resolve 'core-js/es6'

The imports have changed for core-js version 3.0.1 - for example

import 'core-js/es6/array'; and import 'core-js/es7/array';

can now be provided simply by the following

import 'core-js/es/array';

if you would prefer not to bring in the whole of core-js

Browserslist: caniuse-lite is outdated. Please run next command `npm update caniuse-lite browserslist`

I'm not exactly sure where my problem was, but I believe it was because I was using the same global packages from both npm and Yarn.

I uninstalled all the npm global packages, then when using yarn commands once again, the problem was gone.

To see global packages installed...

for npm:

npm ls -g --depth=0

for Yarn:

yarn global list

I then uninstalled each package I saw in the npm listing, using:

npm uninstall -g <package-name>

session not created: This version of ChromeDriver only supports Chrome version 74 error with ChromeDriver Chrome using Selenium

I have almost the same problems like this, the problems is come inside the pipeline when running my selenium test that need chromedriver package to running the e2e test.

My error build pipeline

The problems is just because in the pipeline (in my case) is having the chrome version 73, and my chromedriver package is installed on version 74.

Finally there are two simple solutions:

  1. Downgrade your chrome
  2. Downgrade your chromedriver package version. in my case, cause i running inside the pipeline i need to install chromedriver before running the selenium test like displayed below.

    - script: npm install [email protected] --chromedriver-force-download displayName: 'Install Chrome'

The POST method is not supported for this route. Supported methods: GET, HEAD. Laravel

There are multiple ways you can handle this:

  1. If you insist on using PUT you can change the form action to POST and add a hidden method_field that has a value PUTand a hidden csrf field (if you are using blade then you just need to add @csrf_field and {{ method_field('PUT') }}). This way the form would accept the request.

  2. You can simply change the route and form method to POST. It will work just fine since you are the one defining the route and not using the resource group.

react hooks useEffect() cleanup for only componentWillUnmount?

you can use more than one useEffect

for example if my variable is data1 i can use all of this in my component

useEffect( () => console.log("mount"), [] );
useEffect( () => console.log("will update data1"), [ data1 ] );
useEffect( () => console.log("will update any") );
useEffect( () => () => console.log("will update data1 or unmount"), [ data1 ] );
useEffect( () => () => console.log("unmount"), [] );

Why am I seeing net::ERR_CLEARTEXT_NOT_PERMITTED errors after upgrading to Cordova Android 8?

After a few days of struggle, this works for me, and I hope this also works for you.

add this to your CONFIG.XML, top of your code.

<access origin="*" />
<allow-navigation href="*" />

and this, under the platform android.

<edit-config file="app/src/main/AndroidManifest.xml" 
   mode="merge" target="/manifest/application" 
   xmlns:android="http://schemas.android.com/apk/res/android">
     <application android:usesCleartextTraffic="true" />
     <application android:networkSecurityConfig="@xml/network_security_config" />
 </edit-config>
 <resource-file src="resources/android/xml/network_security_config.xml" 
 target="app/src/main/res/xml/network_security_config.xml" />

add the follow code to this file "resources/android/xml/network_security_config.xml".

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <base-config cleartextTrafficPermitted="true">
        <trust-anchors>
            <certificates src="system" />
        </trust-anchors>
    </base-config>
    <domain-config cleartextTrafficPermitted="true">
        <domain includeSubdomains="true">localhost</domain>
        <domain includeSubdomains="true">YOUR DOMAIN HERE/IP</domain>
    </domain-config>
</network-security-config>

enter image description here

enter image description here

The iOS Simulator deployment targets is set to 7.0, but the range of supported deployment target version for this platform is 8.0 to 12.1

The problem is in your pod files deployment target iOS Version not in your project deployment target iOS Version, so you need to change the deployment iOS version for your pods as well to anything higher than 8.0 to do so open your project workspace and do this:

1- Click on pods.

2- Select each project and target and click on build settings.

3- Under Deployment section change the iOS Deployment Target version to anything more than 8.0 (better to try the same project version).

4- Repeat this for every other project in your pods then run the app.

see the photo for details enter image description here

How to Install pip for python 3.7 on Ubuntu 18?

For those who intend to use venv:

If you don't already have pip for Python 3:

sudo apt install python3-pip

Install venv package:

sudo apt install python3.7-venv

Create virtual environment (which will be bootstrapped with pip by default):

python3.7 -m venv /path/to/new/virtual/environment

To activate the virtual environment, source the appropriate script for the current shell, from the bin directory of the virtual environment. The appropriate scripts for the different shells are:

bash/zsh – activate

fish – activate.fish

csh/tcsh – activate.csh

For example, if using bash:

source /path/to/new/virtual/environment/bin/activate

Optionally, to update pip for the virtual environment (while it is activated):

pip install --upgrade pip

When you want to deactivate the virtual environment:

deactivate 

JS file gets a net::ERR_ABORTED 404 (Not Found)

As mentionned in comments: you need a way to send your static files to the client. This can be achieved with a reverse proxy like Nginx, or simply using express.static().

Put all your "static" (css, js, images) files in a folder dedicated to it, different from where you put your "views" (html files in your case). I'll call it static for the example. Once it's done, add this line in your server code:

app.use("/static", express.static('./static/'));

This will effectively serve every file in your "static" folder via the /static route.

Querying your index.js file in the client thus becomes:

<script src="static/index.js"></script>

Error: Java: invalid target release: 11 - IntelliJ IDEA

i also got same error , i just change the java version in pom.xml from 11 to 1.8 and it's work fine.

How to setup virtual environment for Python in VS Code?

With a newer VS Code version it's quite simple.

Open VS Code in your project's folder.

Then open Python Terminal (Ctrl-Shift-P: Python: Create Terminal)

In the terminal:

python -m venv .venv

you'll then see the following dialog: enter image description here

click Yes

Then Python: Select Interpreter (via Ctrl-Shift-P)

and select the option (in my case towards the bottom)

Python 3.7 (venv) ./venv/Scripts/python.exe

If you see

Activate.ps1 is not digitally signed. You cannot run this script on the current system.

you'll need to do the following: https://stackoverflow.com/a/18713789/2705777

For more information see: https://code.visualstudio.com/docs/python/environments#_global-virtual-and-conda-environments

Git fatal: protocol 'https' is not supported

You tried this:

clt + V

Just right click and click on paste

Hope this will work

Can't perform a React state update on an unmounted component

I had a similar problem and solved it :

I was automatically making the user logged-in by dispatching an action on redux ( placing authentication token on redux state )

and then I was trying to show a message with this.setState({succ_message: "...") in my component.

Component was looking empty with the same error on console : "unmounted component".."memory leak" etc.

After I read Walter's answer up in this thread

I've noticed that in the Routing table of my application , my component's route wasn't valid if user is logged-in :

{!this.props.user.token &&
        <div>
            <Route path="/register/:type" exact component={MyComp} />                                             
        </div>
}

I made the Route visible whether the token exists or not.

Pylint "unresolved import" error in Visual Studio Code

In my case I already had a Conda environment activated, but I still wanted local Python modules to be available for autocomplete, peeking definition, etc.

I tried many solutions such as adding a list of Python paths etc., but what finally solved it for me was to create a symbolic link from Conda's lib/python{your version}/site-packages to my local module.

How to make an AlertDialog in Flutter?

One Button

showAlertDialog(BuildContext context) {

  // set up the button
  Widget okButton = FlatButton(
    child: Text("OK"),
    onPressed: () { },
  );

  // set up the AlertDialog
  AlertDialog alert = AlertDialog(
    title: Text("My title"),
    content: Text("This is my message."),
    actions: [
      okButton,
    ],
  );

  // show the dialog
  showDialog(
    context: context,
    builder: (BuildContext context) {
      return alert;
    },
  );
}

Two Buttons

showAlertDialog(BuildContext context) {

  // set up the buttons
  Widget cancelButton = FlatButton(
    child: Text("Cancel"),
    onPressed:  () {},
  );
  Widget continueButton = FlatButton(
    child: Text("Continue"),
    onPressed:  () {},
  );

  // set up the AlertDialog
  AlertDialog alert = AlertDialog(
    title: Text("AlertDialog"),
    content: Text("Would you like to continue learning how to use Flutter alerts?"),
    actions: [
      cancelButton,
      continueButton,
    ],
  );

  // show the dialog
  showDialog(
    context: context,
    builder: (BuildContext context) {
      return alert;
    },
  );
}

Three Buttons

showAlertDialog(BuildContext context) {

  // set up the buttons
  Widget remindButton = FlatButton(
    child: Text("Remind me later"),
    onPressed:  () {},
  );
  Widget cancelButton = FlatButton(
    child: Text("Cancel"),
    onPressed:  () {},
  );
  Widget launchButton = FlatButton(
    child: Text("Launch missile"),
    onPressed:  () {},
  );

  // set up the AlertDialog
  AlertDialog alert = AlertDialog(
    title: Text("Notice"),
    content: Text("Launching this missile will destroy the entire universe. Is this what you intended to do?"),
    actions: [
      remindButton,
      cancelButton,
      launchButton,
    ],
  );

  // show the dialog
  showDialog(
    context: context,
    builder: (BuildContext context) {
      return alert;
    },
  );
}

Handling button presses

The onPressed callback for the buttons in the examples above were empty, but you could add something like this:

Widget launchButton = FlatButton(
  child: Text("Launch missile"),
  onPressed:  () {
    Navigator.of(context).pop(); // dismiss dialog
    launchMissile();
  },
);

If you make the callback null, then the button will be disabled.

onPressed: null,

enter image description here

Supplemental code

Here is the code for main.dart in case you weren't getting the functions above to run.

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter',
      home: Scaffold(
        appBar: AppBar(
          title: Text('Flutter'),
        ),
        body: MyLayout()),
    );
  }
}

class MyLayout extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.all(8.0),
      child: RaisedButton(
        child: Text('Show alert'),
        onPressed: () {
          showAlertDialog(context);
        },
      ),
    );
  }
}

// replace this function with the examples above
showAlertDialog(BuildContext context) { ... }

"Repository does not have a release file" error

I have been having this issue for a couple of weeks and finally decided to sit down and try and fix it. I have no interest in config file editing as I'm primarily a Windows user.

In a fit of "clickyness" I noticed that the ubuntu server location was set "for United kingdom". I switched this over to "Main Server" and hey presto... it all stared updating.

So, it seems like the regionalised server (for the UK at least) has a very limited support window so if you are an infrequent user it is likely it will not have a valid upgrade path from your current version to the latest.

Edit: I only just noticted the previous reply, after posting. 100% agree.

Android Gradle 5.0 Update:Cause: org.jetbrains.plugins.gradle.tooling.util

I have the same problem after upgrading to Gradle Wrapper 5.0., Now I switch back to 4.10.3 which just released 5 December 2018 based on Gradle documentation and use Android Gradle Plugin: 3.2.1 (the latest stable version).

Pandas Merging 101

In this answer, I will consider practical examples.

The first one, is of pandas.concat.

The second one, of merging dataframes from the index of one and the column of another one.


1. pandas.concat

Considering the following DataFrames with the same column names:

Preco2018 with size (8784, 5)

DataFrame 1

Preco 2019 with size (8760, 5)

DataFrame 2

That have the same column names.

You can combine them using pandas.concat, by simply

import pandas as pd

frames = [Preco2018, Preco2019]

df_merged = pd.concat(frames)

Which results in a DataFrame with the following size (17544, 5)

DataFrame result of the combination of two dataframes

If you want to visualize, it ends up working like this

How concat works

(Source)


2. Merge by Column and Index

In this part, I will consider a specific case: If one wants to merge the index of one dataframe and the column of another dataframe.

Let's say one has the dataframe Geo with 54 columns, being one of the columns the Date Data, which is of type datetime64[ns].

enter image description here

And the dataframe Price that has one column with the price and the index corresponds to the dates

enter image description here

In this specific case, to merge them, one uses pd.merge

merged = pd.merge(Price, Geo, left_index=True, right_on='Data')

Which results in the following dataframe

enter image description here

What does double question mark (??) operator mean in PHP

$x = $y ?? 'dev'

is short hand for x = y if y is set, otherwise x = 'dev'

There is also

$x = $y =="SOMETHING" ? 10 : 20

meaning if y equals 'SOMETHING' then x = 10, otherwise x = 20

Numpy, multiply array with scalar

You can multiply numpy arrays by scalars and it just works.

>>> import numpy as np
>>> np.array([1, 2, 3]) * 2
array([2, 4, 6])
>>> np.array([[1, 2, 3], [4, 5, 6]]) * 2
array([[ 2,  4,  6],
       [ 8, 10, 12]])

This is also a very fast and efficient operation. With your example:

>>> a_1 = np.array([1.0, 2.0, 3.0])
>>> a_2 = np.array([[1., 2.], [3., 4.]])
>>> b = 2.0
>>> a_1 * b
array([2., 4., 6.])
>>> a_2 * b
array([[2., 4.],
       [6., 8.]])

How to compare oldValues and newValues on React Hooks useEffect?

Here's a custom hook that I use which I believe is more intuitive than using usePrevious.

import { useRef, useEffect } from 'react'

// useTransition :: Array a => (a -> Void, a) -> Void
//                              |_______|  |
//                                  |      |
//                              callback  deps
//
// The useTransition hook is similar to the useEffect hook. It requires
// a callback function and an array of dependencies. Unlike the useEffect
// hook, the callback function is only called when the dependencies change.
// Hence, it's not called when the component mounts because there is no change
// in the dependencies. The callback function is supplied the previous array of
// dependencies which it can use to perform transition-based effects.
const useTransition = (callback, deps) => {
  const func = useRef(null)

  useEffect(() => {
    func.current = callback
  }, [callback])

  const args = useRef(null)

  useEffect(() => {
    if (args.current !== null) func.current(...args.current)
    args.current = deps
  }, deps)
}

You'd use useTransition as follows.

useTransition((prevRate, prevSendAmount, prevReceiveAmount) => {
  if (sendAmount !== prevSendAmount || rate !== prevRate && sendAmount > 0) {
    const newReceiveAmount = sendAmount * rate
    // do something
  } else {
    const newSendAmount = receiveAmount / rate
    // do something
  }
}, [rate, sendAmount, receiveAmount])

Hope that helps.

React Hook Warnings for async function in useEffect: useEffect function must return a cleanup function or nothing

try

_x000D_
_x000D_
const MyFunctionnalComponent: React.FC = props => {_x000D_
  useEffect(() => {_x000D_
    // Using an IIFE_x000D_
    (async function anyNameFunction() {_x000D_
      await loadContent();_x000D_
    })();_x000D_
  }, []);_x000D_
  return <div></div>;_x000D_
};
_x000D_
_x000D_
_x000D_

FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory in ionic 3

Pls check your node version :

_x000D_
_x000D_
   $  node -v
_x000D_
_x000D_
_x000D_

If its 10.1.1 something , then you need to update your root level node version via below commands

_x000D_
_x000D_
$ curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.3/install.sh | bash


$ source ~/.nvm/nvm.sh

$ nvm ls

$ nvm install 12.18.1
_x000D_
_x000D_
_x000D_

Once done pls restart your terminal or visual studio.

It's work 100$

For ionic user pls add the below code in your package.json for ionic user

_x000D_
_x000D_
 "ionic:build": "node --max-old-space-size=16384 ./node_modules/@ionic/app-scripts/bin/ionic-app-scripts.js build",
    
_x000D_
_x000D_
_x000D_

Set the space between Elements in Row Flutter

Just add "Container(width: 5, color: Colors.transparent)," between elements

new Container(
      alignment: FractionalOffset.center,
      child: new Row(
        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
        children: <Widget>[
          new FlatButton(
            child: new Text('Don\'t have an account?', style: new TextStyle(color: Color(0xFF2E3233))),
          ),
            Container(width: 5, color: Colors.transparent),
          new FlatButton(
            child: new Text('Register.', style: new TextStyle(color: Color(0xFF84A2AF), fontWeight: FontWeight.bold),),
            onPressed: moveToRegister,
          )
        ],
      ),
    ),  

A fatal error occurred while creating a TLS client credential. The internal error state is 10013

Basically we had to enable TLS 1.2 for .NET 4.x. Making this registry changed worked for me, and stopped the event log filling up with the Schannel error.

More information on the answer can be found here

Linked Info Summary

Enable TLS 1.2 at the system (SCHANNEL) level:

Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2]
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client]
"DisabledByDefault"=dword:00000000
"Enabled"=dword:00000001
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server]
"DisabledByDefault"=dword:00000000
"Enabled"=dword:00000001

(equivalent keys are probably also available for other TLS versions)

Tell .NET Framework to use the system TLS versions:

Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319]
"SystemDefaultTlsVersions"=dword:00000001
[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\.NETFramework\v4.0.30319]
"SystemDefaultTlsVersions"=dword:00000001

This may not be desirable for edge cases where .NET Framework 4.x applications need to have different protocols enabled and disabled than the OS does.

How to call loading function with React useEffect only once

leave the dependency array blank . hope this will help you understand better.

   useEffect(() => {
      doSomething()
    }, []) 

empty dependency array runs Only Once, on Mount

useEffect(() => {
  doSomething(value)
}, [value])  

pass value as a dependency. if dependencies has changed since the last time, the effect will run again.

useEffect(() => {
  doSomething(value)
})  

no dependency. This gets called after every render.

Angular CLI Error: The serve command requires to be run in an Angular project, but a project definition could not be found

This happens when you try to run the Angular command "ng s" or "ng serve" on the other folder instead of the root folder of the Angular application.

Also upgrade the Angular using the following command:

ng update @angular/cli --migrate-only --from=1.7.4

This will sort it out.

How to set width of mat-table column in angular?

we can add attribute width directly to th

eg:

<ng-container matColumnDef="position" >
    <th mat-header-cell *matHeaderCellDef width ="20%"> No. </th>
    <td mat-cell *matCellDef="let element"> {{element.position}} </td>
  </ng-container>

Flutter: RenderBox was not laid out

I had a similir problem, but in my case, I put a row in the leading of the ListView, and it was consuming all the space, of course. I just had to take the Row out of the leading, and it was solved. I would recommend to check if the problem is a larger widget than its container can have.

Expanded(child:MyListView())

WebView showing ERR_CLEARTEXT_NOT_PERMITTED although site is HTTPS

Solution:

Add the below line in your application tag:

android:usesCleartextTraffic="true"

As shown below:

<application
    ....
    android:usesCleartextTraffic="true"
    ....>

UPDATE: If you have network security config such as: android:networkSecurityConfig="@xml/network_security_config"

No Need to set clear text traffic to true as shown above, instead use the below code:

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
    <domain-config cleartextTrafficPermitted="true">
        ....
        ....
    </domain-config>

    <base-config cleartextTrafficPermitted="false"/>
</network-security-config>  

Set the cleartextTrafficPermitted to true

Hope it helps.

How do I install Java on Mac OSX allowing version switching?

You can use asdf to install and switch between multiple java versions. It has plugins for other languages as well. You can install asdf with Homebrew

brew install asdf

When asdf is configured, install java plugin

asdf plugin-add java

Pick a version to install

asdf list-all java

For example to install and configure adoptopenjdk8

asdf install java adoptopenjdk-8.0.272+10
asdf global java adoptopenjdk-8.0.272+10

And finally if needed, configure JAVA_HOME for your shell. Just add to your shell init script such as ~/.zshrc in case of zsh:

. ~/.asdf/plugins/java/set-java-home.zsh

How to install OpenJDK 11 on Windows?

AdoptOpenJDK is a new website hosted by the java community. You can find .msi installers for OpenJDK 8 through 14 there, which will perform all the things listed in the question (Unpacking, registry keys, PATH variable updating (and JAVA_HOME), uninstaller...).

How to install JDK 11 under Ubuntu?

To install Openjdk 11 in Ubuntu, the following commands worked well.

sudo add-apt-repository ppa:openjdk-r/ppa
sudo apt-get update
sudo apt install openjdk-11-jdk

Java 11 package javax.xml.bind does not exist

According to the release-notes, Java 11 removed the Java EE modules:

java.xml.bind (JAXB) - REMOVED
  • Java 8 - OK
  • Java 9 - DEPRECATED
  • Java 10 - DEPRECATED
  • Java 11 - REMOVED

See JEP 320 for more info.

You can fix the issue by using alternate versions of the Java EE technologies. Simply add Maven dependencies that contain the classes you need:

<dependency>
  <groupId>javax.xml.bind</groupId>
  <artifactId>jaxb-api</artifactId>
  <version>2.3.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-core</artifactId>
  <version>2.3.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>2.3.0</version>
</dependency>

Jakarta EE 8 update (Mar 2020)

Instead of using old JAXB modules you can fix the issue by using Jakarta XML Binding from Jakarta EE 8:

<dependency>
  <groupId>jakarta.xml.bind</groupId>
  <artifactId>jakarta.xml.bind-api</artifactId>
  <version>2.3.3</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>2.3.3</version>
  <scope>runtime</scope>
</dependency>

Jakarta EE 9 update (Nov 2020)

Use latest release of Eclipse Implementation of JAXB 3.0.0:

<dependency>
  <groupId>jakarta.xml.bind</groupId>
  <artifactId>jakarta.xml.bind-api</artifactId>
  <version>3.0.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>3.0.0</version>
  <scope>runtime</scope>
</dependency>

Note: Jakarta EE 9 adopts new API package namespace jakarta.xml.bind.*, so update import statements:

javax.xml.bind -> jakarta.xml.bind

How to change status bar color in Flutter?

to Make it Like your App Bar Color

import 'package:flutter/material.dart';

 Widget build(BuildContext context) {
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(
      statusBarColor: Colors.transparent,
      systemNavigationBarColor: Colors.transparent,
  ));
 }

WARNING: API 'variant.getJavaCompile()' is obsolete and has been replaced with 'variant.getJavaCompileProvider()'

When the plugin detects that you're using an API that's no longer supported, it can now provide more-detailed information to help you determine where that API is being used. To see the additional info, you need to include the following in your project's gradle.properties file:

android.debug.obsoleteApi=true

IntelliJ can't recognize JavaFX 11 with OpenJDK 11

The issue that JavaFX is no longer part of JDK 11. The following solution works using IntelliJ (haven't tried it with NetBeans):

  1. Add JavaFX Global Library as a dependency:

    Settings -> Project Structure -> Module. In module go to the Dependencies tab, and click the add "+" sign -> Library -> Java-> choose JavaFX from the list and click Add Selected, then Apply settings.

  2. Right click source file (src) in your JavaFX project, and create a new module-info.java file. Inside the file write the following code :

    module YourProjectName { 
        requires javafx.fxml;
        requires javafx.controls;
        requires javafx.graphics;
        opens sample;
    }
    

    These 2 steps will solve all your issues with JavaFX, I assure you.

Reference : There's a You Tube tutorial made by The Learn Programming channel, will explain all the details above in just 5 minutes. I also recommend watching it to solve your problem: https://www.youtube.com/watch?v=WtOgoomDewo

Difference between OpenJDK and Adoptium/AdoptOpenJDK

In short:

  • OpenJDK has multiple meanings and can refer to:
    • free and open source implementation of the Java Platform, Standard Edition (Java SE)
    • open source repository — the Java source code aka OpenJDK project
    • prebuilt OpenJDK binaries maintained by Oracle
    • prebuilt OpenJDK binaries maintained by the OpenJDK community
  • AdoptOpenJDK — prebuilt OpenJDK binaries maintained by community (open source licensed)

Explanation:

Prebuilt OpenJDK (or distribution) — binaries, built from http://hg.openjdk.java.net/, provided as an archive or installer, offered for various platforms, with a possible support contract.

OpenJDK, the source repository (also called OpenJDK project) - is a Mercurial-based open source repository, hosted at http://hg.openjdk.java.net. The Java source code. The vast majority of Java features (from the VM and the core libraries to the compiler) are based solely on this source repository. Oracle have an alternate fork of this.

OpenJDK, the distribution (see the list of providers below) - is free as in beer and kind of free as in speech, but, you do not get to call Oracle if you have problems with it. There is no support contract. Furthermore, Oracle will only release updates to any OpenJDK (the distribution) version if that release is the most recent Java release, including LTS (long-term support) releases. The day Oracle releases OpenJDK (the distribution) version 12.0, even if there's a security issue with OpenJDK (the distribution) version 11.0, Oracle will not release an update for 11.0. Maintained solely by Oracle.

Some OpenJDK projects - such as OpenJDK 8 and OpenJDK 11 - are maintained by the OpenJDK community and provide releases for some OpenJDK versions for some platforms. The community members have taken responsibility for releasing fixes for security vulnerabilities in these OpenJDK versions.

AdoptOpenJDK, the distribution is very similar to Oracle's OpenJDK distribution (in that it is free, and it is a build produced by compiling the sources from the OpenJDK source repository). AdoptOpenJDK as an entity will not be backporting patches, i.e. there won't be an AdoptOpenJDK 'fork/version' that is materially different from upstream (except for some build script patches for things like Win32 support). Meaning, if members of the community (Oracle or others, but not AdoptOpenJDK as an entity) backport security fixes to updates of OpenJDK LTS versions, then AdoptOpenJDK will provide builds for those. Maintained by OpenJDK community.

OracleJDK - is yet another distribution. Starting with JDK12 there will be no free version of OracleJDK. Oracle's JDK distribution offering is intended for commercial support. You pay for this, but then you get to rely on Oracle for support. Unlike Oracle's OpenJDK offering, OracleJDK comes with longer support for LTS versions. As a developer you can get a free license for personal/development use only of this particular JDK, but that's mostly a red herring, as 'just the binary' is basically the same as the OpenJDK binary. I guess it means you can download security-patched versions of LTS JDKs from Oracle's websites as long as you promise not to use them commercially.

Note. It may be best to call the OpenJDK builds by Oracle the "Oracle OpenJDK builds".

Donald Smith, Java product manager at Oracle writes:

Ideally, we would simply refer to all Oracle JDK builds as the "Oracle JDK", either under the GPL or the commercial license, depending on your situation. However, for historical reasons, while the small remaining differences exist, we will refer to them separately as Oracle’s OpenJDK builds and the Oracle JDK.


OpenJDK Providers and Comparison

----------------------------------------------------------------------------------------
|     Provider      | Free Builds | Free Binary   | Extended | Commercial | Permissive |
|                   | from Source | Distributions | Updates  | Support    | License    |
|--------------------------------------------------------------------------------------|
| AdoptOpenJDK      |    Yes      |    Yes        |   Yes    |   No       |   Yes      |
| Amazon – Corretto |    Yes      |    Yes        |   Yes    |   No       |   Yes      |
| Azul Zulu         |    No       |    Yes        |   Yes    |   Yes      |   Yes      |
| BellSoft Liberica |    No       |    Yes        |   Yes    |   Yes      |   Yes      |
| IBM               |    No       |    No         |   Yes    |   Yes      |   Yes      |
| jClarity          |    No       |    No         |   Yes    |   Yes      |   Yes      |
| OpenJDK           |    Yes      |    Yes        |   Yes    |   No       |   Yes      |
| Oracle JDK        |    No       |    Yes        |   No**   |   Yes      |   No       |
| Oracle OpenJDK    |    Yes      |    Yes        |   No     |   No       |   Yes      |
| ojdkbuild         |    Yes      |    Yes        |   No     |   No       |   Yes      |
| RedHat            |    Yes      |    Yes        |   Yes    |   Yes      |   Yes      |
| SapMachine        |    Yes      |    Yes        |   Yes    |   Yes      |   Yes      |
----------------------------------------------------------------------------------------

Free Builds from Source - the distribution source code is publicly available and one can assemble its own build

Free Binary Distributions - the distribution binaries are publicly available for download and usage

Extended Updates - aka LTS (long-term support) - Public Updates beyond the 6-month release lifecycle

Commercial Support - some providers offer extended updates and customer support to paying customers, e.g. Oracle JDK (support details)

Permissive License - the distribution license is non-protective, e.g. Apache 2.0


Which Java Distribution Should I Use?

In the Sun/Oracle days, it was usually Sun/Oracle producing the proprietary downstream JDK distributions based on OpenJDK sources. Recently, Oracle had decided to do their own proprietary builds only with the commercial support attached. They graciously publish the OpenJDK builds as well on their https://jdk.java.net/ site.

What is happening starting JDK 11 is the shift from single-vendor (Oracle) mindset to the mindset where you select a provider that gives you a distribution for the product, under the conditions you like: platforms they build for, frequency and promptness of releases, how support is structured, etc. If you don't trust any of existing vendors, you can even build OpenJDK yourself.

Each build of OpenJDK is usually made from the same original upstream source repository (OpenJDK “the project”). However each build is quite unique - $free or commercial, branded or unbranded, pure or bundled (e.g., BellSoft Liberica JDK offers bundled JavaFX, which was removed from Oracle builds starting JDK 11).

If no environment (e.g., Linux) and/or license requirement defines specific distribution and if you want the most standard JDK build, then probably the best option is to use OpenJDK by Oracle or AdoptOpenJDK.


Additional information

Time to look beyond Oracle's JDK by Stephen Colebourne

Java Is Still Free by Java Champions community (published on September 17, 2018)

Java is Still Free 2.0.0 by Java Champions community (published on March 3, 2019)

Aleksey Shipilev about JDK updates interview by Opsian (published on June 27, 2019)

Xcode 10: A valid provisioning profile for this executable was not found

I have tried all the above solutions.

However, in my case, after hours of headache it was because of the Test Project does not have a valid account for provisioning the signing. After I selected a team to provision in the Test Project with automatic managed signing. This problem went away.

How to reload current page?

Not really refreshing the page but thought it would help someone else out there looking for something simple

ngOnInit(){
    startUp()
}

startUp(){
    // Codes
}

refresh(){
    // Code to destroy child component
    startUp()
}

Center content vertically on Vuetify

In Vuetify 2.x, v-layout and v-flex are replaced by v-row and v-col respectively. To center the content both vertically and horizontally, we have to instruct the v-row component to do it:

<v-container fill-height>
    <v-row justify="center" align="center">
        <v-col cols="12" sm="4">
            Centered both vertically and horizontally
        </v-col>
    </v-row>
</v-container>
  • align="center" will center the content vertically inside the row
  • justify="center" will center the content horizontally inside the row
  • fill-height will center the whole content compared to the page.

OpenJDK8 for windows

Go to this link

Download version tar.gz for windows and just extract files to the folder by your needs. On the left pane, you can select which version of openjdk to download

Tutorial: unzip as expected. You need to set system variable PATH to include your directory with openjdk so you can type java -version in console.

JDK vs OpenJDK

System has not been booted with systemd as init system (PID 1). Can't operate

If you are using Docker, you may try an image that has Ubuntu with System D already active with this command:

docker run -d --name redis --privileged -v /sys/fs/cgroup:/sys/fs/cgroup:ro jrei/systemd-ubuntu:18.04

Then you just need to run:

docker exec -it redis /bin/bash

and there you can just install Redis, start it, restart it or whatever you need.

Flutter - The method was called on null

You should declare your method first in void initState(), so when the first time pages has been loaded, it will init your method first, hope it can help

How to convert string to boolean in typescript Angular 4

I have been trying different values with JSON.parse(value) and it seems to do the work:

// true
Boolean(JSON.parse("true"));
Boolean(JSON.parse("1"));
Boolean(JSON.parse(1));
Boolean(JSON.parse(true));

// false
Boolean(JSON.parse("0")); 
Boolean(JSON.parse(0));
Boolean(JSON.parse("false"));
Boolean(JSON.parse(false));

What is the Record type in typescript?

A Record lets you create a new type from a Union. The values in the Union are used as attributes of the new type.

For example, say I have a Union like this:

type CatNames = "miffy" | "boris" | "mordred";

Now I want to create an object that contains information about all the cats, I can create a new type using the values in the CatName Union as keys.

type CatList = Record<CatNames, {age: number}>

If I want to satisfy this CatList, I must create an object like this:

const cats:CatList = {
  miffy: { age:99 },
  boris: { age:16 },
  mordred: { age:600 }
}

You get very strong type safety:

  • If I forget a cat, I get an error.
  • If I add a cat that's not allowed, I get an error.
  • If I later change CatNames, I get an error. This is especially useful because CatNames is likely imported from another file, and likely used in many places.

Real-world React example.

I used this recently to create a Status component. The component would receive a status prop, and then render an icon. I've simplified the code quite a lot here for illustrative purposes

I had a union like this:

type Statuses = "failed" | "complete";

I used this to create an object like this:

const icons: Record<
  Statuses,
  { iconType: IconTypes; iconColor: IconColors }
> = {
  failed: {
    iconType: "warning",
    iconColor: "red"
  },
  complete: {
    iconType: "check",
    iconColor: "green"
  };

I could then render by destructuring an element from the object into props, like so:

const Status = ({status}) => <Icon {...icons[status]} />

If the Statuses union is later extended or changed, I know my Status component will fail to compile and I'll get an error that I can fix immediately. This allows me to add additional error states to the app.

Note that the actual app had dozens of error states that were referenced in multiple places, so this type safety was extremely useful.

How to allow all Network connection types HTTP and HTTPS in Android (9) Pie?

Easy Way

Add usesCleartextTraffic to AndroidManifest.xml

<application
...
android:usesCleartextTraffic="true"
...>

Indicates whether the app intends to use cleartext network traffic, such as cleartext HTTP. The default value for apps that target API level 27 or lower is "true". Apps that target API level 28 or higher default to "false".

How do I install opencv using pip?

run the following command by creating a virtual enviroment using python 3 and run

pip3 install opencv-python

to check it has installed correctly run

python3 -c "import cv2"

Find the smallest positive integer that does not occur in a given sequence

How about just playing around with loops.

import java.util.Arrays;
public class SmallestPositiveNumber {

    public int solution(int[] A) {
        Arrays.sort(A);
        int SPI = 1;

        if(A.length <= 1) return SPI;

        for(int i=0; i<A.length-1; i++){

            if((A[i+1] - A[i]) > 1)
            {
                return A[i] + 1;
            }
        }
        return A[A.length-1]+1;
    }
}

Waiting for another flutter command to release the startup lock

I have the same issue, I tried all the above solutions, but none of them worked for me. Then I searched the keywords in flutter directory, and found the following code. So I tried to delete bin/cache/.upgrade_lock, and it worked finally.

enter image description here

Under which circumstances textAlign property works in Flutter?

Set alignment: Alignment.centerRight in Container:

Container(
    alignment: Alignment.centerRight,
    child:Text(
       "Hello",
    ),
)

Deprecated Gradle features were used in this build, making it incompatible with Gradle 5.0

On a SpringBoot project using IntelliJ and Gradle, I got the warning "Deprecated Gradle features were used in this build, making it incompatible with Gradle 5.0" when running my integration test. What solved the problem was: - Going to: File > Settings > Build, Execution, Deployment - Selecting for "Build and run using": Intellij IDEA (instead of "Gradle") - Same for "Run tests using" That did not explain why Gradle is displaying the warning, but that let me perform the test and progress in my work.

Please run `npm cache clean`

This error can be due to many many things.

The key here seems the hint about error reading. I see you are working on a flash drive or something similar? Try to run the install on a local folder owned by your current user.

You could also try with sudo, that might solve a permission problem if that's the case.

Another reason why it cannot read could be because it has not downloaded correctly, or saved correctly. A little problem in your network could have caused that, and the cache clean would remove the files and force a refetch but that does not solve your problem. That means it would be more on the save part, maybe it didn't save because of permissions, maybe it didn't not save correctly because it was lacking disk space...

Confirm password validation in Angular 6

My answer is very simple>i have created password and confirm password validation using template driiven in angular 6

My html file

<div class="form-group">
  <label class="label-sm">Confirm Password</label>
  <input class="form-control" placeholder="Enter Password" type="password" #confirm_password="ngModel" [(ngModel)]="userModel.confirm_password" name="confirm_password" required (keyup)="checkPassword($event)" />
  <div *ngIf="confirm_password.errors && (confirm_password.dirty||confirm_password.touched||signup.submitted)">
  <div class="error" *ngIf="confirm_password.errors.required">Please confirm your password</div>
  </div>
  <div *ngIf="i" class='error'>Password does not match</div>
</div>

My typescript file

      public i: boolean;

      checkPassword(event) {
        const password = this.userModel.password;
        const confirm_new_password = event.target.value;

        if (password !== undefined) {
          if (confirm_new_password !== password) {
            this.i = true;
          } else {
            this.i = false;
          }
        }
      }

when clicking on submit button i check whether value of i is true or false

if true

if (this.i) {
      return false;
    }

else{
**form submitted code comes here**
}

Rounded Corners Image in Flutter

Use ClipRRect it will resolve your problem.

      ClipRRect(
              borderRadius: BorderRadius.all(Radius.circular(10.0)),
              child: Image.network(
                Constant.SERVER_LINK + model.userProfilePic,
                fit: BoxFit.cover,
              ),
            ),

Error: JavaFX runtime components are missing, and are required to run this application with JDK 11

This worked for me:

File >> Project Structure >> Modules >> Dependency >> + (on left-side of window)

clicking the "+" sign will let you designate the directory where you have unpacked JavaFX's "lib" folder.

Scope is Compile (which is the default.) You can then edit this to call it JavaFX by double-clicking on the line.

then in:

Run >> Edit Configurations

Add this line to VM Options:

--module-path /path/to/JavaFX/lib --add-modules=javafx.controls

(oh and don't forget to set the SDK)

How can I add raw data body to an axios request?

The key is to use "Content-Type": "text/plain" as mentioned by @MadhuBhat.

axios.post(path, code, { headers: { "Content-Type": "text/plain" } }).then(response => {
    console.log(response);
});

A thing to note if you use .NET is that a raw string to a controller will return 415 Unsupported Media Type. To get around this you need to encapsulate the raw string in hyphens like this and send it as "Content-Type": "application/json":

axios.post(path, "\"" + code + "\"", { headers: { "Content-Type": "application/json" } }).then(response => {
    console.log(response);
});

C# Controller:

[HttpPost]
public async Task<ActionResult<string>> Post([FromBody] string code)
{
    return Ok(code);
}

https://weblog.west-wind.com/posts/2017/sep/14/accepting-raw-request-body-content-in-aspnet-core-api-controllers

You can also make a POST with query params if that helps:

.post(`/mails/users/sendVerificationMail`, null, { params: {
  mail,
  firstname
}})
.then(response => response.status)
.catch(err => console.warn(err));

This will POST an empty body with the two query params:

POST http://localhost:8000/api/mails/users/sendVerificationMail?mail=lol%40lol.com&firstname=myFirstName

Source: https://stackoverflow.com/a/53501339/3850405

How do I install the Nuget provider for PowerShell on a unconnected machine so I can install a nuget package from the PS command line?

Here is the script I use in a Dockerfile based on windows/servercore to achieve complete PowerShellGallery setup through Artifactory mirrors (require access to GitHub releases too)

ARG ONEGET_PACKAGEMANAGEMENT="https://artifactory/artifactory/github-releases/OneGet/oneget/releases/download/1.4/PackageManagement.zip"
ARG ONEGET_ZIPFILE="C:/PackageManagement.zip"
 
RUN $ProviderPath = 'C:/Program Files/PackageManagement/ProviderAssemblies/nuget/2.8.5.208/'; `
    Invoke-WebRequest -Uri ${Env:ONEGET_PACKAGEMANAGEMENT} -OutFile ${Env:ONEGET_ZIPFILE}; `
    Expand-Archive ${Env:ONEGET_ZIPFILE} -DestinationPath "C:/" -Force; `
    New-Item -ItemType "directory" -Path $ProviderPath -Force; `
    Move-Item -Path "C:/PackageManagement/fullclr/Microsoft.PackageManagement.NuGetProvider.dll" -Destination $ProviderPath -Force; `
    Remove-Item -Recurse -Force -Path "C:/PackageManagement",${Env:ONEGET_ZIPFILE}; `
    Install-PackageProvider -Name NuGet -RequiredVersion 2.8.5.208 -Force; `
    Register-PSRepository -Name "artifactory-powershellgallery-remote" -SourceLocation "https://artifactory/artifactory/api/nuget/powershellgallery-remote"; `
    Unregister-PSRepository -Name PSGallery;

Xcode couldn't find any provisioning profiles matching

I am now able to successfully build. Not sure exactly which step "fixed" things, but this was the sequence:

  • Tried automatic signing again. No go, so reverted to manual.
  • After reverting, I had no Eligible Profiles, all were ineligible. Strange.
  • I created a new certificate and profile, imported both. This too was "ineligible".
  • Removed the iOS platform and re-added it. I had tried this previously without luck.
  • After doing this, Xcode on its own defaulted to automatic signing. And this worked! Success!

While I am not sure exactly which parts were necessary, I think the previous certificates were the problem. I hate Xcode :(

Thanks for help.

Couldn't process file resx due to its being in the Internet or Restricted zone or having the mark of the web on the file

  1. Find the path from error log and open the file in explorer 2)select the file and right-click -> properties
  2. Then check the 'unblock' option and click on apply enter image description here

How to upgrade Python version to 3.7?

On ubuntu you can add this PPA Repository and use it to install python 3.7: https://launchpad.net/~jonathonf/+archive/ubuntu/python-3.7

Or a different PPA that provides several Python versions is Deadsnakes: https://launchpad.net/~deadsnakes/+archive/ubuntu/ppa

See also here: https://askubuntu.com/questions/865554/how-do-i-install-python-3-6-using-apt-get (I know it says 3.6 in the url, but the deadsnakes ppa also contains 3.7 so you can use it for 3.7 just the same)

If you want "official" you'd have to install it from the sources from the site, get the code (which you already downloaded) and do this:

tar -xf Python-3.7.0.tar.xz
cd Python-3.7.0
./configure
make
sudo make install        <-- sudo is required.

This might take a while

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured

If you are using YAML for configuration, then it might be indentation problem. Thoroughly check the YAML files.

Unable to resolve dependency for ':app@debug/compileClasspath': Could not resolve

I was unable to find the root cause of the issue but got a workaround. I started by setting my the java home variable as such.

  • vi ~/.bash_profile (this is for macs only. bash profiles are different on linux)
  • type the letter i for insert and then set the JAVA_HOME variable as such
  • export JAVA_HOME=/Applications/Android\Studio.app/Contents/jre/jdk/Contents/Home/
  • quit the vi editor with esc then type :wq
  • Restart the computer
  • Voila! Your android studio projects should build without any qualms

FirebaseInstanceIdService is deprecated

You have to use FirebaseMessagingService() instead of FirebaseInstanceIdService

Uncaught SyntaxError: Unexpected end of JSON input at JSON.parse (<anonymous>)

You are calling:

JSON.parse(scatterSeries)

But when you defined scatterSeries, you said:

var scatterSeries = []; 

When you try to parse it as JSON it is converted to a string (""), which is empty, so you reach the end of the string before having any of the possible content of a JSON text.

scatterSeries is not JSON. Do not try to parse it as JSON.

data is not JSON either (getJSON will parse it as JSON automatically).

ch is JSON … but shouldn't be. You should just create a plain object in the first place:

var ch = {
    "name": "graphe1",
    "items": data.results[1]
};

scatterSeries.push(ch);

In short, for what you are doing, you shouldn't have JSON.parse anywhere in your code. The only place it should be is in the jQuery library itself.

Everytime I run gulp anything, I get a assertion error. - Task function must be specified

https://fettblog.eu/gulp-4-parallel-and-series/

Because gulp.task(name, deps, func) was replaced by gulp.task(name, gulp.{series|parallel}(deps, func)).

You are using the latest version of gulp but older code. Modify the code or downgrade.

installation app blocked by play protect

the only solution worked for me was using java keytool and generating a .keystore file the command line and then use that .keystore file to sign my app

you can find the java keytool at this directory C:\Program Files\Java\jre7\bin

open a command window and switch to that directory and enter a command like this

keytool -genkey -v -keystore my-release-key.keystore -alias alias_name -keyalg RSA -keysize 2048 -validity 10000

Keytool prompts you to provide passwords for the keystore, your name , company etc . note that at the last prompt you need to enter yes.

It then generates the keystore as a file called my-release-key.keystore in the directory you're in. The keystore and key are protected by the passwords you entered. The keystore contains a single key, valid for 10000 days. The alias is a name that you — will use later, to refer to this keystore when signing your application.

For more information about Keytool, see the documentation at: http://docs.oracle.com/javase/6/docs/technotes/tools/windows/keytool.html

and for more information on signing Android apps go here: http://developer.android.com/tools/publishing/app-signing.html

Handling back button in Android Navigation Component

I have searched through many threads and none of them work. Finally I found one:

MainActivity.java

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    Toolbar mToolbar = findViewById(R.id.topAppBar);
    setSupportActionBar(mToolbar);
}

@Override
public boolean onSupportNavigateUp() {
    navController.navigateUp();
    return super.onSupportNavigateUp();
}

MyFragment.java

@Override
public void onViewCreated(@NonNull final View view, @Nullable Bundle savedInstanceState) {
    Toolbar mToolbar = (MainActivity) getActivity().findViewById(R.id.topAppBar);
    mToolbar.setNavigationOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            // Do something when uses presses back button (showing modals, messages,...)
            // Note that this will override behaviour of back button
        }
    });
}

@Override
public void onStop() {
    // Reset back button to default behaviour when we leave this fragment
    Toolbar mToolbar = (MainActivity) getActivity().findViewById(R.id.topAppBar);
    mToolbar.setNavigationOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            mainActivity.onBackPressed();
        }
    });

    super.onStop();
}

Enable CORS in fetch api

Browser have cross domain security at client side which verify that server allowed to fetch data from your domain. If Access-Control-Allow-Origin not available in response header, browser disallow to use response in your JavaScript code and throw exception at network level. You need to configure cors at your server side.

You can fetch request using mode: 'cors'. In this situation browser will not throw execption for cross domain, but browser will not give response in your javascript function.

So in both condition you need to configure cors in your server or you need to use custom proxy server.

Google Maps shows "For development purposes only"

You can't use iframe tag in HTML, here's what you can do:
* just go into google maps point out your location
* click on "Share"
* go to "Embed a map"
* copy the HTML code
* paste it in your HTML page
* adjust height and width according to your requirement
* run it

This might work

How to add image in Flutter

The problem is in your pubspec.yaml, here you need to delete the last comma.

uses-material-design: true,

Bootstrap 4 multiselect dropdown

Because the bootstrap-select is a bootstrap component and therefore you need to include it in your code as you did for your V3

NOTE: this component only works in since version 1.13.0

_x000D_
_x000D_
$('select').selectpicker();
_x000D_
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css">_x000D_
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.13.1/css/bootstrap-select.css" />_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.bundle.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.13.1/js/bootstrap-select.min.js"></script>_x000D_
_x000D_
_x000D_
_x000D_
<select class="selectpicker" multiple data-live-search="true">_x000D_
  <option>Mustard</option>_x000D_
  <option>Ketchup</option>_x000D_
  <option>Relish</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

Cross-Origin Read Blocking (CORB)

Response headers are generally set on the server. Set 'Access-Control-Allow-Headers' to 'Content-Type' on server side

curl: (35) error:1408F10B:SSL routines:ssl3_get_record:wrong version number

Simple answer

If you are behind a proxy server, please set the proxy for curl. The curl is not able to connect to server so it shows wrong version number. Set proxy by opening subl ~/.curlrc or use any other text editor. Then add the following line to file: proxy= proxyserver:proxyport For e.g. proxy = 10.8.0.1:8080

If you are not behind a proxy, make sure that the curlrc file does not contain the proxy settings.

Android design support library for API 28 (P) not working

Try this:

implementation 'com.android.support:appcompat-v7:28.0.0-alpha1'

Trying to merge 2 dataframes but get ValueError

I found that my dfs both had the same type column (str) but switching from join to merge solved the issue.

On npm install: Unhandled rejection Error: EACCES: permission denied

change ownership

sudo chown -R $USER:$GROUP ~/.npm
sudo chown -R $USER:$GROUP ~/.config 

worked for as i installed package using sudo

How to install OpenSSL in windows 10?

Check openssl tool which is a collection of Openssl from the LibreSSL project and Cygwin libraries (2.5 MB). NB! We're the packager.

One liner to create a self signed certificate:

openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout selfsigned.key -out selfsigned.crt

Difference between npx and npm?

Introducing npx: an npm package runner

NPM - Manages packages but doesn't make life easy executing any.
NPX - A tool for executing Node packages.

NPX comes bundled with NPM version 5.2+

NPM by itself does not simply run any package. it doesn't run any package in a matter of fact. If you want to run a package using NPM, you must specify that package in your package.json file.

When executables are installed via NPM packages, NPM links to them:

  1. local installs have "links" created at ./node_modules/.bin/ directory.
  2. global installs have "links" created from the global bin/ directory (e.g. /usr/local/bin) on Linux or at %AppData%/npm on Windows.

Documentation you should read


NPM:

One might install a package locally on a certain project:

npm install some-package

Now let's say you want NodeJS to execute that package from the command line:

$ some-package

The above will fail. Only globally installed packages can be executed by typing their name only.

To fix this, and have it run, you must type the local path:

$ ./node_modules/.bin/some-package

You can technically run a locally installed package by editing your packages.json file and adding that package in the scripts section:

{
  "name": "whatever",
  "version": "1.0.0",
  "scripts": {
    "some-package": "some-package"
  }
}

Then run the script using npm run-script (or npm run):

npm run some-package

NPX:

npx will check whether <command> exists in $PATH, or in the local project binaries, and execute it. So, for the above example, if you wish to execute the locally-installed package some-package all you need to do is type:

npx some-package

Another major advantage of npx is the ability to execute a package which wasn't previously installed:

$ npx create-react-app my-app

The above example will generate a react app boilerplate within the path the command had run in, and ensures that you always use the latest version of a generator or build tool without having to upgrade each time you’re about to use it.


Use-Case Example:

npx command may be helpful in the script section of a package.json file, when it is unwanted to define a dependency which might not be commonly used or any other reason:

"scripts": {
    "start": "npx [email protected]",
    "serve": "npx http-server"
}

Call with: npm run serve


Related questions:

  1. How to use package installed locally in node_modules?
  2. NPM: how to source ./node_modules/.bin folder?
  3. How do you run a js file using npm scripts?

Failed to resolve: com.google.firebase:firebase-core:16.0.1

if you are using

compileSdkVersion 23

in app-level gradle, and

classpath 'com.android.tools.build:gradle:2.1.0'

in project-level gradle and you have added the google-services.json file to your project.

you need to add just below code

maven {
   url "https://maven.google.com"
}

at below of jcenter() in repositories blocks in project-level gradle file here are my gradle files:

project-level gradle file:

buildscript {
    repositories {
        jcenter()
        maven {
            url "https://maven.google.com"
        }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.1.0'
        classpath 'com.google.gms:google-services:4.0.1'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
        maven {
            url "https://maven.google.com"
        }
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

and app-level gradle file:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.3"

    defaultConfig {
        applicationId "com.example.moslem.amazonlikeapp"
        minSdkVersion 21
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.3.0'
    compile 'com.google.firebase:firebase-core:16.0.1'
}
apply plugin: 'com.google.gms.google-services'

Authentication plugin 'caching_sha2_password' is not supported

You can go to Settings->Project->Project Interpreter and here install latest version of mysql-connector-python package. In my case it was mysql-connector-python 8.0.15.

How do I center text vertically and horizontally in Flutter?

If you are a intellij IDE user, you can use shortcut key Alt+Enter and then choose Wrap with Center and then add textAlign: TextAlign.center

Flutter Circle Design

you can use decoration like this :

   Container(
                    width: 60,
                    height: 60,
                    child: Icon(CustomIcons.option, size: 20,),
                    decoration: BoxDecoration(
                        shape: BoxShape.circle,
                        color: Color(0xFFe0f2f1)),
                  )

Now you have circle shape and Icon on it.

enter image description here

Can not find module “@angular-devkit/build-angular”

I've just encountered this problem and fixed it. I think the root cause of this problem is ng and current version of node.js (10.6.0) and accompanying npm are not in sync. I've installed the LTS version of node.js (8.11.3) and the problem disappeared.

Could not find module "@angular-devkit/build-angular"

For Angular 8

Install npm-check-updates package

Run:

$ npm i npm-check-updates
$ ncu -u
$ npm install

This package will update all packages and resolve this issue

Notice: After update If you face this issue:

ERROR in The Angular Compiler requires TypeScript >=3.4.0 and <3.6.0 but 3.6.3 was found instead.

then run:

$ npm install [email protected]

Source Link

How to remove package using Angular CLI?

npm uninstal @angular/material

and also clear file custom-theme.scss

How to use the new Material Design Icon themes: Outlined, Rounded, Two-Tone and Sharp?

For angular material you should use fontSet input to change the font family:

<link href="https://fonts.googleapis.com/css?family=Material+Icons|Material+Icons+Outlined|Material+Icons+Two+Tone|Material+Icons+Round|Material+Icons+Sharp"
rel="stylesheet" />

<mat-icon>edit</mat-icon>
<mat-icon fontSet="material-icons-outlined">edit</mat-icon>
<mat-icon fontSet="material-icons-two-tone">edit</mat-icon>
...

How to add bootstrap in angular 6 project?

npm install --save bootstrap

afterwards, inside angular.json (previously .angular-cli.json) inside the project's root folder, find styles and add the bootstrap css file like this:

for angular 6

"styles": [
          "../node_modules/bootstrap/dist/css/bootstrap.min.css",
          "styles.css"
],

for angular 7

"styles": [
          "node_modules/bootstrap/dist/css/bootstrap.min.css",
          "src/styles.css"
],

Can't bind to 'dataSource' since it isn't a known property of 'table'

The problem is your angular material version, I have the same, and I have resolved this when I have installed the good version of angular material in local.

Hope it solve yours too.

Conflict with dependency 'com.android.support:support-annotations' in project ':app'. Resolved versions for app (26.1.0) and test app (27.1.1) differ.

Another simple way to solve this problem is to edit your build.gradle (app):

  1. Go to android tag and change compileSdkVersion 26 to compileSdkVersion 27
  2. Go to defaultConfig tag and change targetSdkVersion 26 to targetSdkVersion 27
  3. Got to dependencies tag and change implementation 'com.android.support:appcompat-v7:26.1.0' to implementation 'com.android.support:appcompat-v7:27.1.1'

MySQL 8.0 - Client does not support authentication protocol requested by server; consider upgrading MySQL client

In MySQL 8.0, caching_sha2_password is the default authentication plugin rather than mysql_native_password. ...

Most of the answers in this question result in a downgrade to the authentication mechanism from caching_sha2_password to mysql_native_password. From a security perspective, this is quite disappointing.

This document extensively discusses caching_sha2_password and of course why it should NOT be a first choice to downgrade the authentication method.

With that, I believe Aidin's answer should be the accepted answer. Instead of downgrading the authentication method, use a connector which matches the server's version instead.

Create a button with rounded border

For implementing the rounded border button with a border color use this

OutlineButton(
                    child: new Text("Button Text"),borderSide: BorderSide(color: Colors.blue),
                    onPressed: null,
                    shape: new RoundedRectangleBorder(borderRadius: new BorderRadius.circular(20.0))
                ),

php mysqli_connect: authentication method unknown to the client [caching_sha2_password]

I think it is not useful to configure the mysql server without caching_sha2_password encryption, we have to find a way to publish, send or obtain secure information through the network. As you see in the code below I dont use variable $db_name, and Im using a user in mysql server with standar configuration password. Just create a Standar user password and config all privilages. it works, but how i said without segurity.

<?php
$db_name="db";
$mysql_username="root";
$mysql_password="****";
$server_name="localhost";
$conn=mysqli_connect($server_name,$mysql_username,$mysql_password);

if ($conn) {
    echo "connetion success";
}
else{
    echo mysqli_error($conn);
}

?>

ERROR Error: StaticInjectorError(AppModule)[UserformService -> HttpClient]:

Simply i have import in appmodule.ts

import { HttpClientModule } from '@angular/common/http';
  imports: [
     BrowserModule,
     FormsModule,
     HttpClientModule  <<<this 
  ],

My problem resolved

Access IP Camera in Python OpenCV

To access an Ip Camera, first, I recommend you to install it like you are going to use for the standard application, without any code, using normal software.

After this, you have to know that for different cameras, we have different codes. There is a website where you can see what code you can use to access them:

https://www.ispyconnect.com/sources.aspx

But be careful, for my camera (Intelbras S3020) it does not work. The right way is to ask the company of your camera, and if they are a good company they will provide it.

When you know your code just add it like:

cap = cv2.VideoCapture("http://LOGIN:PASSWORD@IP/cgi-bin/mjpg/video.cgi?&subtype=1")

Instead LOGIN you will put your login, and instead PASSWORD you will put your password.

To find out camera's IP address there is many softwares that you can download and provide the Ip address to you. I use the software from Intelbras, but I also recommend EseeCloud because they work for almost all cameras that I've bought:

https://eseecloud.software.informer.com/1.2/

In this example, it shows the protocol http to access the Ip camera, but you can also use rstp, it depends on the camera, as I said.

If you have any further questions just let me know.

phpMyAdmin on MySQL 8.0

Create another user with mysql_native_password option:

In terminal:

mysql> CREATE USER 'su'@'localhost' IDENTIFIED WITH mysql_native_password BY '123';
mysql> GRANT ALL PRIVILEGES ON * . * TO 'su'@'localhost';
mysql> FLUSH PRIVILEGES;

You must add a reference to assembly 'netstandard, Version=2.0.0.0

I had to do a combination of other people's answers on this thread.

  1. Install the NetStandard.Library via NuGet
  2. Manually editing the .csproj file and adding the reference. <Reference Include="netstandard" />
  3. Expanding project-->References in the VS Solution Explorer, right clicking on 'netstandard' and showing the properties page and setting "Copy Local" to true.

Angular - "has no exported member 'Observable'"

Apparently (as you point in the error log), after updating to Angular 6.0.0 rxjs-compat is missing.

Run npm install rxjs-compat --save to install. Should fix it.

How to upgrade docker-compose to latest version

If you tried sudo apt-get remove docker-compose and get E: Unable to locate package docker-compose, try this method :

This command must return a result, in order to check it is installed here :

ls -l /usr/local/bin/docker-compose

Remove the old version :

sudo rm -rf docker-compose

Download the last version (check official repo : docker/compose/releases) :

sudo curl -L "https://github.com/docker/compose/releases/download/1.24.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose

(replace 1.24.0 if needed)

Finally, apply executable permissions to the binary:

sudo chmod +x /usr/local/bin/docker-compose

Check version :

docker-compose -v

Error: Local workspace file ('angular.json') could not be found

Uninstall the old version of Angular cli, and install Angular CLI global:

Update Angular cli global package to the next version, "@angular/compiler-cli": "^6.0.0"

npm uninstall -g @angular/cli
npm cache verify
npm install -g @angular/cli@next

Generate a new project and default application by running the following command:

ng new my-project
cd my-project
ng serve

Flutter.io Android License Status Unknown

Refer--https://robbinespu.gitlab.io/blog/2020/03/03/flutter-issue-fixed-android-license-status-unknown-on-windows/

So here the solution, open your SDK manager then uncheck Hide Obsolete Packages

enter image description here

Now you’ll see Android SDK Tools (Obsolete) 26.1.1 appears. Tick that package and hit apply button then ok button. it will download sdk. then restart Android studio

Nice, now if you run flutter doctor, you should get positive result as below

PS D:\Workplace\flutter_projects> flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[v] Flutter (Channel stable, v1.12.13+hotfix.8, on Microsoft Windows [Version 10.0.18363.657], locale en-MY)

[v] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
[v] Android Studio (version 3.6)
[v] VS Code (version 1.42.1)
[v] Connected device (1 available)

• No issues found!

PS D:\Workplace\flutter_projects> flutter doctor --android-licenses -v
All SDK package licenses accepted.======] 100% Computing updates...

Run flutter doctor --android-licenses and enter Y when is asked

if needed we can download package manually here https://dl.google.com/android/repository/sdk-tools-windows-4333796.zip (for Windows user). Hope this tutorial help people who looking for solution

'pip install' fails for every package ("Could not find a version that satisfies the requirement")

Support for TLS 1.0 and 1.1 was dropped for PyPI. If your system does not use a more recent version, it could explain your error.

Could you try reinstalling pip system-wide, to update your system dependencies to a newer version of TLS?

This seems to be related to Unable to install Python libraries

See Dominique Barton's answer:

Apparently pip is trying to access PyPI via HTTPS (which is encrypted and fine), but with an old (insecure) SSL version. Your system seems to be out of date. It might help if you update your packages.

On Debian-based systems I'd try:

apt-get update && apt-get upgrade python-pip

On Red Hat Linux-based systems:

yum update python-pip # (or python2-pip, at least on Red Hat Linux 7)

On Mac:

sudo easy_install -U pip

You can also try to update openssl separately.

What is {this.props.children} and when you should use it?

What even is ‘children’?

The React docs say that you can use props.children on components that represent ‘generic boxes’ and that don’t know their children ahead of time. For me, that didn’t really clear things up. I’m sure for some, that definition makes perfect sense but it didn’t for me.

My simple explanation of what this.props.children does is that it is used to display whatever you include between the opening and closing tags when invoking a component.

A simple example:

Here’s an example of a stateless function that is used to create a component. Again, since this is a function, there is no this keyword so just use props.children

const Picture = (props) => {
  return (
    <div>
      <img src={props.src}/>
      {props.children}
    </div>
  )
}

This component contains an <img> that is receiving some props and then it is displaying {props.children}.

Whenever this component is invoked {props.children} will also be displayed and this is just a reference to what is between the opening and closing tags of the component.

//App.js
render () {
  return (
    <div className='container'>
      <Picture key={picture.id} src={picture.src}>
          //what is placed here is passed as props.children  
      </Picture>
    </div>
  )
}

Instead of invoking the component with a self-closing tag <Picture /> if you invoke it will full opening and closing tags <Picture> </Picture> you can then place more code between it.

This de-couples the <Picture> component from its content and makes it more reusable.

Reference: A quick intro to React’s props.children

Property '...' has no initializer and is not definitely assigned in the constructor

It is because TypeScript 2.7 includes a strict class checking where all the properties should be initialized in the constructor. A workaround is to add the ! as a postfix to the variable name:

makes!: any[];

Extract Google Drive zip from Google colab notebook

For Python

Connect to drive,

from google.colab import drive
drive.mount('/content/drive')

Check for directory

!ls and !pwd

For unzip

!unzip drive/"My Drive"/images.zip

Angular 5 ngHide ngShow [hidden] not working

If you add [hidden]="true" to div, the actual thing that happens is adding a class [hidden] to this element conditionally with display: none

Please check the style of the element in the browser to ensure no other style affect the display property of an element like this:

enter image description here

If you found display of [hidden] class is overridden, you need to add this css code to your style:

[hidden] {
    display: none !important;
}

How to use lifecycle method getDerivedStateFromProps as opposed to componentWillReceiveProps

As we recently posted on the React blog, in the vast majority of cases you don't need getDerivedStateFromProps at all.

If you just want to compute some derived data, either:

  1. Do it right inside render
  2. Or, if re-calculating it is expensive, use a memoization helper like memoize-one.

Here's the simplest "after" example:

import memoize from "memoize-one";

class ExampleComponent extends React.Component {
  getDerivedData = memoize(computeDerivedState);

  render() {
    const derivedData = this.getDerivedData(this.props.someValue);
    // ...
  }
}

Check out this section of the blog post to learn more.

How to open Android Device Monitor in latest Android Studio 3.1

Android Device Monitor was deprecated in Android Studio 3.1 and removed from Android Studio 3.2

Use Android Profiler introduced in Android Studio 3.0 to measure the cpu utilisation, network, memory etc,. To open Android Profiler: View -> Tool Windows -> Profiler.

Android Device Monitor has been replaced by some new feature which you can find here.

Default interface methods are only supported starting with Android N

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'


android {
compileSdkVersion 30
buildToolsVersion "30.0.0"

compileOptions {
    sourceCompatibility JavaVersion.VERSION_1_8
    targetCompatibility JavaVersion.VERSION_1_8
}

defaultConfig {
    applicationId "com.example.architecture"
    minSdkVersion 16
    targetSdkVersion 30
    versionCode 1
    versionName "1.0"

    testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
 buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
    }
   }
}
dependencies {

implementation 'androidx.room:room-runtime:2.2.5'
implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
annotationProcessor 'androidx.room:room-compiler:2.2.5'
def lifecycle_version = "2.2.0"
def arch_version = "2.1.0"

implementation fileTree(dir: "libs", include: ["*.jar"])
implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
implementation 'androidx.core:core-ktx:1.3.0'
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:$lifecycle_version"
implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"
implementation "androidx.lifecycle:lifecycle-service:$lifecycle_version"
implementation "androidx.lifecycle:lifecycle-process:$lifecycle_version"
implementation "androidx.cardview:cardview:1.0.0"
}

Add the configuration in your app module's build.gradle

android {
    ...
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
}

Round button with text and icon in flutter

If You need the text to be centered, and the image to be besides it, like this: Flutter RaisedButton with image and centered text

Then You can achieve it with this widget tree:

RaisedButton(
  onPressed: () {},
  child: Row(
    mainAxisAlignment: MainAxisAlignment.spaceBetween,
    children: <Widget>[
      Expanded(child: Text(
        'Push it! '*10,
        textAlign: TextAlign.center,
      ),),
      Image.network(
        'https://picsum.photos/250?image=9',
      ),
    ],
  ),
),

Full example available on my dartpad.dev (link).

Converting a POSTMAN request to Curl

enter image description here

You can see the button "Code" in the attached screenshot, press it and you can get your code in many different languages including PHP cURL

enter image description here

What could cause an error related to npm not being able to find a file? No contents in my node_modules subfolder. Why is that?

Try the following steps:
1. Make sure you have the latest npm (npm install -g npm).
2. Add an exception to your antivirus to ignore the node_modules folder in your project.
3. $ rm -rf node_modules package-lock.json .
4. $ npm install

Unable to compile simple Java 10 / Java 11 project with Maven

UPDATE

The answer is now obsolete. See this answer.


maven-compiler-plugin depends on the old version of ASM which does not support Java 10 (and Java 11) yet. However, it is possible to explicitly specify the right version of ASM:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.7.0</version>
    <configuration>
        <release>10</release>
    </configuration>
    <dependencies>
        <dependency>
            <groupId>org.ow2.asm</groupId>
            <artifactId>asm</artifactId>
            <version>6.2</version> <!-- Use newer version of ASM -->
        </dependency>
    </dependencies>
</plugin>

You can find the latest at https://search.maven.org/search?q=g:org.ow2.asm%20AND%20a:asm&core=gav

docker: Error response from daemon: Get https://registry-1.docker.io/v2/: Service Unavailable. IN DOCKER , MAC

I had this issue when I first installed Docker and ran

docker run hello-world

I was on a corporate network and switching to my personal network solved the issue for me.

Getting "TypeError: failed to fetch" when the request hasn't actually failed

I have a similar problem and as I'm newbie, here are some facts for somebody to comment:

I'm sending form data to Google sheet this way (scriptURL is https://script.google.com/macros/s/AKfy..., showSuccess() is showing a simple image):

fetch(scriptURL, {method: 'POST', body: new FormData(form)})
.then(response => showSuccess())
.catch(error => alert('Error! ' + error.message))

Executed in Edge my HTML doesn't show error and Network tab reports this 3 requests: Edge execution Executed in Chrome my HTML (index.htm) shows Failed to fetch error and Network tab reports this 2 requests: Chrome execution The value in the second column is blocked:other and there is also an error in Console tab:

GET https://script.googleusercontent.com/macros/echo?user_content_key=D-ABF... net::ERR_BLOCKED_BY_CLIENT

In order to suspend installed Chrome extensions, I executed my code in an Incognito window and there is no error message and Network tab reports this 2 requests: Incognito execution

My guess is that something (extension?) prevents Chrome to read the request's answer (the GET request is blocked).

How to set up devices for VS Code for a Flutter emulator

You can connect an Android Phone via USB cable and then it will show the device in the bottom bar.(Please note ADB must be installed. Click here for more)

Or you can completely install Android Studio and setup emulator from there and run the emulator. Then VS Code will recogzine the emulator and show at the bottom bar.

Error:(9, 5) error: resource android:attr/dialogCornerRadius not found

This Is Because compileSdkVersion , buildToolsVersion and Dependecies implementations are not match You Have to done like this i have 28 library then

compileSdkVersion 28
targetSdkVersion   28
buildToolsVersion  28.0.3
implementation 'com.android.support:design:28.0.0'
implementation 'com.android.support:appcompat-v7:28.0.0'

If we You Use Any where less than 28 this error should occured so please try match library in all.

How to clear Flutter's Build cache?

There are basically 3 alternatives to cleaning everything that you could try:

  • flutter clean will delete the /build folder.
  • Manually delete the /build folder, which is essentially the same as flutter clean.
  • Or, as @Rémi Roudsselet pointed out: restart your IDE, as it might be caching some older error logs and locking everything up.

Composer require runs out of memory. PHP Fatal error: Allowed memory size of 1610612736 bytes exhausted

I condensed or packaged up the useful and accepted answer here into reusable (zsh) aliases/functions, for quicker and easier-to-remember reuse:

# composer high-memory
composermem() {
  php -r "echo ini_get('memory_limit').PHP_EOL;"
}
alias composerbig='COMPOSER_MEMORY_LIMIT=-1 composer $1'

(php composer.phar is already aliased to composer on the system).

Flutter does not find android sdk

We need to manually add the Android SDK. The instructions in the flutter.io/download say that the Android Studio 3.6 or later needs the SDK to be installed manually. To do that,

  1. Open the Android Studio SDK Manager
  2. In the Android SDK tab, uncheck Hide Obsolete Packages
  3. Check Android SDK Tools (Obsolete)

Please refer the Android Setup Instructions.

How to remove whitespace from a string in typescript?

Trim just removes the trailing and leading whitespace. Use .replace(/ /g, "") if there are just spaces to be replaced.

this.maintabinfo = this.inner_view_data.replace(/ /g, "").toLowerCase();

Removing Conda environment

Because you can only deactivate the active environment, so conda deactivate does not need nor accept arguments. The error message is very explicit here.

Just call conda deactivate https://github.com/conda/conda/issues/7296#issuecomment-389504269

Error : Program type already present: android.support.design.widget.CoordinatorLayout$Behavior

Your build script should match with application build.gradle dependencies.

ext {
        buildToolsVersion = "27.0.3"
        minSdkVersion = 16
        compileSdkVersion = 27
        targetSdkVersion = 26
        supportLibVersion = "27.1.1"
    }


dependencies {
    .................
    ...................

    implementation 'com.android.support:support-v4:27.1.0'
    implementation 'com.android.support:design:27.1.0'
    ................
    ...........
}

if you want to downgrade dependencies then also downgrade supportLibVersion and buildToolsVersion .

After Spring Boot 2.0 migration: jdbcUrl is required with driverClassName

As this post gets a bit of popularity I edited it a bit. Spring Boot 2.x.x changed default JDBC connection pool from Tomcat to faster and better HikariCP. Here comes incompatibility, because HikariCP uses different property of jdbc url. There are two ways how to handle it:

OPTION ONE

There is very good explanation and workaround in spring docs:

Also, if you happen to have Hikari on the classpath, this basic setup does not work, because Hikari has no url property (but does have a jdbcUrl property). In that case, you must rewrite your configuration as follows:

app.datasource.jdbc-url=jdbc:mysql://localhost/test
app.datasource.username=dbuser
app.datasource.password=dbpass

OPTION TWO

There is also how-to in the docs how to get it working from "both worlds". It would look like below. ConfigurationProperties bean would do "conversion" for jdbcUrl from app.datasource.url

@Configuration
public class DatabaseConfig {
    @Bean
    @ConfigurationProperties("app.datasource")
    public DataSourceProperties dataSourceProperties() {
        return new DataSourceProperties();
    }

    @Bean
    @ConfigurationProperties("app.datasource")
    public HikariDataSource dataSource(DataSourceProperties properties) {
        return properties.initializeDataSourceBuilder().type(HikariDataSource.class)
                .build();
    }
}

Flutter: how to make a TextField with HintText but no Underline?

TextField widget has a property decoration which has a sub property border: InputBorder.none.This property would Remove TextField Text Input Bottom Underline in Flutter app. So you can set the border property of the decoration of the TextField to InputBorder.none, see here for an example:

border: InputBorder.none : Hide bottom underline from Text Input widget.

 Container(
        width: 280,
        padding: EdgeInsets.all(8.0),
        child : TextField(
                autocorrect: true,
                decoration: InputDecoration(
                border: InputBorder.none,
                hintText: 'Enter Some Text Here')
            )
    )

'ls' is not recognized as an internal or external command, operable program or batch file

We can use ls and many other Linux commands in Windows cmd. Just follow these steps.

Steps:

1) Install Git in your computer - https://git-scm.com/downloads.

2) After installing Git, go to the folder in which Git is installed. Mostly it will be in C drive and then Program Files Folder.

3) In Program Files folder, you will find the folder named Git, find the bin folder which is inside usr folder in the Git folder.

In my case, the location for bin folder was - C:\Program Files\Git\usr\bin

4) Add this location (C:\Program Files\Git\usr\bin) in path variable, in system environment variables.

5) You are done. Restart cmd and try to run ls and other Linux commands.

ERROR Source option 1.5 is no longer supported. Use 1.6 or later

You can specify maven source/target version by adding these properties to your pom.xml file

<properties>
    <maven.compiler.source>1.6</maven.compiler.source>
    <maven.compiler.target>1.6</maven.compiler.target>
</properties>

Cannot inline bytecode built with JVM target 1.8 into bytecode that is being built with JVM target 1.6

In my case, just changingTarget JVM Version like this: File > Setting > Kotlin Compiler > Target JVM Version > 1.8 did not help. However, it does resolved compile time error. But failed at runtime.

I also had to add following in app build.gradle file to make it work.

 android {
     // Other code here...
     kotlinOptions {
        jvmTarget = "1.8"
     }
 }

SSL_connect: SSL_ERROR_SYSCALL in connection to github.com:443

for me, that's caused by the SSL certificate not enabled in the K8S ingress. hope this helps someone

How to avoid the "Windows Defender SmartScreen prevented an unrecognized app from starting warning"

After clicking on Properties of any installer(.exe) which block your application to install (Windows Defender SmartScreen prevented an unrecognized app ) for that issue i found one solution

  1. Right click on installer(.exe)
  2. Select properties option.
  3. Click on checkbox to check Unblock at the bottom of Properties.

This solution work for Heroku CLI (heroku-x64) installer(.exe)

How to remove the Flutter debug banner?

how to remove debug banner in flutter

Just add debugShowCheckedModeBanner: false in MaterialApp.

3 ways - Remove Debug Banner In Flutter

js 'types' can only be used in a .ts file - Visual Studio Code using @ts-check

Use "javascript.validate.enable": false in your VS Code settings, It doesn't disable ESLINT. I use both ESLINT & Flow. Simply follow the instructions Flow For Vs Code Setup

Adding this line in settings.json. Helps "javascript.validate.enable": false

Entity Framework Core: A second operation started on this context before a previous operation completed

I have a background service that performs an action for each entry in a table. The problem is, that if I iterate over and modify some data all on the same instance of the DbContext this error occurs.

One solution, as mentioned in this thread is to change the DbContext's lifetime to transient by defining it like

services.AddDbContext<DbContext>(ServiceLifetime.Transient);

but because I do changes in multiple different services and commit them at once using the SaveChanges() method this solution doesnt work in my case.

Because my code runs in a service, I was doing something like

using (var scope = Services.CreateScope())
{
   var entities = scope.ServiceProvider.GetRequiredService<IReadService>().GetEntities();
   var writeService = scope.ServiceProvider.GetRequiredService<IWriteService>();
   foreach (Entity entity in entities)
   {
       writeService.DoSomething(entity);
   } 
}

to be able to use the service like if it was a simple request. So to solve the issue i just split the single scope into two, one for the query and the other for the write operations like so:

using (var readScope = Services.CreateScope())
using (var writeScope = Services.CreateScope())
{
   var entities = readScope.ServiceProvider.GetRequiredService<IReadService>().GetEntities();
   var writeService = writeScope.ServiceProvider.GetRequiredService<IWriteService>();
   foreach (Entity entity in entities)
   {
       writeService.DoSomething(entity);
   } 
}

Like that, there are effevtively two different instances of the DbContext being used.

Another possible solution would be to make sure, that the read operation has terminated before starting the iteration. That is not very pratical in my case because there could be a lot of results that would all need to be loaded into memory for the operation which I tried to avoid by using a Queryable in the first place.

Reading images in python

If you just want to read an image in Python using the specified libraries only, I will go with matplotlib

In matplotlib :

import matplotlib.image
read_img = matplotlib.image.imread('your_image.png')

pull access denied repository does not exist or may require docker login

Just make sure to write the docker name correctly!

In my case, I wrote (notice the extra 'u'):

FROM ubunutu:16.04

The correct docker name is:

FROM ubuntu:16.04

Still getting warning : Configuration 'compile' is obsolete and has been replaced with 'implementation'

In my case,it is cause by Realm library,after I update it to latest version(5.1.0 so far) of Realm,the problem solved!

Here is the working gradle script:

buildscript {
repositories {
    jcenter()
    google()
}

dependencies {
    classpath 'com.android.tools.build:gradle:3.1.2'
    classpath "io.realm:realm-gradle-plugin:5.1.0"
    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
    classpath 'com.google.gms:google-services:3.2.1'
  }
}

Dart SDK is not configured

It normally happens when you are download projects from the github. normally dark sdk contains inside flutter.

you can solve this issue following these few steps

  1. go to the setting using (Ctrl + Shift + s)
  2. go the the Languages & Framework
  3. go to Dart
  4. Enable Dark support for the project
  5. Change the dark sdk path C:\flutter\bin\cache\dart-sdk
  6. Apply

Angular-Material DateTime Picker Component?

Angular Material 10 now includes a new date range picker.

To use the new date range picker, you can use the mat-date-range-input and mat-date-range-picker components.

Example

HTML

<mat-form-field>
  <mat-label>Enter a date range</mat-label>
  <mat-date-range-input [rangePicker]="picker">
    <input matStartDate matInput placeholder="Start date">
    <input matEndDate matInput placeholder="End date">
  </mat-date-range-input>
  <mat-datepicker-toggle matSuffix [for]="picker"></mat-datepicker-toggle>
  <mat-date-range-picker #picker></mat-date-range-picker>
</mat-form-field>

You can read and learn more about this in their official documentation.

Unfortunately, they still haven't build a timepicker on this release.

Python Pandas - Find difference between two data frames

Perhaps a simpler one-liner, with identical or different column names. Worked even when df2['Name2'] contained duplicate values.

newDf = df1.set_index('Name1')
           .drop(df2['Name2'], errors='ignore')
           .reset_index(drop=False)

You should not use <Link> outside a <Router>

Make it simple:

render(<BrowserRouter><Main /></BrowserRouter>, document.getElementById('root'));

and don't forget: import { BrowserRouter } from "react-router-dom";

Get list of databases from SQL Server

Don't Get confused, Use the below simple query to get all the databases,

select * from sys.databases

If u need only the User defined databases;

select * from sys.databases WHERE name NOT IN ('master', 'tempdb', 'model', 'msdb'); 

Some of the System database names are (resource,distribution,reportservice,reportservicetempdb) just insert it into the query. If u have the above db's in your machine as default.

What is the difference between T(n) and O(n)?

one is Big "O"

one is Big Theta

http://en.wikipedia.org/wiki/Big_O_notation

Big O means your algorithm will execute in no more steps than in given expression(n^2)

Big Omega means your algorithm will execute in no fewer steps than in the given expression(n^2)

When both condition are true for the same expression, you can use the big theta notation....

Stacked Tabs in Bootstrap 3

To get left and right tabs (now also with sideways) support for Bootstrap 3, bootstrap-vertical-tabs component can be used.

https://github.com/dbtek/bootstrap-vertical-tabs

Python: call a function from string name

Why cant we just use eval()?

def install():
    print "In install"

New method

def installWithOptions(var1, var2):
    print "In install with options " + var1 + " " + var2

And then you call the method as below

method_name1 = 'install()'
method_name2 = 'installWithOptions("a","b")'
eval(method_name1)
eval(method_name2)

This gives the output as

In install
In install with options a b

Angular: Cannot find a differ supporting object '[object Object]'

I think that the object you received in your response payload isn't an array. Perhaps the array you want to iterate is contained into an attribute. You should check the structure of the received data...

You could try something like that:

getusers() {
  this.http.get(`https://api.github.com/search/users?q=${this.input1.value}`)
    .map(response => response.json().items) // <------
    .subscribe(
      data => this.users = data,
      error => console.log(error)
    );
}

Edit

Following the Github doc (developer.github.com/v3/search/#search-users), the format of the response is:

{
  "total_count": 12,
  "incomplete_results": false,
  "items": [
    {
      "login": "mojombo",
      "id": 1,
      (...)
      "type": "User",
      "score": 105.47857
    }
  ]
}

So the list of users is contained into the items field and you should use this:

getusers() {
  this.http.get(`https://api.github.com/search/users?q=${this.input1.value}`)
    .map(response => response.json().items) // <------
    .subscribe(
      data => this.users = data,
      error => console.log(error)
    );
}

Remove quotes from a character vector in R

nump function :)

> nump <- function(x) print(formatC(x, format="fg", big.mark=","), quote=FALSE)

correct answer:

x <- 1234567890123456

> nump(x)

[1] 1,234,567,890,123,456 

Custom Drawable for ProgressBar/ProgressDialog

I'm not sure but in this case you can still go with a complete customized AlertDialog by having a seperate layout file set in the alert dialog and set the animation for your imageview using part of your above code that should also do it!

c# datagridview doubleclick on row with FullRowSelect

In CellContentDoubleClick event fires only when double clicking on cell's content. I used this and works:

    private void dgvUserList_CellDoubleClick(object sender, DataGridViewCellEventArgs e)
    {
        MessageBox.Show(e.RowIndex.ToString());
    }

OS detecting makefile

That's the job that GNU's automake/autoconf are designed to solve. You might want to investigate them.

Alternatively you can set environment variables on your different platforms and make you Makefile conditional against them.

Pandas sort by group aggregate and column

Groupby A:

In [0]: grp = df.groupby('A')

Within each group, sum over B and broadcast the values using transform. Then sort by B:

In [1]: grp[['B']].transform(sum).sort('B')
Out[1]:
          B
2 -2.829710
5 -2.829710
1  0.253651
4  0.253651
0  0.551377
3  0.551377

Index the original df by passing the index from above. This will re-order the A values by the aggregate sum of the B values:

In [2]: sort1 = df.ix[grp[['B']].transform(sum).sort('B').index]

In [3]: sort1
Out[3]:
     A         B      C
2  baz -0.528172  False
5  baz -2.301539   True
1  bar -0.611756   True
4  bar  0.865408  False
0  foo  1.624345  False
3  foo -1.072969   True

Finally, sort the 'C' values within groups of 'A' using the sort=False option to preserve the A sort order from step 1:

In [4]: f = lambda x: x.sort('C', ascending=False)

In [5]: sort2 = sort1.groupby('A', sort=False).apply(f)

In [6]: sort2
Out[6]:
         A         B      C
A
baz 5  baz -2.301539   True
    2  baz -0.528172  False
bar 1  bar -0.611756   True
    4  bar  0.865408  False
foo 3  foo -1.072969   True
    0  foo  1.624345  False

Clean up the df index by using reset_index with drop=True:

In [7]: sort2.reset_index(0, drop=True)
Out[7]:
     A         B      C
5  baz -2.301539   True
2  baz -0.528172  False
1  bar -0.611756   True
4  bar  0.865408  False
3  foo -1.072969   True
0  foo  1.624345  False

Cloning specific branch

Please try like this : git clone --single-branch --branch <branchname> <url>

replace <branchname> with your branch and <url> with your url.

url will be like http://[email protected]:portno/yourrepo.git.

Flutter: how to make a TextField with HintText but no Underline?

I was using the TextField flutter control.I got the user typed input using below methods.

onChanged:(value){
}

What is the difference between a definition and a declaration?

There are interesting edge cases in C++ (some of them in C too). Consider

T t;

That can be a definition or a declaration, depending on what type T is:

typedef void T();
T t; // declaration of function "t"

struct X { 
  T t; // declaration of function "t".
};

typedef int T;
T t; // definition of object "t".

In C++, when using templates, there is another edge case.

template <typename T>
struct X { 
  static int member; // declaration
};

template<typename T>
int X<T>::member; // definition

template<>
int X<bool>::member; // declaration!

The last declaration was not a definition. It's the declaration of an explicit specialization of the static member of X<bool>. It tells the compiler: "If it comes to instantiating X<bool>::member, then don't instantiate the definition of the member from the primary template, but use the definition found elsewhere". To make it a definition, you have to supply an initializer

template<>
int X<bool>::member = 1; // definition, belongs into a .cpp file.

Where is Python language used?

Your categorization is not correct:

php, asp and ColdFusion are mostly used for websites, that is correct, but .net is definetly much more than asp you can build desktop applications, too (Paint.NET). I don't know about ColdFusion, but PHP can also be used to write desktop applications.

On the other hand C,C++ are not really often used for web programming, But it can be used for web programming (cgit). Java is definetly a language to develop web applications (spring and much more).

Python is a scripting language like PHP, Perl, Ruby and so much more. It can be used for web programming (django, Zope, Google App Engine, and much more). But it also can be used for desktop applications (Blender 3D, or even for games pygame).

Python can also be translated into binary code like java.

Eclipse executable launcher error: Unable to locate companion shared library

I meet this issue after copy a eclipse installation to another pc.I find the eclipse installation auto created the .p2 directory on my c:\Users\xx.p2, and --launcher.library refer to here.So it doesn't exist on my another pc.
My resolution is to reinstall eclipse:
a)Double click eclipse-inst-win64.exe
b)Click to change to advanced mode.
c)Uncheck the Bundle Pool
d)Finish your installation and copy again.
Everything will work well.

How to dump only specific tables from MySQL?

Usage: mysqldump [OPTIONS] database [tables]

i.e.

mysqldump -u username -p db_name table1_name table2_name table3_name > dump.sql

Extract column values of Dataframe as List in Apache Spark

Below is for Python-

df.select("col_name").rdd.flatMap(lambda x: x).collect()

find all subsets that sum to a particular value

def total_subsets_matching_sum(numbers, sum):
    array = [1] + [0] * (sum)
    for current_number in numbers:
        for num in xrange(sum - current_number, -1, -1):
            if array[num]:
                array[num + current_number] += array[num]
    return array[sum]

assert(total_subsets_matching_sum(range(1, 10), 9)       == 8)
assert(total_subsets_matching_sum({1, 3, 2, 5, 4, 9}, 9) == 4)

Explanation

This is one of the classic problems. The idea is to find the number of possible sums with the current number. And its true that, there is exactly one way to bring sum to 0. At the beginning, we have only one number. We start from our target (variable Maximum in the solution) and subtract that number. If it is possible to get a sum of that number (array element corresponding to that number is not zero) then add it to the array element corresponding to the current number. The program would be easier to understand this way

for current_number in numbers:
    for num in xrange(sum, current_number - 1, -1):
        if array[num - current_number]:
            array[num] += array[num - current_number]

When the number is 1, there is only one way in which you can come up with the sum of 1 (1-1 becomes 0 and the element corresponding to 0 is 1). So the array would be like this (remember element zero will have 1)

[1, 1, 0, 0, 0, 0, 0, 0, 0, 0]

Now, the second number is 2. We start subtracting 2 from 9 and its not valid (since array element of 7 is zero we skip that) we keep doing this till 3. When its 3, 3 - 2 is 1 and the array element corresponding to 1 is 1 and we add it to the array element of 3. and when its 2, 2 - 2 becomes 0 and we the value corresponding to 0 to array element of 2. After this iteration the array looks like this

[1, 1, 1, 1, 0, 0, 0, 0, 0, 0]

We keep doing this till we process all the numbers and the array after every iteration looks like this

[1, 1, 0, 0, 0, 0, 0, 0, 0, 0]
[1, 1, 1, 1, 0, 0, 0, 0, 0, 0]
[1, 1, 1, 2, 1, 1, 1, 0, 0, 0]
[1, 1, 1, 2, 2, 2, 2, 2, 1, 1]
[1, 1, 1, 2, 2, 3, 3, 3, 3, 3]
[1, 1, 1, 2, 2, 3, 4, 4, 4, 5]
[1, 1, 1, 2, 2, 3, 4, 5, 5, 6]
[1, 1, 1, 2, 2, 3, 4, 5, 6, 7]
[1, 1, 1, 2, 2, 3, 4, 5, 6, 8]

After the last iteration, we would have considered all the numbers and the number of ways to get the target would be the array element corresponding to the target value. In our case, Array[9] after the last iteration is 8.

axios post request to send form data

Check out querystring.

You can use it as follows:

var querystring = require('querystring');
axios.post('http://something.com/', querystring.stringify({ foo: 'bar' }));

Move UIView up when the keyboard appears in iOS

Declare a delegate, assign your text field to the delegate and then include these methods.

Assuming you have a login form with email and password text fields, this code will fit perfectly:

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

    [self.emailTextField resignFirstResponder];
    [self.passwordTextField resignFirstResponder];

}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {

    if (self.emailTextField == textField) {
        [self.passwordTextField becomeFirstResponder];
    } else {
        [self.emailTextField resignFirstResponder];
        [self.passwordTextField resignFirstResponder];
    }
    return NO;
}
- (void)viewWillAppear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}

- (void)viewWillDisappear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

#pragma mark - keyboard movements
- (void)keyboardWillShow:(NSNotification *)notification
{
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    [UIView animateWithDuration:0.3 animations:^{
        CGRect f = self.view.frame;
        f.origin.y = -0.5f * keyboardSize.height;
        self.view.frame = f;
    }];
}

-(void)keyboardWillHide:(NSNotification *)notification
{
    [UIView animateWithDuration:0.3 animations:^{
        CGRect f = self.view.frame;
        f.origin.y = 0.0f;
        self.view.frame = f;
    }];
}

How do I send a POST request as a JSON?

In the lastest requests package, you can use json parameter in requests.post() method to send a json dict, and the Content-Type in header will be set to application/json. There is no need to specify header explicitly.

import requests

payload = {'key': 'value'}
requests.post(url, json=payload)

Using Html.ActionLink to call action on different controller

With that parameters you're triggering the wrong overloaded function/method.

What worked for me:

<%= Html.ActionLink("Details", "Details", "Product", new { id=item.ID }, null) %>

It fires HtmlHelper.ActionLink(string linkText, string actionName, string controllerName, object routeValues, object htmlAttributes)

I'm using MVC 4.

Cheerio!

Django Rest Framework File Upload

This is the one of the approach I've applied hopefully it'll help.

     class Model_File_update(APIView):
         parser_classes = (MultiPartParser, FormParser)
         permission_classes = [IsAuthenticated]  # it will check if the user is authenticated or not
         authentication_classes = [JSONWebTokenAuthentication]  # it will authenticate the person by JSON web token

         def put(self, request):
            id = request.GET.get('id')
            obj = Model.objects.get(id=id)
            serializer = Model_Upload_Serializer(obj, data=request.data)
            if serializer.is_valid():
               serializer.save()
               return Response(serializer.data, status=200)
            else:
               return Response(serializer.errors, status=400)

HTML input textbox with a width of 100% overflows table cells

I solved the problem by applying box-sizing:border-box; to the table cells themselves, besides doing the same with the input and the wrapper.

How to get the list of all printers in computer

Look at the static System.Drawing.Printing.PrinterSettings.InstalledPrinters property.

It is a list of the names of all installed printers on the system.

How to send post request to the below post method using postman rest client

The Interface of Postman is changing acccording to the updates.

So You can get full information about postman can get Here.

https://www.getpostman.com/docs/requests

conversion of a varchar data type to a datetime data type resulted in an out-of-range value

But if i take the piece of sql and run it from sql management studio, it will run without issue.

If you are at liberty to, change the service account to your own login, which would inherit your language/regional perferences.

The real crux of the issue is:

I use the following to convert -> date.Value.ToString("MM/dd/yyyy HH:mm:ss")

Please start using parameterized queries so that you won't encounter these issues in the future. It is also more robust, predictable and best practice.

What is the difference between Cygwin and MinGW?

Other answers already hit the target. I just want to add an illustration for a quick catch.

enter image description here

Tab Escape Character?

Easy one! "\t"

Edit: In fact, here's something official: Escape Sequences

How do you create vectors with specific intervals in R?

Use the code

x = seq(0,100,5) #this means (starting number, ending number, interval)

the output will be

[1]   0   5  10  15  20  25  30  35  40  45  50  55  60  65  70  75
[17]  80  85  90  95 100

If Python is interpreted, what are .pyc files?

To speed up loading modules, Python caches the compiled content of modules in .pyc.

CPython compiles its source code into "byte code", and for performance reasons, it caches this byte code on the file system whenever the source file has changes. This makes loading of Python modules much faster because the compilation phase can be bypassed. When your source file is foo.py , CPython caches the byte code in a foo.pyc file right next to the source.

In python3, Python's import machinery is extended to write and search for byte code cache files in a single directory inside every Python package directory. This directory will be called __pycache__ .

Here is a flow chart describing how modules are loaded:

enter image description here

For more information:

ref:PEP3147
ref:“Compiled” Python files

How to format a floating number to fixed width in Python

In Python 3.

GPA = 2.5
print(" %6.1f " % GPA)

6.1f means after the dots 1 digits show if you print 2 digits after the dots you should only %6.2f such that %6.3f 3 digits print after the point.

What are 'get' and 'set' in Swift?

You should look at Computed Properties

In your code sample, perimeter is a property not backed up by a class variable, instead its value is computed using the get method and stored via the set method - usually referred to as getter and setter.

When you use that property like this:

var cp = myClass.perimeter

you are invoking the code contained in the get code block, and when you use it like this:

myClass.perimeter = 5.0

you are invoking the code contained in the set code block, where newValue is automatically filled with the value provided at the right of the assignment operator.

Computed properties can be readwrite if both a getter and a setter are specified, or readonly if the getter only is specified.

How to set tbody height with overflow scroll

Based on this answer, here's a minimal solution if you're already using Bootstrap:

div.scrollable-table-wrapper {
  height: 500px;
  overflow: auto;

  thead tr th {
    position: sticky;
    top: 0;
  }
}
<div class="scrollable-table-wrapper">
  <table class="table">
    <thead>...</thead>
    <tbody>...</tbody>
  </table>
</div>

Tested on Bootstrap v3

Where are static methods and static variables stored in Java?

Class variables(Static variables) are stored as part of the Class object associated with that class. This Class object can only be created by JVM and is stored in permanent generation.

Also some have answered that it is stored in non heap area which is called Method Area. Even this answer is not wrong. It is just a debatable topic whether Permgen Area is a part of heap or not. Obviously perceptions differ from person to person. In my opinion we provide heap space and permgen space differently in JVM arguments. So it is a good assumption to treat them differently.

Another way to see it

Memory pools are created by JVM memory managers during runtime. Memory pool may belong to either heap or non-heap memory.A run time constant pool is a per-class or per-interface run time representation of the constant_pool table in a class file. Each runtime constant pool is allocated from the Java virtual machine’s method area and Static Variables are stored in this Method Area. Also this non-heap is nothing but perm gen area.Actually Method area is part of perm gen.(Reference)

enter image description here

Is it possible to convert char[] to char* in C?

It sounds like you're confused between pointers and arrays. Pointers and arrays (in this case char * and char []) are not the same thing.

  • An array char a[SIZE] says that the value at the location of a is an array of length SIZE
  • A pointer char *a; says that the value at the location of a is a pointer to a char. This can be combined with pointer arithmetic to behave like an array (eg, a[10] is 10 entries past wherever a points)

In memory, it looks like this (example taken from the FAQ):

 char a[] = "hello";  // array

   +---+---+---+---+---+---+
a: | h | e | l | l | o |\0 |
   +---+---+---+---+---+---+

 char *p = "world"; // pointer

   +-----+     +---+---+---+---+---+---+
p: |  *======> | w | o | r | l | d |\0 |
   +-----+     +---+---+---+---+---+---+

It's easy to be confused about the difference between pointers and arrays, because in many cases, an array reference "decays" to a pointer to it's first element. This means that in many cases (such as when passed to a function call) arrays become pointers. If you'd like to know more, this section of the C FAQ describes the differences in detail.

One major practical difference is that the compiler knows how long an array is. Using the examples above:

char a[] = "hello";  
char *p =  "world";  

sizeof(a); // 6 - one byte for each character in the string,
           // one for the '\0' terminator
sizeof(p); // whatever the size of the pointer is
           // probably 4 or 8 on most machines (depending on whether it's a 
           // 32 or 64 bit machine)

Without seeing your code, it's hard to recommend the best course of action, but I suspect changing to use pointers everywhere will solve the problems you're currently having. Take note that now:

  • You will need to initialise memory wherever the arrays used to be. Eg, char a[10]; will become char *a = malloc(10 * sizeof(char));, followed by a check that a != NULL. Note that you don't actually need to say sizeof(char) in this case, because sizeof(char) is defined to be 1. I left it in for completeness.

  • Anywhere you previously had sizeof(a) for array length will need to be replaced by the length of the memory you allocated (if you're using strings, you could use strlen(), which counts up to the '\0').

  • You will need a make a corresponding call to free() for each call to malloc(). This tells the computer you are done using the memory you asked for with malloc(). If your pointer is a, just write free(a); at a point in the code where you know you no longer need whatever a points to.

As another answer pointed out, if you want to get the address of the start of an array, you can use:

char* p = &a[0] 

You can read this as "char pointer p becomes the address of element [0] of a".

Responsive width Facebook Page Plugin

Don't forget the data-href field! For me comments were working without it but were not responsive. And of course data-width='100%'

How to use JavaScript variables in jQuery selectors?

  1. ES6 String Template

    Here is a simple way if you don't need IE/EDGE support

    $(`input[id=${x}]`).hide();
    

    or

    $(`input[id=${$(this).attr("name")}]`).hide();
    

    This is a es6 feature called template string

    _x000D_
    _x000D_
        (function($) {_x000D_
            $("input[type=button]").click(function() {_x000D_
                var x = $(this).attr("name");_x000D_
                $(`input[id=${x}]`).toggle(); //use hide instead of toggle_x000D_
            });_x000D_
        })(jQuery);
    _x000D_
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
        <input type="text" id="bx" />_x000D_
        <input type="button" name="bx" value="1" />_x000D_
        <input type="text" id="by" />_x000D_
        <input type="button" name="by" value="2" />_x000D_
    _x000D_
     
    _x000D_
    _x000D_
    _x000D_


  1. String Concatenation

    If you need IE/EDGE support use

    $("#" + $(this).attr("name")).hide();
    

    _x000D_
    _x000D_
        (function($) {_x000D_
            $("input[type=button]").click(function() {_x000D_
                $("#" + $(this).attr("name")).toggle(); //use hide instead of toggle_x000D_
            });_x000D_
        })(jQuery);
    _x000D_
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
        <input type="text" id="bx" />_x000D_
        <input type="button" name="bx" value="1" />_x000D_
        <input type="text" id="by" />_x000D_
        <input type="button" name="by" value="2" />_x000D_
    _x000D_
     
    _x000D_
    _x000D_
    _x000D_


  1. Selector in DOM as data attribute

    This is my preferred way as it makes you code really DRY

    // HTML
    <input type="text"   id="bx" />
    <input type="button" data-input-sel="#bx" value="1" class="js-hide-onclick"/>
    
    //JS
    $($(this).data("input-sel")).hide();
    

    _x000D_
    _x000D_
        (function($) {_x000D_
            $(".js-hide-onclick").click(function() {_x000D_
                $($(this).data("input-sel")).toggle(); //use hide instead of toggle_x000D_
            });_x000D_
        })(jQuery);
    _x000D_
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
        <input type="text" id="bx" />_x000D_
        <input type="button" data-input-sel="#bx" value="1" class="js-hide-onclick" />_x000D_
        <input type="text" id="by" />_x000D_
        <input type="button" data-input-sel="#by" value="2" class="js-hide-onclick" />_x000D_
    _x000D_
     
    _x000D_
    _x000D_
    _x000D_

VB.net: Date without time

Or, if for some reason you don't like any of the more sensible answers, just discard everything to the right of (and including) the space.

Twitter bootstrap hide element on small devices

<div class="small hidden-xs">
    Some Content Here
</div>

This also works for elements not necessarily used in a grid /small column. When it is rendered on larger screens the font-size will be smaller than your default text font-size.

This answer satisfies the question in the OP title (which is how I found this Q/A).

Lollipop : draw behind statusBar with its color set to transparent

The Right solution is to Change a property in XML under your Activity tag to below style. It just works

  android:theme="@style/Theme.AppCompat.Light.NoActionBar"

Creating/writing into a new file in Qt

#include <QFile>
#include <QCoreApplication>
#include <QTextStream>

int main(int argc, char *argv[])
{
    // Create a new file     
    QFile file("out.txt");
    file.open(QIODevice::WriteOnly | QIODevice::Text);
    QTextStream out(&file);
    out << "This file is generated by Qt\n";

    // optional, as QFile destructor will already do it:
    file.close(); 

    //this would normally start the event loop, but is not needed for this
    //minimal example:
    //return app.exec();

    return 0;
}

How do I force a DIV block to extend to the bottom of a page even if it has no content?

I think the issue would be fixed just making the html fill 100% also, might be body fills the 100% of the html but html doesn't fill 100% of the screen.

Try with:

html, body {
      height: 100%;
}

Python read in string from file and split it into values

>>> [[int(i) for i in line.strip().split(',')] for line in open('input.txt').readlines()]
[[995957, 16833579], [995959, 16777241], [995960, 16829368], [995961, 50431654]]

Change image onmouseover

Here is an example:

HTML code:

<img id="myImg" src="http://static.jquery.com/files/rocker/images/logo_jquery_215x53.gif"/>

JavaScript code:

$(document).ready(function() {
    $( "#myImg" ).mouseover(function(){
        $(this).attr("src", "http://www.jqueryui.com/images/logo.gif");
    });

    $( "#myImg" ).mouseout(function(){
        $(this).attr("src", "http://static.jquery.com/files/rocker/images/logo_jquery_215x53.gif");
    });
});

Edit: Sorry, your code was a bit strange. Now I understood what you were doing. ;) The hover method is better, of course.

Android Studio - UNEXPECTED TOP-LEVEL EXCEPTION:

Like everyone else said here, the support library (com.android.support) is being included more than once in your project. Try adding this in your build.gradle at the root level and it should exclude the support library from being exported via other project dependencies.

configurations {
    all*.exclude group: 'com.android.support', module: 'support-v4'
}

If you have more then one support libs included in the dependencies like this, you may want to remove one of them:enter image description here

Display back button on action bar

This is simple and works for me very well

add this inside onCreate() method

getSupportActionBar().setHomeButtonEnabled(true);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);

add this outside oncreate() method

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    onBackPressed();
    return true;
}

SelectSingleNode returning null for known good xml node path using XPath

Sorry, you forgot the namespace. You need:

XmlNamespaceManager ns = new XmlNamespaceManager(myXmlDoc.NameTable);
ns.AddNamespace("hl7","urn:hl7-org:v3");
XmlNode idNode = myXmlDoc.SelectSingleNode("/My_RootNode/hl7:id", ns);

In fact, whether here or in web services, getting null back from an XPath operation or anything that depends on XPath usually indicates a problem with XML namespaces.

Display JSON Data in HTML Table

There are many plugins for doing that. I normally use datatables it works great. http://datatables.net/

Copying formula to the next row when inserting a new row

You need to insert the new row and then copy from the source row to the newly inserted row. Excel allows you to paste special just formulas. So in Excel:

  • Insert the new row
  • Copy the source row
  • Select the newly created target row, right click and paste special
  • Paste as formulas

VBA if required with Rows("1:1") being source and Rows("2:2") being target:

Rows("2:2").Insert Shift:=xlDown, CopyOrigin:=xlFormatFromLeftOrAbove
Rows("2:2").Clear

Rows("1:1").Copy
Rows("2:2").PasteSpecial Paste:=xlPasteFormulas, Operation:=xlNone

Reading HTML content from a UIWebView

To get the whole HTML raw data (with <head> and <body>):

NSString *html = [webView stringByEvaluatingJavaScriptFromString:@"document.documentElement.outerHTML"];

Can you force Visual Studio to always run as an Administrator in Windows 8?

Visual Studio does elevate itself automatically if the project's application manifest specifies an administrative requestedExecutionLevel, so you just need to edit that. Visual Studio will detect that and relaunch itself as administrator when needed.

How do I add a Font Awesome icon to input field?

Change your input to a button element and you can use the Font Awesome classes on it. The alignment of the glyph isn't great in the demo, but you get the idea:

http://tinker.io/802b6/1

<div id="search-bar">
  <form method="get" action="search.php" autocomplete="off" name="form_search">
    <input type="hidden" name="type" value="videos" />
        <input autocomplete="on" id="keyword" name="keyword" value="Search Videos" onclick="clickclear(this,
        'Search Videos')" onblur="clickrecall(this,'Search Videos')" style="font-family: verdana; font-weight:bold;
        font-size: 10pt; height: 28px; width:186px; color: #000000; padding-left: 2px; border: 1px solid black; background-color:
        #ffffff" /><!--
        --><button class="icon-search">Search</button>
    <div id="searchBoxSuggestions"></div>
    </form>
</div>

#search-bar .icon-search {
    width: 30px;
    height: 30px;
    background: black;
    color: white;
    border: none;
    overflow: hidden;
    vertical-align: middle;
    padding: 0;
}

#search-bar .icon-search:before {
    display: inline-block;
    width: 30px;
    height: 30px;
}

The advantage here is that the form is still fully functional without having to add event handlers for elements that aren't buttons but look like one.

Get JavaScript object from array of objects by value of property

It looks like in the ECMAScript 6 proposal there are the Array methods find() and findIndex(). MDN also offers polyfills which you can include to get the functionality of these across all browsers.

find():

function isPrime(element, index, array) {
    var start = 2;
    while (start <= Math.sqrt(element)) {
        if (element % start++ < 1) return false;
    }
    return (element > 1);
}

console.log( [4, 6, 8, 12].find(isPrime) ); // undefined, not found
console.log( [4, 5, 8, 12].find(isPrime) ); // 5

findIndex():

function isPrime(element, index, array) {
    var start = 2;
    while (start <= Math.sqrt(element)) {
        if (element % start++ < 1) return false;
    }
    return (element > 1);
}

console.log( [4, 6, 8, 12].findIndex(isPrime) ); // -1, not found
console.log( [4, 6, 7, 12].findIndex(isPrime) ); // 2

SQL Server : export query as a .txt file

Another way is from command line, using the osql:

OSQL -S SERVERNAME -E -i thequeryfile.sql -o youroutputfile.txt

This can be used from a BAT file and shceduled by a windows user to authenticated.

Change color of Label in C#

I am going to assume this is a WinForms questions (which it feels like, based on it being a "program" rather than a website/app). In which case you can simple do the following to change the text colour of a label:

myLabel.ForeColor = System.Drawing.Color.Red;

Or any other colour of your choice. If you want to be more specific you can use an RGB value like so:

myLabel.ForeColor = Color.FromArgb(0, 0, 0);//(R, G, B) (0, 0, 0 = black)

Having different colours for different users can be done a number of ways. For example, you could allow each user to specify their own RGB value colours, store these somewhere and then load them when the user "connects".

An alternative method could be to just use 2 colours - 1 for the current user (running the app) and another colour for everyone else. This would help the user quickly identify their own messages above others.

A third approach could be to generate the colour randomly - however you will likely get conflicting values that do not show well against your background, so I would suggest not taking this approach. You could have a pre-defined list of "acceptable" colours and just pop one from that list for each user that joins.

ASP.NET MVC DropDownListFor with model of type List<string>

I realize this question was asked a long time ago, but I came here looking for answers and wasn't satisfied with anything I could find. I finally found the answer here:

https://www.tutorialsteacher.com/mvc/htmlhelper-dropdownlist-dropdownlistfor

To get the results from the form, use the FormCollection and then pull each individual value out by it's model name thus:

yourRecord.FieldName = Request.Form["FieldNameInModel"];

As far as I could tell it makes absolutely no difference what argument name you give to the FormCollection - use Request.Form["NameFromModel"] to retrieve it.

No, I did not dig down to see how th4e magic works under the covers. I just know it works...

I hope this helps somebody avoid the hours I spent trying different approaches before I got it working.

How to pass multiple parameters in thread in VB

First of all: AddressOf just gets the delegate to a function - you cannot specify anything else (i.e. capture any variables).

Now, you can start up a thread in two possible ways.

  • Pass an Action in the constructor and just Start() the thread.
  • Pass a ParameterizedThreadStart and forward one extra object argument to the method pointed to when calling .Start(parameter)

I consider the latter option an anachronism from pre-generic, pre-lambda times - which have ended at the latest with VB10.

You could use that crude method and create a list or structure which you pass to your threading code as this single object parameter, but since we now have closures, you can just create the thread on an anonymous Sub that knows all necessary variables by itself (which is work performed for you by the compiler).

Soo ...

Dim Evaluator = New Thread(Sub() Me.TestThread(goodList, 1))

It's really just that ;)

How to round the minute of a datetime object

yes, if your data belongs to a DateTime column in a pandas series, you can round it up using the built-in pandas.Series.dt.round function. See documentation here on pandas.Series.dt.round. In your case of rounding to 10min it will be Series.dt.round('10min') or Series.dt.round('600s') like so:

pandas.Series(tm).dt.round('10min')

Edit to add Example code:

import datetime
import pandas

tm = datetime.datetime(2010, 6, 10, 3, 56, 23)
tm_rounded = pandas.Series(tm).dt.round('10min')
print(tm_rounded)

>>> 0   2010-06-10 04:00:00
dtype: datetime64[ns]

Get time of specific timezone

This is Correct way to get ##

function getTime(offset)
        {
            var d = new Date();
            localTime = d.getTime();
            localOffset = d.getTimezoneOffset() * 60000;

            // obtain UTC time in msec
            utc = localTime + localOffset;
            // create new Date object for different city
            // using supplied offset
            var nd = new Date(utc + (3600000*offset));
            //nd = 3600000 + nd;
            utc = new Date(utc);
            // return time as a string
            $("#local").html(nd.toLocaleString());
            $("#utc").html(utc.toLocaleString());
        }

Android TextView Justify Text

I found a way to solve this problem, but this may not be very grace, but the effect is not bad.

Its principle is to replace the spaces of each line to the fixed-width ImageSpan (the color is transparent).

public static void justify(final TextView textView) {

    final AtomicBoolean isJustify = new AtomicBoolean(false);

    final String textString = textView.getText().toString();

    final TextPaint textPaint = textView.getPaint();

    final SpannableStringBuilder builder = new SpannableStringBuilder();

    textView.post(new Runnable() {
        @Override
        public void run() {

            if (!isJustify.get()) {

                final int lineCount = textView.getLineCount();
                final int textViewWidth = textView.getWidth();

                for (int i = 0; i < lineCount; i++) {

                    int lineStart = textView.getLayout().getLineStart(i);
                    int lineEnd = textView.getLayout().getLineEnd(i);

                    String lineString = textString.substring(lineStart, lineEnd);

                    if (i == lineCount - 1) {
                        builder.append(new SpannableString(lineString));
                        break;
                    }

                    String trimSpaceText = lineString.trim();
                    String removeSpaceText = lineString.replaceAll(" ", "");

                    float removeSpaceWidth = textPaint.measureText(removeSpaceText);
                    float spaceCount = trimSpaceText.length() - removeSpaceText.length();

                    float eachSpaceWidth = (textViewWidth - removeSpaceWidth) / spaceCount;

                    SpannableString spannableString = new SpannableString(lineString);
                    for (int j = 0; j < trimSpaceText.length(); j++) {
                        char c = trimSpaceText.charAt(j);
                        if (c == ' ') {
                            Drawable drawable = new ColorDrawable(0x00ffffff);
                            drawable.setBounds(0, 0, (int) eachSpaceWidth, 0);
                            ImageSpan span = new ImageSpan(drawable);
                            spannableString.setSpan(span, j, j + 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
                        }
                    }

                    builder.append(spannableString);
                }

                textView.setText(builder);
                isJustify.set(true);
            }
        }
    });
}

I put the code on GitHub: https://github.com/twiceyuan/TextJustification

Overview:

Overview

Default interface methods are only supported starting with Android N

My project use ButterKnife and Retro lambda, setting JavaVersion.VERSION_1_8 will not work. It always blames at ButterKnife static interface function until I found this Migrate from Retrolambda

TL;DR

Just add JavaVersion.VERSION_1_8 and completely REMOVE retrolambda from your project. It will build successfully.

Partial Dependency (Databases)

Partial dependency implies is a situation where a non-prime attribute(An attribute that does not form part of the determinant(Primary key/Candidate key)) is functionally dependent to a portion/part of a primary key/Candidate key.

Add a new line to the end of a JtextArea

When you want to create a new line or wrap in your TextArea you have to add \n (newline) after the text.

TextArea t = new TextArea();
t.setText("insert text when you want a new line add \nThen more text....);
setBounds();
setFont();
add(t);

This is the only way I was able to do it, maybe there is a simpler way but I havent discovered that yet.

Django error - matching query does not exist

your line raising the error is here:

comment = Comment.objects.get(pk=comment_id)

you try to access a non-existing comment.

from django.shortcuts import get_object_or_404

comment = get_object_or_404(Comment, pk=comment_id)

Instead of having an error on your server, your user will get a 404 meaning that he tries to access a non existing resource.

Ok up to here I suppose you are aware of this.

Some users (and I'm part of them) let tabs running for long time, if users are authorized to delete data, it may happens. A 404 error may be a better error to handle a deleted resource error than sending an email to the admin.

Other users go to addresses from their history, (same if data have been deleted since it may happens).

Get scroll position using jquery

cross browser variant

$(document).scrollTop();

MySQL: Quick breakdown of the types of joins

I have 2 tables like this:

> SELECT * FROM table_a;
+------+------+
| id   | name |
+------+------+
|    1 | row1 |
|    2 | row2 |
+------+------+

> SELECT * FROM table_b;
+------+------+------+
| id   | name | aid  |
+------+------+------+
|    3 | row3 |    1 |
|    4 | row4 |    1 |
|    5 | row5 | NULL |
+------+------+------+

INNER JOIN cares about both tables

INNER JOIN cares about both tables, so you only get a row if both tables have one. If there is more than one matching pair, you get multiple rows.

> SELECT * FROM table_a a INNER JOIN table_b b ON a.id=b.aid;
+------+------+------+------+------+
| id   | name | id   | name | aid  |
+------+------+------+------+------+
|    1 | row1 |    3 | row3 | 1    |
|    1 | row1 |    4 | row4 | 1    |
+------+------+------+------+------+

It makes no difference to INNER JOIN if you reverse the order, because it cares about both tables:

> SELECT * FROM table_b b INNER JOIN table_a a ON a.id=b.aid;
+------+------+------+------+------+
| id   | name | aid  | id   | name |
+------+------+------+------+------+
|    3 | row3 | 1    |    1 | row1 |
|    4 | row4 | 1    |    1 | row1 |
+------+------+------+------+------+

You get the same rows, but the columns are in a different order because we mentioned the tables in a different order.

LEFT JOIN only cares about the first table

LEFT JOIN cares about the first table you give it, and doesn't care much about the second, so you always get the rows from the first table, even if there is no corresponding row in the second:

> SELECT * FROM table_a a LEFT JOIN table_b b ON a.id=b.aid;
+------+------+------+------+------+
| id   | name | id   | name | aid  |
+------+------+------+------+------+
|    1 | row1 |    3 | row3 | 1    |
|    1 | row1 |    4 | row4 | 1    |
|    2 | row2 | NULL | NULL | NULL |
+------+------+------+------+------+

Above you can see all rows of table_a even though some of them do not match with anything in table b, but not all rows of table_b - only ones that match something in table_a.

If we reverse the order of the tables, LEFT JOIN behaves differently:

> SELECT * FROM table_b b LEFT JOIN table_a a ON a.id=b.aid;
+------+------+------+------+------+
| id   | name | aid  | id   | name |
+------+------+------+------+------+
|    3 | row3 | 1    |    1 | row1 |
|    4 | row4 | 1    |    1 | row1 |
|    5 | row5 | NULL | NULL | NULL |
+------+------+------+------+------+

Now we get all rows of table_b, but only matching rows of table_a.

RIGHT JOIN only cares about the second table

a RIGHT JOIN b gets you exactly the same rows as b LEFT JOIN a. The only difference is the default order of the columns.

> SELECT * FROM table_a a RIGHT JOIN table_b b ON a.id=b.aid;
+------+------+------+------+------+
| id   | name | id   | name | aid  |
+------+------+------+------+------+
|    1 | row1 |    3 | row3 | 1    |
|    1 | row1 |    4 | row4 | 1    |
| NULL | NULL |    5 | row5 | NULL |
+------+------+------+------+------+

This is the same rows as table_b LEFT JOIN table_a, which we saw in the LEFT JOIN section.

Similarly:

> SELECT * FROM table_b b RIGHT JOIN table_a a ON a.id=b.aid;
+------+------+------+------+------+
| id   | name | aid  | id   | name |
+------+------+------+------+------+
|    3 | row3 | 1    |    1 | row1 |
|    4 | row4 | 1    |    1 | row1 |
| NULL | NULL | NULL |    2 | row2 |
+------+------+------+------+------+

Is the same rows as table_a LEFT JOIN table_b.

No join at all gives you copies of everything

If you write your tables with no JOIN clause at all, just separated by commas, you get every row of the first table written next to every row of the second table, in every possible combination:

> SELECT * FROM table_b b, table_a;
+------+------+------+------+------+
| id   | name | aid  | id   | name |
+------+------+------+------+------+
|    3 | row3 | 1    |    1 | row1 |
|    3 | row3 | 1    |    2 | row2 |
|    4 | row4 | 1    |    1 | row1 |
|    4 | row4 | 1    |    2 | row2 |
|    5 | row5 | NULL |    1 | row1 |
|    5 | row5 | NULL |    2 | row2 |
+------+------+------+------+------+

(This is from my blog post Examples of SQL join types)

Sticky Header after scrolling down

Here is a JS fiddle http://jsfiddle.net/ke9kW/1/

As the others say, set the header to fixed, and start it with display: none

then jQuery

$(window).scroll(function () {
  if ( $(this).scrollTop() > 200 && !$('header').hasClass('open') ) {
    $('header').addClass('open');
    $('header').slideDown();
   } else if ( $(this).scrollTop() <= 200 ) {
    $('header').removeClass('open');
    $('header').slideUp();
  }
});

where 200 is the height in pixels you'd like it to move down at. The addition of the open class is to allow us to run an elseif instead of just else, so some of the code doesn't unnecessarily run on every scrollevent, save a lil bit of memory

Disable XML validation in Eclipse

Ensure your encoding is correct for all of your files, this can sometimes happen if you have the encoding wrong for your file or the wrong encoding in your XML header.

So, if I have the following NewFile.xml:

<?xml version="1.0" encoding="UTF-16"?>
<bar foo="foiré" />

And the eclipse encoding is UTF-8:

Eclipse Encoding Resource

The encoding of your file, the defined encoding in Eclipse (through Properties->Resource) and the declared encoding in the XML document all need to agree.

The validator is attempting to read the file, expecting <?xml ... but because the encoding is different from that expected, it's not finding it. Hence the error: Content is not allowed in prolog. The prolog is the bit before the <?xml declaration.

EDIT: Sorry, didn't realise that the .xml files were generated and actually contain javascript.

When you suspend the validators, the error messages that you've generated don't go away. To get them to go away, you have to manually delete them.

  1. Suspend the validators
  2. Click on the 'Content is not allowed in prolog' message, right click and delete. You can select multiple ones, or all of them.
  3. Do a Project->Clean. The messages should not come back.

I think that because you've suspended the validators, Eclipse doesn't realise it has to delete the old error messages which came from the validators.

Maximum value of maxRequestLength?

These two settings worked for me to upload 1GB mp4 videos.

<system.web>
    <httpRuntime maxRequestLength="2097152" requestLengthDiskThreshold="2097152" executionTimeout="240"/>
</system.web>
<system.webServer>
    <security>
        <requestFiltering>
            <requestLimits maxAllowedContentLength="2147483648" />
        </requestFiltering>
    </security>
</system.webServer>

How to install wkhtmltopdf on a linux based (shared hosting) web server

Shared hosting no ssh or shell access?

Here is how i did it;

  1. Visit https://wkhtmltopdf.org/downloads.html and download the appropriate stable release for Linux. For my case I chose 32-bit which is wkhtmltox-0.12.4_linux-generic-i386.tar.xz
  2. Unzip to a folder on your local drive.
  3. Upload the folder to public_html (or whichever location fits your need) using an FTP program just like any other file(s)
  4. Change the binary paths in snappy.php file to point the appropriate files in the folder you just uploaded. Bingo! there you have it. You should be able to generate PDF files.

Split large string in n-size chunks in JavaScript

Here's a solution I came up with for template strings after a little experimenting:

Usage:

chunkString(5)`testing123`

_x000D_
_x000D_
function chunkString(nSize) {_x000D_
    return (strToChunk) => {_x000D_
        let result = [];_x000D_
        let chars = String(strToChunk).split('');_x000D_
_x000D_
        for(let i = 0; i < (String(strToChunk).length / nSize); i++) {_x000D_
            result = result.concat(chars.slice(i*nSize,(i+1)*nSize).join(''));_x000D_
        }_x000D_
        return result_x000D_
    }_x000D_
}_x000D_
_x000D_
document.write(chunkString(5)`testing123`);_x000D_
// returns: testi,ng123_x000D_
_x000D_
document.write(chunkString(3)`testing123`);_x000D_
// returns: tes,tin,g12,3
_x000D_
_x000D_
_x000D_

Integer division: How do you produce a double?

Best way to do this is

int i = 3;
Double d = i * 1.0;

d is 3.0 now.

How to disable SSL certificate checking with Spring RestTemplate?

@Bean(name = "restTemplateByPassSSL")
public RestTemplate restTemplateByPassSSL()
        throws KeyStoreException, NoSuchAlgorithmException, KeyManagementException {
    TrustStrategy acceptingTrustStrategy = (X509Certificate[] chain, String authType) -> true;
    HostnameVerifier hostnameVerifier = (s, sslSession) -> true;
    SSLContext sslContext = SSLContexts.custom().loadTrustMaterial(null, acceptingTrustStrategy).build();
    SSLConnectionSocketFactory csf = new SSLConnectionSocketFactory(sslContext, hostnameVerifier);
    CloseableHttpClient httpClient = HttpClients.custom().setSSLSocketFactory(csf).build();
    HttpComponentsClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory();
    requestFactory.setHttpClient(httpClient);

    return new RestTemplate(requestFactory);
}

Change URL parameters

URL query parameters can be easily modified using URLSearchParams and History interfaces:

// Construct URLSearchParams object instance from current URL querystring.
var queryParams = new URLSearchParams(window.location.search);
 
// Set new or modify existing parameter value. 
//queryParams.set("myParam", "myValue");
queryParams.set("rows", "10");
 
// Replace current querystring with the new one.
history.replaceState(null, null, "?"+queryParams.toString());

Alternatively instead of modifying current history entry using replaceState() we can use pushState() method to create a new one:

history.pushState(null, null, "?"+queryParams.toString());

https://zgadzaj.com/development/javascript/how-to-change-url-query-parameter-with-javascript-only

Delete all files of specific type (extension) recursively down a directory using a batch file

If you are trying to delete certain .extensions in the C: drive use this cmd:

del /s c:\*.blaawbg

I had a customer that got a encryption virus and i needed to find all junk files and delete them.

Git log out user from command line

Remove your SSH keys from ~/.ssh (or where you stored them).

Remove your user settings:

git config --global --unset user.name
git config --global --unset user.email
git config --global --unset credential.helper

Or all your global settings:

git config --global --unset-all

Maybe there's something else related to the credentials store, but I always used git over SSH.

What is the difference between a cer, pvk, and pfx file?

Here are my personal, super-condensed notes, as far as this subject pertains to me currently, for anyone who's interested:

  • Both PKCS12 and PEM can store entire cert chains: public keys, private keys, and root (CA) certs.
  • .pfx == .p12 == "PKCS12"
    • fully encrypted
  • .pem == .cer == .cert == "PEM" (or maybe not... could be binary... see comments...)
    • base-64 (string) encoded X509 cert (binary) with a header and footer
      • base-64 is basically just a string of "A-Za-z0-9+/" used to represent 0-63, 6 bits of binary at a time, in sequence, sometimes with 1 or 2 "=" characters at the very end when there are leftovers ("=" being "filler/junk/ignore/throw away" characters)
      • the header and footer is something like "-----BEGIN CERTIFICATE-----" and "-----END CERTIFICATE-----" or "-----BEGIN ENCRYPTED PRIVATE KEY-----" and "-----END ENCRYPTED PRIVATE KEY-----"
    • Windows recognizes .cer and .cert as cert files
  • .jks == "Java Key Store"
    • just a Java-specific file format which the API uses
      • .p12 and .pfx files can also be used with the JKS API
  • "Trust Stores" contain public, trusted, root (CA) certs, whereas "Identity/Key Stores" contain private, identity certs; file-wise, however, they are the same.

String comparison technique used by Python

Take a look also at How do I sort unicode strings alphabetically in Python? where the discussion is about sorting rules given by the Unicode Collation Algorithm (http://www.unicode.org/reports/tr10/).

To reply to the comment

What? How else can ordering be defined other than left-to-right?

by S.Lott, there is a famous counter-example when sorting French language. It involves accents: indeed, one could say that, in French, letters are sorted left-to-right and accents right-to-left. Here is the counter-example: we have e < é and o < ô, so you would expect the words cote, coté, côte, côté to be sorted as cote < coté < côte < côté. Well, this is not what happens, in fact you have: cote < côte < coté < côté, i.e., if we remove "c" and "t", we get oe < ôe < oé < ôé, which is exactly right-to-left ordering.

And a last remark: you shouldn't be talking about left-to-right and right-to-left sorting but rather about forward and backward sorting.

Indeed there are languages written from right to left and if you think Arabic and Hebrew are sorted right-to-left you may be right from a graphical point of view, but you are wrong on the logical level!

Indeed, Unicode considers character strings encoded in logical order, and writing direction is a phenomenon occurring on the glyph level. In other words, even if in the word ???? the letter shin appears on the right of the lamed, logically it occurs before it. To sort this word one will first consider the shin, then the lamed, then the vav, then the mem, and this is forward ordering (although Hebrew is written right-to-left), while French accents are sorted backwards (although French is written left-to-right).

How can I disable HREF if onclick is executed?

It's simpler if you pass an event parameter like this:

<a href="#" onclick="yes_js_login(event);">link</a>
function yes_js_login(e) {
    e.stopImmediatePropagation();
}

How do I install Composer on a shared hosting?

SIMPLE SOLUTION (tested on Red Hat):

run command: curl -sS https://getcomposer.org/installer | php

to use it: php composer.phar

SYSTEM WIDE SOLLUTION (tested on Red Hat):

run command: mv composer.phar /usr/local/bin/composer

to use it: composer update

now you can call composer from any directory.

Source: http://www.agix.com.au/install-composer-on-centosredhat/

how to convert string to numerical values in mongodb

Three things need to care for:

  1. parseInt() will store double data type in mongodb. Please use new NumberInt(string).
  2. in Mongo shell command for bulk usage, yield won't work. Please DO NOT add 'yield'.
  3. If you already change string to double by parseInt(). It looks like you have no way to change the type to int directly. The solution is a little bit wired: change double to string first and then change back to int by new NumberInt().

Understanding PrimeFaces process/update and JSF f:ajax execute/render attributes

<p:commandXxx process> <p:ajax process> <f:ajax execute>

The process attribute is server side and can only affect UIComponents implementing EditableValueHolder (input fields) or ActionSource (command fields). The process attribute tells JSF, using a space-separated list of client IDs, which components exactly must be processed through the entire JSF lifecycle upon (partial) form submit.

JSF will then apply the request values (finding HTTP request parameter based on component's own client ID and then either setting it as submitted value in case of EditableValueHolder components or queueing a new ActionEvent in case of ActionSource components), perform conversion, validation and updating the model values (EditableValueHolder components only) and finally invoke the queued ActionEvent (ActionSource components only). JSF will skip processing of all other components which are not covered by process attribute. Also, components whose rendered attribute evaluates to false during apply request values phase will also be skipped as part of safeguard against tampered requests.

Note that it's in case of ActionSource components (such as <p:commandButton>) very important that you also include the component itself in the process attribute, particularly if you intend to invoke the action associated with the component. So the below example which intends to process only certain input component(s) when a certain command component is invoked ain't gonna work:

<p:inputText id="foo" value="#{bean.foo}" />
<p:commandButton process="foo" action="#{bean.action}" />

It would only process the #{bean.foo} and not the #{bean.action}. You'd need to include the command component itself as well:

<p:inputText id="foo" value="#{bean.foo}" />
<p:commandButton process="@this foo" action="#{bean.action}" />

Or, as you apparently found out, using @parent if they happen to be the only components having a common parent:

<p:panel><!-- Type doesn't matter, as long as it's a common parent. -->
    <p:inputText id="foo" value="#{bean.foo}" />
    <p:commandButton process="@parent" action="#{bean.action}" />
</p:panel>

Or, if they both happen to be the only components of the parent UIForm component, then you can also use @form:

<h:form>
    <p:inputText id="foo" value="#{bean.foo}" />
    <p:commandButton process="@form" action="#{bean.action}" />
</h:form>

This is sometimes undesirable if the form contains more input components which you'd like to skip in processing, more than often in cases when you'd like to update another input component(s) or some UI section based on the current input component in an ajax listener method. You namely don't want that validation errors on other input components are preventing the ajax listener method from being executed.

Then there's the @all. This has no special effect in process attribute, but only in update attribute. A process="@all" behaves exactly the same as process="@form". HTML doesn't support submitting multiple forms at once anyway.

There's by the way also a @none which may be useful in case you absolutely don't need to process anything, but only want to update some specific parts via update, particularly those sections whose content doesn't depend on submitted values or action listeners.

Noted should be that the process attribute has no influence on the HTTP request payload (the amount of request parameters). Meaning, the default HTML behavior of sending "everything" contained within the HTML representation of the <h:form> will be not be affected. In case you have a large form, and want to reduce the HTTP request payload to only these absolutely necessary in processing, i.e. only these covered by process attribute, then you can set the partialSubmit attribute in PrimeFaces Ajax components as in <p:commandXxx ... partialSubmit="true"> or <p:ajax ... partialSubmit="true">. You can also configure this 'globally' by editing web.xml and add

<context-param>
    <param-name>primefaces.SUBMIT</param-name>
    <param-value>partial</param-value>
</context-param>

Alternatively, you can also use <o:form> of OmniFaces 3.0+ which defaults to this behavior.

The standard JSF equivalent to the PrimeFaces specific process is execute from <f:ajax execute>. It behaves exactly the same except that it doesn't support a comma-separated string while the PrimeFaces one does (although I personally recommend to just stick to space-separated convention), nor the @parent keyword. Also, it may be useful to know that <p:commandXxx process> defaults to @form while <p:ajax process> and <f:ajax execute> defaults to @this. Finally, it's also useful to know that process supports the so-called "PrimeFaces Selectors", see also How do PrimeFaces Selectors as in update="@(.myClass)" work?


<p:commandXxx update> <p:ajax update> <f:ajax render>

The update attribute is client side and can affect the HTML representation of all UIComponents. The update attribute tells JavaScript (the one responsible for handling the ajax request/response), using a space-separated list of client IDs, which parts in the HTML DOM tree need to be updated as response to the form submit.

JSF will then prepare the right ajax response for that, containing only the requested parts to update. JSF will skip all other components which are not covered by update attribute in the ajax response, hereby keeping the response payload small. Also, components whose rendered attribute evaluates to false during render response phase will be skipped. Note that even though it would return true, JavaScript cannot update it in the HTML DOM tree if it was initially false. You'd need to wrap it or update its parent instead. See also Ajax update/render does not work on a component which has rendered attribute.

Usually, you'd like to update only the components which really need to be "refreshed" in the client side upon (partial) form submit. The example below updates the entire parent form via @form:

<h:form>
    <p:inputText id="foo" value="#{bean.foo}" required="true" />
    <p:message id="foo_m" for="foo" />
    <p:inputText id="bar" value="#{bean.bar}" required="true" />
    <p:message id="bar_m" for="bar" />
    <p:commandButton action="#{bean.action}" update="@form" />
</h:form>

(note that process attribute is omitted as that defaults to @form already)

Whilst that may work fine, the update of input and command components is in this particular example unnecessary. Unless you change the model values foo and bar inside action method (which would in turn be unintuitive in UX perspective), there's no point of updating them. The message components are the only which really need to be updated:

<h:form>
    <p:inputText id="foo" value="#{bean.foo}" required="true" />
    <p:message id="foo_m" for="foo" />
    <p:inputText id="bar" value="#{bean.bar}" required="true" />
    <p:message id="bar_m" for="bar" />
    <p:commandButton action="#{bean.action}" update="foo_m bar_m" />
</h:form>

However, that gets tedious when you have many of them. That's one of the reasons why PrimeFaces Selectors exist. Those message components have in the generated HTML output a common style class of ui-message, so the following should also do:

<h:form>
    <p:inputText id="foo" value="#{bean.foo}" required="true" />
    <p:message id="foo_m" for="foo" />
    <p:inputText id="bar" value="#{bean.bar}" required="true" />
    <p:message id="bar_m" for="bar" />
    <p:commandButton action="#{bean.action}" update="@(.ui-message)" />
</h:form>

(note that you should keep the IDs on message components, otherwise @(...) won't work! Again, see How do PrimeFaces Selectors as in update="@(.myClass)" work? for detail)

The @parent updates only the parent component, which thus covers the current component and all siblings and their children. This is more useful if you have separated the form in sane groups with each its own responsibility. The @this updates, obviously, only the current component. Normally, this is only necessary when you need to change one of the component's own HTML attributes in the action method. E.g.

<p:commandButton action="#{bean.action}" update="@this" 
    oncomplete="doSomething('#{bean.value}')" />

Imagine that the oncomplete needs to work with the value which is changed in action, then this construct wouldn't have worked if the component isn't updated, for the simple reason that oncomplete is part of generated HTML output (and thus all EL expressions in there are evaluated during render response).

The @all updates the entire document, which should be used with care. Normally, you'd like to use a true GET request for this instead by either a plain link (<a> or <h:link>) or a redirect-after-POST by ?faces-redirect=true or ExternalContext#redirect(). In effects, process="@form" update="@all" has exactly the same effect as a non-ajax (non-partial) submit. In my entire JSF career, the only sensible use case I encountered for @all is to display an error page in its entirety in case an exception occurs during an ajax request. See also What is the correct way to deal with JSF 2.0 exceptions for AJAXified components?

The standard JSF equivalent to the PrimeFaces specific update is render from <f:ajax render>. It behaves exactly the same except that it doesn't support a comma-separated string while the PrimeFaces one does (although I personally recommend to just stick to space-separated convention), nor the @parent keyword. Both update and render defaults to @none (which is, "nothing").


See also:

How to add a tooltip to an svg graphic?

On svg, the right way to write the title

<svg>
  <title id="unique-id">Checkout</title>
</svg>

check here for more details https://css-tricks.com/svg-title-vs-html-title-attribute/

How to set initial value and auto increment in MySQL?

MySQL - Setup an auto-incrementing primary key that starts at 1001:

Step 1, create your table:

create table penguins(
  my_id       int(16) auto_increment, 
  skipper     varchar(4000),
  PRIMARY KEY (my_id)
)

Step 2, set the start number for auto increment primary key:

ALTER TABLE penguins AUTO_INCREMENT=1001;

Step 3, insert some rows:

insert into penguins (skipper) values("We need more power!");
insert into penguins (skipper) values("Time to fire up");
insert into penguins (skipper) values("kowalski's nuclear reactor.");

Step 4, interpret the output:

select * from penguins

prints:

'1001', 'We need more power!'
'1002', 'Time to fire up'
'1003', 'kowalski\'s nuclear reactor'

SQL Connection Error: System.Data.SqlClient.SqlException (0x80131904)

Check you routes, the update on 9/28/2014 impacted us. We had to adjust our older servers and add new routes. Here is the article http://www.rackspace.com/knowledge_center/article/updating-servicenet-routes-on-cloud-servers-created-before-june-3-2013

Reading CSV file and storing values into an array

You can use Microsoft.VisualBasic.FileIO.TextFieldParser dll in C# for better performance

get below code example from above article

static void Main()
{
    string csv_file_path=@"C:\Users\Administrator\Desktop\test.csv";

    DataTable csvData = GetDataTabletFromCSVFile(csv_file_path);

    Console.WriteLine("Rows count:" + csvData.Rows.Count);

    Console.ReadLine();
}


private static DataTable GetDataTabletFromCSVFile(string csv_file_path)
{
    DataTable csvData = new DataTable();

    try
    {

    using(TextFieldParser csvReader = new TextFieldParser(csv_file_path))
        {
            csvReader.SetDelimiters(new string[] { "," });
            csvReader.HasFieldsEnclosedInQuotes = true;
            string[] colFields = csvReader.ReadFields();
            foreach (string column in colFields)
            {
                DataColumn datecolumn = new DataColumn(column);
                datecolumn.AllowDBNull = true;
                csvData.Columns.Add(datecolumn);
            }

            while (!csvReader.EndOfData)
            {
                string[] fieldData = csvReader.ReadFields();
                //Making empty value as null
                for (int i = 0; i < fieldData.Length; i++)
                {
                    if (fieldData[i] == "")
                    {
                        fieldData[i] = null;
                    }
                }
                csvData.Rows.Add(fieldData);
            }
        }
    }
    catch (Exception ex)
    {
    }
    return csvData;
}

JavaScript file upload size validation

If you set the Ie 'Document Mode' to 'Standards' you can use the simple javascript 'size' method to get the uploaded file's size.

Set the Ie 'Document Mode' to 'Standards':

<meta http-equiv="X-UA-Compatible" content="IE=Edge">

Than, use the 'size' javascript method to get the uploaded file's size:

<script type="text/javascript">
    var uploadedFile = document.getElementById('imageUpload');
    var fileSize = uploadedFile.files[0].size;
    alert(fileSize); 
</script>

It works for me.

Global variables in AngularJS

Try this, you will not force to inject $rootScope in controller.

app.run(function($rootScope) {
    $rootScope.Currency = 'USD';
});

You can only use it in run block because config block will not provide you to use service of $rootScope.

Can't start Eclipse - Java was started but returned exit code=13

In my case, I have two different JDK that is IBM and Oracle JDK. I moved IBM JDK to the top of the Oracle JDK in environment variable then it worked. Note: I am going to use IBM JDK so I moved up.

javascript, for loop defines a dynamic variable name

You cannot create different "variable names" but you can create different object properties. There are many ways to do whatever it is you're actually trying to accomplish. In your case I would just do

for (var i = myArray.length - 1; i >= 0; i--) {    console.log(eval(myArray[i])); }; 

More generally you can create object properties dynamically, which is the type of flexibility you're thinking of.

var result = {}; for (var i = myArray.length - 1; i >= 0; i--) {     result[myArray[i]] = eval(myArray[i]);   }; 

I'm being a little handwavey since I don't actually understand language theory, but in pure Javascript (including Node) references (i.e. variable names) are happening at a higher level than at runtime. More like at the call stack; you certainly can't manufacture them in your code like you produce objects or arrays. Browsers do actually let you do this anyway though it's terrible practice, via

window['myVarName'] = 'namingCollisionsAreFun';  

(per comment)

In-place type conversion of a NumPy array

import numpy as np
arr_float = np.arange(10, dtype=np.float32)
arr_int = arr_float.view(np.float32)

use view() and parameter 'dtype' to change the array in place.

javascript: using a condition in switch case

You've way overcomplicated that. Write it with if statements instead like this:

if(liCount == 0)
    setLayoutState('start');
else if(liCount<=5)
    setLayoutState('upload1Row');
else if(liCount<=10)
    setLayoutState('upload2Rows');

$('#UploadList').data('jsp').reinitialise();

Or, if ChaosPandion is trying to optimize as much as possible:

setLayoutState(liCount == 0 ? 'start' :
               liCount <= 5 ? 'upload1Row' :
               liCount <= 10 ? 'upload2Rows' :
               null);

$('#UploadList').data('jsp').reinitialise();

how to check for null with a ng-if values in a view with angularjs?

You should check for !test, here is a fiddle showing that.

<span ng-if="!test">null</span>

How do I view the SSIS packages in SQL Server Management Studio?

  1. you could find it under intergration services option in object explorer.
  2. you could find the packages under integration services catalog where all packages are deployed.

How to check if directory exist using C++ and winAPI

0.1 second Google search:

BOOL DirectoryExists(const char* dirName) {
  DWORD attribs = ::GetFileAttributesA(dirName);
  if (attribs == INVALID_FILE_ATTRIBUTES) {
    return false;
  }
  return (attribs & FILE_ATTRIBUTE_DIRECTORY);
}

PHP simple foreach loop with HTML

This will work although when embedding PHP in HTML it is better practice to use the following form:

<table>
    <?php foreach($array as $key=>$value): ?>
    <tr>
        <td><?= $key; ?></td>
    </tr>
    <?php endforeach; ?>
</table>

You can find the doc for the alternative syntax on PHP.net

Access to the path denied error in C#

Did you try specifing some file name?

eg:

string route="D:\\somefilename.txt";

Formatting struct timespec

The following will return an ISO8601 and RFC3339-compliant UTC timestamp, including nanoseconds.

It uses strftime(), which works with struct timespec just as well as with struct timeval because all it cares about is the number of seconds, which both provide. Nanoseconds are then appended (careful to pad with zeros!) as well as the UTC suffix 'Z'.

Example output: 2021-01-19T04:50:01.435561072Z

#include <stdio.h>
#include <time.h>
#include <sys/time.h>

int utc_system_timestamp(char[]);

int main(void) {
    char buf[31];
    utc_system_timestamp(buf);
    printf("%s\n", buf);
}

// Allocate exactly 31 bytes for buf
int utc_system_timestamp(char buf[]) {
        const int bufsize = 31;
        struct timespec now;
        struct tm tm;
        int retval = clock_gettime(CLOCK_REALTIME, &now);
        gmtime_r(&now.tv_sec, &tm);
        strftime(buf, bufsize, "%Y-%m-%dT%H:%M:%S.", &tm);
        sprintf(buf, "%s%09luZ", buf, now.tv_nsec);
        return retval;
}

Emulate Samsung Galaxy Tab

I found under website.

http://developer.samsung.com/android/tools-sdks/Samsung-GALAXY-Tab-Emulator

Extract zip file to add-ons under android sdk path. then launch Android SDK Manager. under "extras" folder check "Android + Google APIs for GALAXY Tab, API 8, revision 1" item and install package.

That's all.

How do I auto size a UIScrollView to fit its content

I added this to Espuz and JCC's answer. It uses the y position of the subviews and doesn't include the scroll bars. Edit Uses the bottom of the lowest sub view that is visible.

+ (CGFloat) bottomOfLowestContent:(UIView*) view
{
    CGFloat lowestPoint = 0.0;

    BOOL restoreHorizontal = NO;
    BOOL restoreVertical = NO;

    if ([view respondsToSelector:@selector(setShowsHorizontalScrollIndicator:)] && [view respondsToSelector:@selector(setShowsVerticalScrollIndicator:)])
    {
        if ([(UIScrollView*)view showsHorizontalScrollIndicator])
        {
            restoreHorizontal = YES;
            [(UIScrollView*)view setShowsHorizontalScrollIndicator:NO];
        }
        if ([(UIScrollView*)view showsVerticalScrollIndicator])
        {
            restoreVertical = YES;
            [(UIScrollView*)view setShowsVerticalScrollIndicator:NO];
        }
    }
    for (UIView *subView in view.subviews)
    {
        if (!subView.hidden)
        {
            CGFloat maxY = CGRectGetMaxY(subView.frame);
            if (maxY > lowestPoint)
            {
                lowestPoint = maxY;
            }
        }
    }
    if ([view respondsToSelector:@selector(setShowsHorizontalScrollIndicator:)] && [view respondsToSelector:@selector(setShowsVerticalScrollIndicator:)])
    {
        if (restoreHorizontal)
        {
            [(UIScrollView*)view setShowsHorizontalScrollIndicator:YES];
        }
        if (restoreVertical)
        {
            [(UIScrollView*)view setShowsVerticalScrollIndicator:YES];
        }
    }

    return lowestPoint;
}

Comparing two files in linux terminal

You can use diff tool in linux to compare two files. You can use --changed-group-format and --unchanged-group-format options to filter required data.

Following three options can use to select the relevant group for each option:

  • '%<' get lines from FILE1

  • '%>' get lines from FILE2

  • '' (empty string) for removing lines from both files.

E.g: diff --changed-group-format="%<" --unchanged-group-format="" file1.txt file2.txt

[root@vmoracle11 tmp]# cat file1.txt 
test one
test two
test three
test four
test eight
[root@vmoracle11 tmp]# cat file2.txt 
test one
test three
test nine
[root@vmoracle11 tmp]# diff --changed-group-format='%<' --unchanged-group-format='' file1.txt file2.txt 
test two
test four
test eight

Best way to format multiple 'or' conditions in an if statement (Java)

No you cannot do that in Java. you can however write a method as follows:

boolean isContains(int i, int ... numbers) {
    // code to check if i is one of the numbers
    for (int n : numbers) {
        if (i == n) return true;
    }
    return false;
}

Remove property for all objects in array

For my opinion this is the simplest variant

array.map(({good}) => ({good}))

How do I create a timer in WPF?

Adding to the above. You use the Dispatch timer if you want the tick events marshalled back to the UI thread. Otherwise I would use System.Timers.Timer.

JSON and escaping characters

This is not a bug in either implementation. There is no requirement to escape U+00B0. To quote the RFC:

2.5. Strings

The representation of strings is similar to conventions used in the C family of programming languages. A string begins and ends with quotation marks. All Unicode characters may be placed within the quotation marks except for the characters that must be escaped: quotation mark, reverse solidus, and the control characters (U+0000 through U+001F).

Any character may be escaped.

Escaping everything inflates the size of the data (all code points can be represented in four or fewer bytes in all Unicode transformation formats; whereas encoding them all makes them six or twelve bytes).

It is more likely that you have a text transcoding bug somewhere in your code and escaping everything in the ASCII subset masks the problem. It is a requirement of the JSON spec that all data use a Unicode encoding.

Iterate through Nested JavaScript Objects

var findObjectByLabel = function(obj, label) 
{
  var foundLabel=null;
  if(obj.label === label)
  { 
    return obj; 
  }

for(var i in obj) 
{
    if(Array.isArray(obj[i])==true)
    {
        for(var j=0;j<obj[i].length;j++)
        {
            foundLabel = findObjectByLabel(obj[i], label);
        }
    }
    else if(typeof(obj[i])  == 'object')
    {
        if(obj.hasOwnProperty(i))
        {           
            foundLabel = findObjectByLabel(obj[i], label);     
        }       
    }

    if(foundLabel) 
    { 
        return foundLabel; 
    }

}

return null;
};

var x = findObjectByLabel(cars, "Sedan");
alert(JSON.stringify(x));

Get the string value from List<String> through loop for display

Use the For-Each loop which came with Java 1.5, and it work on Types which are iterable.

ArrayList<String> data = new ArrayList<String>();
data.add("Vivek");
data.add("Vadodara");
data.add("Engineer");
data.add("Feelance");

for (String s : data){

 System.out.prinln("Data of "+data.indexOf(s)+" "+s);

 }

Start service in Android

Probably you don't have the service in your manifest, or it does not have an <intent-filter> that matches your action. Examining LogCat (via adb logcat, DDMS, or the DDMS perspective in Eclipse) should turn up some warnings that may help.

More likely, you should start the service via:

startService(new Intent(this, UpdaterServiceManager.class));

List all files and directories in a directory + subdirectories

I am afraid, the GetFiles method returns list of files but not the directories. The list in the question prompts me that the result should include the folders as well. If you want more customized list, you may try calling GetFiles and GetDirectories recursively. Try this:

List<string> AllFiles = new List<string>();
void ParsePath(string path)
{
    string[] SubDirs = Directory.GetDirectories(path);
    AllFiles.AddRange(SubDirs);
    AllFiles.AddRange(Directory.GetFiles(path));
    foreach (string subdir in SubDirs)
        ParsePath(subdir);
}

Tip: You can use FileInfo and DirectoryInfo classes if you need to check any specific attribute.

JSON parse error: Can not construct instance of java.time.LocalDate: no String-argument constructor/factory method to deserialize from String value

I have just wrestled with this for 3 hours. I credit the answer from Dherik (Bonus material about AMQP) for bringing me within striking distance of MY answer, YMMV.

I registered the JavaTimeModule in my object mapper in my SpringBootApplication like this:

@Bean
@Primary
public ObjectMapper objectMapper(Jackson2ObjectMapperBuilder builder) {
    ObjectMapper objectMapper = builder.build();
    objectMapper.registerModule(new JavaTimeModule());
    return objectMapper;
}

However my Instants that were coming over the STOMP connection were still not deserialising. Then I realised I had inadvertantly created a MappingJackson2MessageConverter which creates a second ObjectMapper. So I guess the moral of the story is: Are you sure you have adjusted all your ObjectMappers? In my case I replaced the MappingJackson2MessageConverter.objectMapper with the outer version that has the JavaTimeModule registered, and all is well:

@Autowired
ObjectMapper objectMapper;

@Bean
public WebSocketStompClient webSocketStompClient(WebSocketClient webSocketClient,
        StompSessionHandler stompSessionHandler) {
    WebSocketStompClient webSocketStompClient = new WebSocketStompClient(webSocketClient);
    MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
    converter.setObjectMapper(objectMapper);
    webSocketStompClient.setMessageConverter(converter);
    webSocketStompClient.connect("http://localhost:8080/myapp", stompSessionHandler);
    return webSocketStompClient;
}

Java division by zero doesnt throw an ArithmeticException - why?

0.0 is a double literal and this is not considered as absolute zero! No exception because it is considered that the double variable large enough to hold the values representing near infinity!

How to SUM parts of a column which have same text value in different column in the same row

This can be done by using SUMPRODUCT as well. Update the ranges as you see fit

=SUMPRODUCT(($A$2:$A$7=A2)*($B$2:$B$7=B2)*$C$2:$C$7)

A2:A7 = First name range

B2:B7 = Last Name Range

C2:C7 = Numbers Range

This will find all the names with the same first and last name and sum the numbers in your numbers column

MySQL SELECT only not null values

SELECT * FROM TABLE_NAME
where COLUMN_NAME <> '';

Change image source with JavaScript

Hi i tried to integrate with your code.

Can you have a look at this?

Thanks M.S

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
_x000D_
<!--TODO: need to integrate this code into the project to change images added 05/21/2016:-->_x000D_
_x000D_
<script type="text/javascript">_x000D_
    function changeImage(a) {_x000D_
        document.getElementById("img").src=a;_x000D_
    }_x000D_
</script>_x000D_
_x000D_
_x000D_
 _x000D_
<title> Fluid Selection </title>_x000D_
<!-- css -->_x000D_
 <link rel="stylesheet" href="bootstrap-3/css/bootstrap.min.css">_x000D_
 <link rel="stylesheet" href="css/main.css">_x000D_
<!-- end css -->_x000D_
<!-- Java script files -->_x000D_
<!-- Date.js date os javascript helper -->_x000D_
    <script src="js/date.js"> </script>_x000D_
_x000D_
<!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->_x000D_
 <script src="js/jquery-2.1.1.min.js"></script>_x000D_
_x000D_
<!-- Include all compiled plugins (below), or include individual files as needed -->_x000D_
 <script src="bootstrap-3/js/bootstrap.min.js"> </script>_x000D_
 <script src="js/library.js"> </script>_x000D_
 <script src="js/sfds.js"> </script>_x000D_
 <script src="js/main.js"> </script>_x000D_
_x000D_
<!-- End Java script files -->_x000D_
_x000D_
<!--added on 05/28/2016-->_x000D_
_x000D_
<style>_x000D_
/* The Modal (background) */_x000D_
.modal {_x000D_
    display: none; /* Hidden by default */_x000D_
    position: fixed; /* Stay in place */_x000D_
    z-index:40001; /* High z-index to ensure it appears above all content */ _x000D_
    padding-top: 100px; /* Location of the box */_x000D_
    left: 0;_x000D_
    top: 0;_x000D_
    width: 100%; /* Full width */_x000D_
    height: 100%; /* Full height */_x000D_
    overflow: auto; /* Enable scroll if needed */_x000D_
   _x000D_
    background-color: rgba(0,0,0,0.9); /* Black w/ opacity */_x000D_
}_x000D_
_x000D_
/* Modal Content */_x000D_
.modal-content {_x000D_
    position: relative;_x000D_
    background-color: #fefefe;_x000D_
    margin: auto;_x000D_
    padding: 0;_x000D_
    border: 1px solid #888;_x000D_
    width: 40%;_x000D_
    box-shadow: 0 4px 8px 0 rgba(0,0,0,0.2),0 6px 20px 0 rgba(0,0,0,0.19);_x000D_
    -webkit-animation-name: animatetop;_x000D_
    -webkit-animation-duration: 0.4s;_x000D_
    animation-name: animatetop;_x000D_
    animation-duration: 0.4s_x000D_
 opacity:.5; /* Sets opacity so it's partly transparent */ -ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)"; _x000D_
 /* IE     _x000D_
 transparency */ filter:alpha(opacity=50); /* More IE transparency */ z-index:40001; } _x000D_
}_x000D_
_x000D_
/* Add Animation */_x000D_
@-webkit-keyframes animatetop {_x000D_
    from {top:-300px; opacity:0} _x000D_
    to {top:0; opacity:1}_x000D_
}_x000D_
_x000D_
@keyframes animatetop {_x000D_
    from {top:-300px; opacity:0}_x000D_
    to {top:0; opacity:1}_x000D_
}_x000D_
_x000D_
/* The Close Button */_x000D_
.close {_x000D_
    _x000D_
}_x000D_
_x000D_
.close:hover,_x000D_
.close:focus {_x000D_
    color: #000;_x000D_
    text-decoration: none;_x000D_
    cursor:pointer;_x000D_
}_x000D_
_x000D_
/* The Close Button */_x000D_
.close2 {_x000D_
    _x000D_
}_x000D_
_x000D_
_x000D_
.close2:focus {_x000D_
    color: #000;_x000D_
    text-decoration: none;_x000D_
    cursor:pointer;_x000D_
}_x000D_
_x000D_
.modal-header {_x000D_
 color: #000;_x000D_
    padding: 2px 16px;_x000D_
 }_x000D_
_x000D_
.modal-body {padding: 2px 16px;}_x000D_
 _x000D_
 _x000D_
}_x000D_
_x000D_
.modal-footer {_x000D_
    padding: 2px 16px;_x000D_
    background-color: #000099;_x000D_
    color: white;_x000D_
}_x000D_
_x000D_
_x000D_
</style>_x000D_
_x000D_
<script>_x000D_
 $(document).ready(function() {_x000D_
 _x000D_
 _x000D_
  $("#water").click(function(event){_x000D_
   var $this= $(this);_x000D_
   if($this.hasClass('clicked')){_x000D_
    $this.removeClass('clicked');_x000D_
    SFDS.setFluidType(0);_x000D_
    $this.find('h3').text('Select the H20 Fluid Type');_x000D_
    }else{_x000D_
     SFDS.setFluidType(1);_x000D_
     $this.addClass('clicked');_x000D_
     $this.find('h3').text('H20 Selected');_x000D_
_x000D_
   }_x000D_
  });_x000D_
  _x000D_
  $("#saline").click(function(event){_x000D_
   var $this= $(this);_x000D_
   if($this.hasClass('clicked')){_x000D_
    $this.removeClass('clicked');_x000D_
    SFDS.setFluidType(0);_x000D_
    $this.find('h3').text('Select the NaCL Fluid Type');_x000D_
    }else{_x000D_
     SFDS.setFluidType(1);_x000D_
     $this.addClass('clicked');_x000D_
     $this.find('h3').text('NaCL Selected');_x000D_
     _x000D_
  _x000D_
  _x000D_
   }_x000D_
  });_x000D_
  _x000D_
 });_x000D_
</script>_x000D_
</head>_x000D_
<body>_x000D_
<div class="container-fluid">_x000D_
 <header>_x000D_
  <div class="row">_x000D_
   <div class="col-xs-6">_x000D_
    <div id="date"><span class="date_time"></span></div>_x000D_
   </div>_x000D_
   <div class="col-xs-6">_x000D_
    <div id="time" class="text-right"><span class="date_time"></span></div>_x000D_
   </div>_x000D_
  </div>_x000D_
 </header>_x000D_
_x000D_
 <div class="row">_x000D_
  <div class="col-md-offset-1 col-sm-3 col-xs-8 col-xs-offset-2 col-sm-offset-0">_x000D_
   <div id="fluid" class="main_button center-block">_x000D_
    <div class="large_circle_button, main_img"> _x000D_
     <h2>Select<br>Fluid</h2>_x000D_
     <img class="center-block large_button_image" src="images/dropwater.png" alt=""/> _x000D_
    </div>_x000D_
    <h1></h1>_x000D_
   </div>_x000D_
  </div>_x000D_
  <div class=" col-md-6 col-sm-offset-1 col-sm-8 col-xs-12">_x000D_
   <div class="row">_x000D_
    <div class="col-xs-12">_x000D_
     <div id="water" class="large_rectangle_button">_x000D_
      <div class="label_wrapper">_x000D_
       <h3>Sterile<br>Water</h3>_x000D_
      </div>_x000D_
      <div id="thumb_img" class="image_wrapper">_x000D_
       <img src="images/dropsterilewater.png" alt="Sterile Water" class="sterile_water_image" onclick='changeImage("images/dropsterilewater.png");'>_x000D_
      </div>_x000D_
      <img src="images/checkmark.png" class="button_checkmark" width="96" height="88">_x000D_
     </div>_x000D_
    </div>_x000D_
    <div class="col-xs-12">_x000D_
     <div id="saline" class="large_rectangle_button">_x000D_
      <div class="label_wrapper">_x000D_
       <h3>Sterile<br>0.9% NaCL</h3>_x000D_
      </div>_x000D_
      <div class="image_wrapper">_x000D_
       <img src="images/cansterilesaline.png" alt= "Sterile Saline" class="sterile_salt_image" onclick='changeImage("images/imagecansterilesaline.png");'>_x000D_
      </div>_x000D_
      <img src="images/checkmark.png" class="button_checkmark" width="96" height="88">_x000D_
_x000D_
     </div>_x000D_
    </div>_x000D_
    <div class="col-xs-12">_x000D_
     <div class="small_rectangle_button">_x000D_
      _x000D_
      <!-- Trigger/Open The Modal -->_x000D_
      <div id="myBtn" class="label_wrapper">_x000D_
       <h3>Change<br>Cartridge</h3>_x000D_
      </div>_x000D_
      <div class="image_wrapper">_x000D_
       <img src="images/changecartridge.png" alt="" class="change_cartrige_image" />_x000D_
      </div>_x000D_
     </div>_x000D_
    </div>_x000D_
    _x000D_
     <!-- The Modal -->_x000D_
     <div id="myModal" class="modal">_x000D_
_x000D_
       <!-- Modal content -->_x000D_
       <div class="modal-content">_x000D_
      <div class="modal-header">_x000D_
        <span class="close"><img src="images/x-icon.png"></span>_x000D_
        <h2>Change Cartridge Instructions</h2>_x000D_
      </div>_x000D_
      <div class="modal-body">_x000D_
        <h4>Lorem ipsum dolor sit amet, dicant nonumes volutpat cu eum, in nulla molestie vim, nec probo option iracundia ut. Tale inermis scripserit ne cum, his no errem minimum commune, usu accumsan omnesque in. Eu has nihil dolor debitis, ad nobis impedit per. Dicat mnesarchum quo at, debet abhorreant consectetuer sea te, postea adversarium et eos. At alii dicit his, liber tantas suscipit sea in, id pri erat probatus. Vel nostro periculis dissentiet te, ut ubique noster vix. Id honestatis disputationi vel, ne vix assum constituam.</h4>                                                   _x000D_
                           <a href="#"><img src="images/video-icon.png" alt="click here for video"> </a>_x000D_
                           <a href="#close2" title="Close" class="close2"><img src="images/cancel-icon.png" alt="Cancel"></a>_x000D_
_x000D_
                          _x000D_
      </div>_x000D_
      <div class="modal-footer">_x000D_
        <h4></h4>_x000D_
      </div>_x000D_
       </div>_x000D_
_x000D_
     </div>_x000D_
     _x000D_
     <!--for comparison-->_x000D_
_x000D_
_x000D_
     _x000D_
_x000D_
     _x000D_
     <script>_x000D_
     // Get the modal_x000D_
     var modal = document.getElementById('myModal');_x000D_
_x000D_
     // Get the button that opens the modal_x000D_
     var btn = document.getElementById("myBtn");_x000D_
_x000D_
     // Get the <span> element that closes the modal_x000D_
     var span = document.getElementsByClassName("close")[0];_x000D_
     _x000D_
_x000D_
     // When the user clicks the button, open the modal _x000D_
     btn.onclick = function() {_x000D_
      modal.style.display = "block";_x000D_
     }_x000D_
_x000D_
     // When the user clicks on <span> (x), close the modal_x000D_
     span.onclick = function() {_x000D_
      modal.style.display = "none";_x000D_
     }_x000D_
_x000D_
     // When the user clicks anywhere outside of the modal, close it_x000D_
     window.onclick = function(event) {_x000D_
      if (event.target == modal) {_x000D_
       modal.style.display = "none";_x000D_
      }_x000D_
      _x000D_
      _x000D_
     }_x000D_
     </script>_x000D_
                    _x000D_
_x000D_
    _x000D_
    _x000D_
    _x000D_
    _x000D_
    _x000D_
   </div>_x000D_
  </div>_x000D_
 </div>_x000D_
</div>_x000D_
<footer class="footer navbar-fixed-bottom">_x000D_
 <div class="container-fluid">_x000D_
  <div class="row cols-bottom">_x000D_
   <div class="col-sm-3">_x000D_
    <a href="main.html">_x000D_
    <div class="small_circle_button">     _x000D_
     <img src="images/buttonback.png" alt="back to home" class="settings"/> <!--  width="49" height="48" -->_x000D_
    </div>_x000D_
   </div></a><div class=" col-sm-6">_x000D_
    <div id="stop_button" >_x000D_
     <img src="images/stop.png" alt="stop" class="center-block stop_button" /> <!-- width="140" height="128" -->_x000D_
    </div>_x000D_
     _x000D_
   </div><div class="col-sm-3">_x000D_
    <div id="parker" class="pull-right">_x000D_
     <img src="images/parkerlogo.png" alt="parkerlogo" /> <!-- width="131" height="65" -->_x000D_
    </div>_x000D_
   </div>_x000D_
  </div>_x000D_
 </div>_x000D_
</footer>_x000D_
_x000D_
_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

How to get the exact local time of client?

Here is a version that works well in September 2020 using fetch and https://worldtimeapi.org/api

_x000D_
_x000D_
fetch("https://worldtimeapi.org/api/ip")
  .then(response => response.json())
  .then(data => console.log(data.dst,data.datetime));
_x000D_
_x000D_
_x000D_

What is the SQL command to return the field names of a table?

This is also MySQL Specific:

show fields from [tablename];

this doesnt just show the table names but it also pulls out all the info about the fields.

Can I add and remove elements of enumeration at runtime in Java

I faced this problem on the formative project of my young career.

The approach I took was to save the values and the names of the enumeration externally, and the end goal was to be able to write code that looked as close to a language enum as possible.

I wanted my solution to look like this:

enum HatType
{
    BASEBALL,
    BRIMLESS,
    INDIANA_JONES
}

HatType mine = HatType.BASEBALL;

// prints "BASEBALL"
System.out.println(mine.toString());

// prints true
System.out.println(mine.equals(HatType.BASEBALL));

And I ended up with something like this:

// in a file somewhere:
// 1 --> BASEBALL
// 2 --> BRIMLESS
// 3 --> INDIANA_JONES

HatDynamicEnum hats = HatEnumRepository.retrieve();

HatEnumValue mine = hats.valueOf("BASEBALL");

// prints "BASEBALL"
System.out.println(mine.toString());

// prints true
System.out.println(mine.equals(hats.valueOf("BASEBALL"));

Since my requirements were that it had to be possible to add members to the enum at run-time, I also implemented that functionality:

hats.addEnum("BATTING_PRACTICE");

HatEnumRepository.storeEnum(hats);

hats = HatEnumRepository.retrieve();

HatEnumValue justArrived = hats.valueOf("BATTING_PRACTICE");
// file now reads:
// 1 --> BASEBALL
// 2 --> BRIMLESS
// 3 --> INDIANA_JONES
// 4 --> BATTING_PRACTICE

I dubbed it the Dynamic Enumeration "pattern", and you read about the original design and its revised edition.

The difference between the two is that the revised edition was designed after I really started to grok OO and DDD. The first one I designed when I was still writing nominally procedural DDD, under time pressure no less.

Having services in React application

I also came from Angular.js area and the services and factories in React.js are more simple.

You can use plain functions or classes, callback style and event Mobx like me :)

_x000D_
_x000D_
// Here we have Service class > dont forget that in JS class is Function_x000D_
class HttpService {_x000D_
  constructor() {_x000D_
    this.data = "Hello data from HttpService";_x000D_
    this.getData = this.getData.bind(this);_x000D_
  }_x000D_
_x000D_
  getData() {_x000D_
    return this.data;_x000D_
  }_x000D_
}_x000D_
_x000D_
_x000D_
// Making Instance of class > it's object now_x000D_
const http = new HttpService();_x000D_
_x000D_
_x000D_
// Here is React Class extended By React_x000D_
class ReactApp extends React.Component {_x000D_
  state = {_x000D_
    data: ""_x000D_
  };_x000D_
_x000D_
  componentDidMount() {_x000D_
    const data = http.getData();_x000D_
_x000D_
    this.setState({_x000D_
      data: data_x000D_
    });_x000D_
  }_x000D_
_x000D_
  render() {_x000D_
    return <div>{this.state.data}</div>;_x000D_
  }_x000D_
}_x000D_
_x000D_
ReactDOM.render(<ReactApp />, document.getElementById("root"));
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
  <meta charset="utf-8">_x000D_
  <meta name="viewport" content="width=device-width">_x000D_
  <title>JS Bin</title>_x000D_
</head>_x000D_
<body>_x000D_
  _x000D_
  <div id="root"></div>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>_x000D_
_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Here is simple example :

How to check not in array element

you can check using php in_array() built in function

<?php
  $os = array("Mac", "NT", "Irix", "Linux");
  if (in_array("Irix", $os)) {
    echo "Got Irix";
 }
 if (in_array("mac", $os)) {
  echo "Got mac";
}
?>

and you can also check using this

<?php
  $search_array = array('first' => 1, 'second' => 4);
  if (array_key_exists('first', $search_array)) {
    echo "The 'first' element is in the array";
   }
   ?>

in_array() is fine if you're only checking but if you need to check that a value exists and return the associated key, array_search is a better option.

$data = array(
0 => 'Key1',
1 => 'Key2'
);

$key = array_search('Key2', $data);

if ($key) {
 echo 'Key is ' . $key;
} else {
 echo 'Key not found';
}

for more details http://php.net/manual/en/function.in-array.php

Where is the visual studio HTML Designer?

Go to [Tools, Options], section "Web Forms Designer" and enable the option "Enable Web Forms Designer". That should give you the Design and Split option again.

Using multiple IF statements in a batch file

Batch files have really very limited logic powers so the best you can hope to come up with is a good workaround that indirectly achieves what you want. That's not to say that you should feel they are inferior to a real language - they still demand the same attention to detail and manual debugging as a real application. It's just that you'll need to work a lot harder to make them do what you want in a robust manner.

For the OP's question it sounds like you require two specific files to exist. Just use a tally:

IF EXIST somefile.txt (
    set /a file1_status=1
)

IF EXIST someotehrfile.txt (
    set /a file2_status=1
)

set /a file_status_result=file1_status + file2_status

if %file_status_result% equ 2 (
    goto somefileexists
)

goto exit

:somefileexists
IF EXIST someotherfile.txt SET var=...

:exit

My example uses 3 variables, but you could just add 1 to file_result_status if the file exists. But if you want more granular control later in your batch file you can record the result for each file as I have done so you don't have to keep checking if a file exists later on.

How to find all occurrences of a substring?

Here's a (very inefficient) way to get all (i.e. even overlapping) matches:

>>> string = "test test test test"
>>> [i for i in range(len(string)) if string.startswith('test', i)]
[0, 5, 10, 15]

Python PDF library

The two that come to mind are:

What's the best way of scraping data from a website?

Yes you can do it yourself. It is just a matter of grabbing the sources of the page and parsing them the way you want.

There are various possibilities. A good combo is using python-requests (built on top of urllib2, it is urllib.request in Python3) and BeautifulSoup4, which has its methods to select elements and also permits CSS selectors:

import requests
from BeautifulSoup4 import BeautifulSoup as bs
request = requests.get("http://foo.bar")
soup = bs(request.text) 
some_elements = soup.find_all("div", class_="myCssClass")

Some will prefer xpath parsing or jquery-like pyquery, lxml or something else.

When the data you want is produced by some JavaScript, the above won't work. You either need python-ghost or Selenium. I prefer the latter combined with PhantomJS, much lighter and simpler to install, and easy to use:

from selenium import webdriver
client = webdriver.PhantomJS()
client.get("http://foo")
soup = bs(client.page_source)

I would advice to start your own solution. You'll understand Scrapy's benefits doing so.

ps: take a look at scrapely: https://github.com/scrapy/scrapely

pps: take a look at Portia, to start extracting information visually, without programming knowledge: https://github.com/scrapinghub/portia

failed to load ad : 3

W/Ads: Failed to load ad: 3

Means: The ad request was successful, but no ad was returned due to lack of ad inventory.

So, In my case, I have commented the keywords: property to load all types of ads. Now my ad is loading properly.

static final MobileAdTargetingInfo targetingInfo = MobileAdTargetingInfo(
        testDevices: testDevice != null ? <String>[testDevice] : null,
        nonPersonalizedAds: true,
        //keywords: <String>['Fitness', 'Yoga', 'Health', 'Exercise', 'Game', 'Doctor', 'Medical'],);

What's the difference between git clone --mirror and git clone --bare

I add a picture, show configdifference between mirror and bare. enter image description here The left is bare, right is mirror. You can be clear, mirror's config file have fetch key, which means you can update it,by git remote update or git fetch --all

macro run-time error '9': subscript out of range

"Subscript out of range" indicates that you've tried to access an element from a collection that doesn't exist. Is there a "Sheet1" in your workbook? If not, you'll need to change that to the name of the worksheet you want to protect.

How to expire a cookie in 30 minutes using jQuery?

If you're using jQuery Cookie (https://plugins.jquery.com/cookie/), you can use decimal point or fractions.

As one day is 1, one minute would be 1 / 1440 (there's 1440 minutes in a day).

So 30 minutes is 30 / 1440 = 0.02083333.

Final code:

$.cookie("example", "foo", { expires: 30 / 1440, path: '/' });

I've added path: '/' so that you don't forget that the cookie is set on the current path. If you're on /my-directory/ the cookie is only set for this very directory.

Best IDE for HTML5, Javascript, CSS, Jquery support with GUI building tools

As per my personal experience Adobe edge is the best tool for HTML5. It's still in preview mode but you will download it free from Adobe site.

AngularJS performs an OPTIONS HTTP request for a cross-origin resource

Perfectly described in pkozlowski's comment. I had working solution with AngularJS 1.2.6 and ASP.NET Web Api but when I had upgraded AngularJS to 1.3.3 then requests failed.

  • Solution for Web Api server was to add handling of the OPTIONS requests at the beginning of configuration method (more info in this blog post):

    app.Use(async (context, next) =>
    {
        IOwinRequest req = context.Request;
        IOwinResponse res = context.Response;
        if (req.Path.StartsWithSegments(new PathString("/Token")))
        {
            var origin = req.Headers.Get("Origin");
            if (!string.IsNullOrEmpty(origin))
            {
                res.Headers.Set("Access-Control-Allow-Origin", origin);
            }
            if (req.Method == "OPTIONS")
            {
                res.StatusCode = 200;
                res.Headers.AppendCommaSeparatedValues("Access-Control-Allow-Methods", "GET", "POST");
                res.Headers.AppendCommaSeparatedValues("Access-Control-Allow-Headers", "authorization", "content-type");
                return;
            }
        }
        await next();
    });
    

Fastest way to get the first object from a queryset in django?

You should use django methods, like exists. Its there for you to use it.

if qs.exists():
    return qs[0]
return None

How do you add a timed delay to a C++ program?

The top answer here seems to be an OS dependent answer; for a more portable solution you can write up a quick sleep function using the ctime header file (although this may be a poor implementation on my part).

#include <iostream>
#include <ctime>

using namespace std;

void sleep(float seconds){
    clock_t startClock = clock();
    float secondsAhead = seconds * CLOCKS_PER_SEC;
    // do nothing until the elapsed time has passed.
    while(clock() < startClock+secondsAhead);
    return;
}
int main(){

    cout << "Next string coming up in one second!" << endl;
    sleep(1.0);
    cout << "Hey, what did I miss?" << endl;

    return 0;
}

Best way to create unique token in Rails?

I think token should be handled just like password. As such, they should be encrypted in DB.

I'n doing something like this to generate a unique new token for a model:

key = ActiveSupport::KeyGenerator
                .new(Devise.secret_key)
                .generate_key("put some random or the name of the key")

loop do
  raw = SecureRandom.urlsafe_base64(nil, false)
  enc = OpenSSL::HMAC.hexdigest('SHA256', key, raw)

  break [raw, enc] unless Model.exist?(token: enc)
end

Best way to define private methods for a class in Objective-C

While I am no Objective-C expert, I personally just define the method in the implementation of my class. Granted, it must be defined before (above) any methods calling it, but it definitely takes the least amount of work to do.

Java constructor/method with optional parameters?

You can simulate it with using varargs, however then you should check it for too many arguments.

public void foo(int param1, int ... param2)
{
   int param2_
   if(param2.length == 0)
      param2_ = 2
   else if(para2.length == 1)
      param2_ = param2[0]
   else
      throw new TooManyArgumentsException(); // user provided too many arguments,

   // rest of the code
}

However this approach is not a good way of doing this, therefore it is better to use overloading.

How can I stop the browser back button using JavaScript?

Some of the solutions here will not prevent a back event from occurring - they let a back event happen (and data held about the page in the browsers memory is lost) and then they play a forward event to try and hide the fact that a back event just happened. Which is unsuccessful if the page held transient state.

I wrote this solution for React (when react router is not being used), which is based on vrfvr's answer.

It will truly stop the back button from doing anything unless the user confirms a popup:

  const onHashChange = useCallback(() => {
    const confirm = window.confirm(
      'Warning - going back will cause you to loose unsaved data. Really go back?',
    );
    window.removeEventListener('hashchange', onHashChange);
    if (confirm) {
      setTimeout(() => {
        window.history.go(-1);
      }, 1);
    } else {
      window.location.hash = 'no-back';
      setTimeout(() => {
        window.addEventListener('hashchange', onHashChange);
      }, 1);
    }
  }, []);

  useEffect(() => {
    window.location.hash = 'no-back';
    setTimeout(() => {
      window.addEventListener('hashchange', onHashChange);
    }, 1);
    return () => {
      window.removeEventListener('hashchange', onHashChange);
    };
  }, []);

Is there a way to specify how many characters of a string to print out using printf()?

The basic way is:

printf ("Here are the first 8 chars: %.8s\n", "A string that is more than 8 chars");

The other, often more useful, way is:

printf ("Here are the first %d chars: %.*s\n", 8, 8, "A string that is more than 8 chars");

Here, you specify the length as an int argument to printf(), which treats the '*' in the format as a request to get the length from an argument.

You can also use the notation:

printf ("Here are the first 8 chars: %*.*s\n",
        8, 8, "A string that is more than 8 chars");

This is also analogous to the "%8.8s" notation, but again allows you to specify the minimum and maximum lengths at runtime - more realistically in a scenario like:

printf("Data: %*.*s Other info: %d\n", minlen, maxlen, string, info);

The POSIX specification for printf() defines these mechanisms.

How do I call an Angular 2 pipe with multiple arguments?

You're missing the actual pipe.

{{ myData | date:'fullDate' }}

Multiple parameters can be separated by a colon (:).

{{ myData | myPipe:'arg1':'arg2':'arg3' }}

Also you can chain pipes, like so:

{{ myData | date:'fullDate' | myPipe:'arg1':'arg2':'arg3' }}

Test only if variable is not null in if statement

I don't believe the expression is sensical as it is.

Elvis means "if truthy, use the value, else use this other thing."

Your "other thing" is a closure, and the value is status != null, neither of which would seem to be what you want. If status is null, Elvis says true. If it's not, you get an extra layer of closure.

Why can't you just use:

(it.description == desc) && ((status == null) || (it.status == status))

Even if that didn't work, all you need is the closure to return the appropriate value, right? There's no need to create two separate find calls, just use an intermediate variable.

Dismissing a Presented View Controller

You can Close your super view window

self.view.superview?.window?.close()

How to test whether a service is running from the command line

SERVICO.BAT
@echo off
echo Servico: %1
if "%1"=="" goto erro
sc query %1 | findstr RUNNING
if %ERRORLEVEL% == 2 goto trouble
if %ERRORLEVEL% == 1 goto stopped
if %ERRORLEVEL% == 0 goto started
echo unknown status
goto end
:trouble
echo trouble
goto end
:started
echo started
goto end
:stopped
echo stopped
goto end
:erro
echo sintaxe: servico NOMESERVICO
goto end

:end

Why write <script type="text/javascript"> when the mime type is set by the server?

Because, at least in HTML 4.01 and XHTML 1(.1), the type attribute for <script> elements is required.

In HTML 5, type is no longer required.

In fact, while you should use text/javascript in your HTML source, many servers will send the file with Content-type: application/javascript. Read more about these MIME types in RFC 4329.

Notice the difference between RFC 4329, that marked text/javascript as obsolete and recommending the use of application/javascript, and the reality in which some browsers freak out on <script> elements containing type="application/javascript" (in HTML source, not the HTTP Content-type header of the file that gets send). Recently, there was a discussion on the WHATWG mailing list about this discrepancy (HTML 5's type defaults to text/javascript), read these messages with subject Will you consider about RFC 4329?

Illegal Escape Character "\"

You can use:

\\

That's ok, for example:

if (invName.substring(j,k).equals("\\")) {
    copyf=invName.substring(0,j);
}

javax.mail.MessagingException: Could not connect to SMTP host: localhost, port: 25

This should not happen. Can you try doing this? Use the system properties and set the property as below:

Properties properties = System.getProperties();
// Setup mail server
properties.setProperty("mail.smtp.host", "10.101.3.229");

And if you have a port associated, then set this as well.

properties.setProperty("mail.smtp.port", "8080");

How do I use 'git reset --hard HEAD' to revert to a previous commit?

WARNING: git clean -f will remove untracked files, meaning they're gone for good since they aren't stored in the repository. Make sure you really want to remove all untracked files before doing this.


Try this and see git clean -f.

git reset --hard will not remove untracked files, where as git-clean will remove any files from the tracked root directory that are not under Git tracking.

Alternatively, as @Paul Betts said, you can do this (beware though - that removes all ignored files too)

  • git clean -df
  • git clean -xdf CAUTION! This will also delete ignored files

What is the effect of extern "C" in C++?

A function void f() compiled by a C compiler and a function with the same name void f() compiled by a C++ compiler are not the same function. If you wrote that function in C, and then you tried to call it from C++, then the linker would look for the C++ function and not find the C function.

extern "C" tells the C++ compiler that you have a function which was compiled by the C compiler. Once you tell it that it was compiled by the C compiler, the C++ compiler will know how to call it correctly.

It also allows the C++ compiler to compile a C++ function in such a way that the C compiler can call it. That function would officially be a C function, but since it is compiled by the C++ compiler, it can use all the C++ features and has all the C++ keywords.

Reading an integer from user input

Better way is to use TryParse:

Int32 _userInput;
if(Int32.TryParse (Console.Readline(), out _userInput) {// do the stuff on userInput}

Entity Framework : How do you refresh the model when the db changes?

I just had to update an .edmx model. The model/Run Custom Tool option was not refreshing the fields for me, but once I had the graphical designer open, I was able to manually rename the fields.

How to check if a char is equal to an empty space?

Character.isSpaceChar(c) || Character.isWhitespace(c) worked for me.

Can someone explain the dollar sign in Javascript?

When using jQuery, the usage of $ symbol as a prefix in the variable name is merely by convention; it is completely optional and serves only to indicate that the variable holds a jQuery object, as in your example.

This means that when another jQuery function needs to be called on the object, you wouldn't need to wrap it in $() again. For instance, compare these:

// the usual way
var item = $(this).parent().parent().find('input');
$(item).hide(); // this is a double wrap, but required for code readability
item.hide(); // this works but is very unclear how a jQuery function is getting called on this 

// with $ prefix
var $item = $(this).parent().parent().find('input');
$item.hide(); // direct call is clear
$($item).hide(); // this works too, but isn't necessary

With the $ prefix the variables already holding jQuery objects are instantly recognizable and the code more readable, and eliminates double/multiple wrapping with $().

How do I setup the InternetExplorerDriver so it works

This is just to help somebody in future. When we initiate InternetExplorerDriver() instance in a java project it uses IEDriver.exe (downloaded by individuals) which tries to extract temporary files in user's TEMP folder when it's not in path then ur busted.

Safest way is to provide your own extract path as shown below

System.setProperty("webdriver.ie.driver.extractpath", "F:\\Study\\");
System.setProperty("webdriver.ie.driver", "F:\\Study\\IEDriverServer.exe");
System.setProperty("webdriver.ie.logfile", "F:\\Study\\IEDriverServer.log");
InternetExplorerDriver d = new InternetExplorerDriver();
d.get("http://www.google.com");
d.quit();

How to use ADB in Android Studio to view an SQLite DB

The issue you are having is common and not explained well in the documentation. Normal devices do not include the sqlite3 database binary which is why you are getting an error. the Android Emeulator, OSX, Linux (if installed) and Windows (after installed) have the binary so you can open a database locally on your machine.

The workaround is to copy the Database from your device to your local machine. This can be accomplished with ADB but requires a number of steps.

Before you start you will need some information:

  • path of the SDK (if not included in your OS environment)
  • your <package name>, for example, com.example.application
  • a <local path> to place your database, eg. ~/Desktop or %userprofile%\Desktop

Next you will need to understand what terminal each command gets written to the first character in the examples below does not get typed but lets you know what shell we are in:

  • > = you OS command prompt
  • $ = ADB shell command Prompt
  • ! = ADB shell as admin command prompt
  • %

Next enter the following commands from Terminal or Command (don't enter first character or text in ())

> adb shell
$ su
! cp /data/data/<package name>/Databases/<database name> /sdcard
! exit
$ exit
> adb pull /sdcard/<database name> <local path>
> sqlite3 <local db path>
% .dump
% .exit  (to exit sqldb)

This is a really round about way of copying the database to your local machine and locally reading the database. There are SO and other resources explaining how to install the sqlite3 binary onto your device from an emulator but for one time access this process works.

If you need to access the database interactively I would suggest running your app in an emulator (that already had sqlite3) or installing sqlite onto your devices /xbin path.

Generate pdf from HTML in div using Javascript

if you need to downloadable pdf of a specific page just add button like this

<h4 onclick="window.print();"> Print </h4>

use window.print() to print your all page not just a div

Hidden features of Python

to activate the autocompletion in IDE that accepts it (like IDLE, Editra, IEP) instead of making: "hi". (and then you hit TAB), you can cheat in the IDE, just make hi". (and you heat TAB) (as you can see, there is no single quote in the beginning) because it will only follows the latest punctuation, it's like when you add : and hit enter, it adds directly an indentation, dont know if it will make change, but it's a tip no more :)

EntityType has no key defined error

The Model class should be changed to :

using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations.Schema;
using System.ComponentModel.DataAnnotations;

namespace MvcApplication1.Models
{
    [Table("studentdetails")]
    public class student
    {
        [Key]
        public int RollNo { get; set; }

        public string Name { get; set; }

        public string Stream { get; set; }

        public string Div { get; set; }
    }
}

Entity Framework vs LINQ to SQL

I think if you need to develop something quick with no Strange things in the middle, and you need the facility to have entities representing your tables:

Linq2Sql can be a good allied, using it with LinQ unleashes a great developing timing.

What is a postback?

Postback refers to HTML forms. An HTML form has 2 methods: GET and POST. These methods determine how data is sent from the client via the form, to the server. A Postback is the action of POSTing back to the submitting page. In essence, it forms a complete circuit from the client, to the server, and back again.

Frontend tool to manage H2 database

I haven't used it, but RazorSQL looks pretty good.

Bootstrap table without stripe / borders

Since Bootstrap v4.1 you can add table-borderless to your table, see official documentation:

<table class='table table-borderless'>

What does the 'export' command do?

In simple terms, environment variables are set when you open a new shell session. At any time if you change any of the variable values, the shell has no way of picking that change. that means the changes you made become effective in new shell sessions. The export command, on the other hand, provides the ability to update the current shell session about the change you made to the exported variable. You don't have to wait until new shell session to use the value of the variable you changed.

JavaScript - document.getElementByID with onClick

window.onload = prepareButton;

function prepareButton()
{ 
   document.getElementById('foo').onclick = function()
   {
       alert('you clicked me');
   }
}

<input id="foo" value="Click Me!" type="button" />

How to save username and password with Mercurial?

While it may or may not work in your situation, I have found it useful to generate a public / private key using Putty's Pageant.

If you are also working with bitbucket (.org) it should give you the ability to provide a public key to your user account and then commands that reach out to the repository will be secured automatically.

If Pageant doesn't start up for you upon a reboot, you can add a shortcut to Pageant to your Windows "Start menu" and the shortcut may need to have a 'properties' populated with the location of your private (.ppk) file.

With this in place Mercurial and your local repositories will need to be set up to push/pull using the SSH format.

Here are some detailed instructions on Atlassian's site for Windows OR Mac/Linux.

You don't have to take my word for it and there are no doubt other ways to do it. Perhaps these steps described here are more for you:

  1. Start PuttyGen from Start -> PuTTY-> PuttyGen
  2. Generate a new key and save it as a .ppk file without a passphrase
  3. Use Putty to login to the server you want to connect to
  4. Append the Public Key text from PuttyGen to the text of ~/.ssh/authorized_keys
  5. Create a shortcut to your .ppk file from Start -> Putty to Start -> Startup
  6. Select the .ppk shortcut from the Startup menu (this will happen automatically at every startup)
  7. See the Pageant icon in the system tray? Right-click it and select “New session”
  8. Enter username@hostname in the “Host name” field
  9. You will now log in automatically.

Is background-color:none valid CSS?

CSS Level 3 specifies the unset property value. From MDN:

The unset CSS keyword is the combination of the initial and inherit keywords. Like these two other CSS-wide keywords, it can be applied to any CSS property, including the CSS shorthand all. This keyword resets the property to its inherited value if it inherits from its parent or to its initial value if not. In other words, it behaves like the inherit keyword in the first case and like the initial keyword in the second case.

Unfortunately this value is currently not supported in all browsers, including IE, Safari and Opera. I suggest using transparent for the time being.

How, in general, does Node.js handle 10,000 concurrent requests?

What you seem to be thinking is that most of the processing is handled in the node event loop. Node actually farms off the I/O work to threads. I/O operations typically take orders of magnitude longer than CPU operations so why have the CPU wait for that? Besides, the OS can handle I/O tasks very well already. In fact, because Node does not wait around it achieves much higher CPU utilisation.

By way of analogy, think of NodeJS as a waiter taking the customer orders while the I/O chefs prepare them in the kitchen. Other systems have multiple chefs, who take a customers order, prepare the meal, clear the table and only then attend to the next customer.

How to import popper.js?

add popper**.js** as dependency instead of popper (only): see the difference in bold.

yarn add popper.js , instead of yarn add popper

it makes the difference.

and include the script according your needs:

as html or the library access as a dependency in SPA applications like react or angular

ReactJS lifecycle method inside a function Component

According to the documentation:

import React, { useState, useEffect } from 'react'
// Similar to componentDidMount and componentDidUpdate:

useEffect(() => {


});

see React documentation

"ImportError: no module named 'requests'" after installing with pip

Opening CMD in the location of the already installed request folder and running "pip install requests" worked for me. I am using two different versions of Python.

I think this works because requests is now installed outside my virtual environment. Haven't checked but just thought I'd write this in, in case anyone else is going crazy searching on Google.

Why is my toFixed() function not working?

Example simple (worked):

var a=Number.parseFloat($("#budget_project").val()); // from input field
var b=Number.parseFloat(html); // from ajax
var c=a-b;
$("#result").html(c.toFixed(2)); // put to id='result' (div or others)

Why split the <script> tag when writing it with document.write()?

I think is for prevent the browser's HTML parser from interpreting the <script>, and mainly the </script> as the closing tag of the actual script, however I don't think that using document.write is a excellent idea for evaluating script blocks, why don't use the DOM...

var newScript = document.createElement("script");
...

How to define relative paths in Visual Studio Project?

Instead of using relative paths, you could also use the predefined macros of VS to achieve this.

$(ProjectDir) points to the directory of your .vcproj file, $(SolutionDir) is the directory of the .sln file.

You get a list of available macros when opening a project, go to
Properties → Configuration Properties → C/C++ → General
and hit the three dots:

project properties

In the upcoming dialog, hit Macros to see the macros that are predefined by the Studio (consult MSDN for their meaning):

additional include directories

You can use the Macros by typing $(MACRO_NAME) (note the $ and the round brackets).

SQL GROUP BY CASE statement with aggregate function

While Shannon's answer is technically correct, it looks like overkill.

The simple solution is that you need to put your summation outside of the case statement. This should do the trick:

sum(CASE WHEN col1 > col2 THEN col3*col4 ELSE 0 END) AS some_product

Basically, your old code tells SQL to execute the sum(X*Y) for each line individually (leaving each line with its own answer that can't be grouped).

The code line I have written takes the sum product, which is what you want.

"CSV file does not exist" for a filename with embedded quotes

What works for me is

dataset = pd.read_csv('FBI_CRIME11.csv')

Highlight it and press enter. It also depends on the IDE you are using. I am using Anaconda Spyder or Jupiter.

PHP: HTTP or HTTPS?

If the request was sent with HTTPS you will have a extra parameter in the $_SERVER superglobal - $_SERVER['HTTPS']. You can check if it is set or not

if( isset($_SERVER['HTTPS'] ) ) {

How to prevent Right Click option using jquery

<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script> 
<script>
 $(document).ready(function(){
  $(document).bind("contextmenu",function(e){
  return false;
  });
});
</script>
</head>
<body>

<p>Right click is disabled on this page.</p>

</body>
</html>

Get the week start date and week end date from week number

This is my solution


    SET DATEFIRST 1;    /* change to use a different datefirst  */
    DECLARE @date DATETIME
    SET @date = CAST('2/6/2019' as date)

    SELECT  DATEADD(dd,0 - (DATEPART(dw, @date) - 1) ,@date) [dateFrom], 
            DATEADD(dd,6 - (DATEPART(dw, @date) - 1) ,@date) [dateTo]

Java Synchronized list

Yes, it will work fine as you have synchronized the list . I would suggest you to use CopyOnWriteArrayList.

CopyOnWriteArrayList<String> cpList=new CopyOnWriteArrayList<String>(new ArrayList<String>());

    void remove(String item)
    {
         do something; (doesn't work on the list)
                 cpList..remove(item);
    }

Send text to specific contact programmatically (whatsapp)

Check this answer. Here your number start with "91**********".

Intent sendIntent = new Intent("android.intent.action.MAIN");
sendIntent.setAction(Intent.ACTION_SEND);

sendIntent.setType("text/plain");                    
sendIntent.putExtra(Intent.EXTRA_TEXT, "This is my text to send.");                   sendIntent.putExtra("jid",PhoneNumberUtils.stripSeparators("91**********")                   + "@s.whatsapp.net");                    
sendIntent.setPackage("com.whatsapp");                    
startActivity(sendIntent);

How to use PrimeFaces p:fileUpload? Listener method is never invoked or UploadedFile is null / throws an error / not usable

I had same issue with primefaces 5.3 and I went through all the points described by BalusC with no result. I followed his advice of debugging FileUploadRenderer#decode() and I discovered that my web.xml was unproperly set

<context-param>
  <param-name>primefaces.UPLOADER</param-name>
  <param-value>auto|native|commons</param-value>
</context-param>

The param-value must be 1 of these 3 values but not all of them!! The whole context-param section can be removed and the default will be auto

How to get the Android Emulator's IP address?

Within the code of my app I can get the running device IP andress easily like beolow:

WifiManager wm = (WifiManager) getSystemService(WIFI_SERVICE);
String ip = Formatter.formatIpAddress(wm.getConnectionInfo().getIpAddress());

Python Error: unsupported operand type(s) for +: 'int' and 'NoneType'

When none of the if test in number_translator() evaluate to true, the function returns None. The error message is the consequence of that.

Whenever you see an error that include 'NoneType' that means that you have an operand or an object that is None when you were expecting something else.

How do I print a double value with full precision using cout?

By full precision, I assume mean enough precision to show the best approximation to the intended value, but it should be pointed out that double is stored using base 2 representation and base 2 can't represent something as trivial as 1.1 exactly. The only way to get the full-full precision of the actual double (with NO ROUND OFF ERROR) is to print out the binary bits (or hex nybbles).

One way of doing that is using a union to type-pun the double to a integer and then printing the integer, since integers do not suffer from truncation or round-off issues. (Type punning like this is not supported by the C++ standard, but it is supported in C. However, most C++ compilers will probably print out the correct value anyways. I think g++ supports this.)

union {
    double d;
    uint64_t u64;
} x;
x.d = 1.1;
std::cout << std::hex << x.u64;

This will give you the 100% accurate precision of the double... and be utterly unreadable because humans can't read IEEE double format ! Wikipedia has a good write up on how to interpret the binary bits.

In newer C++, you can do

std::cout << std::hexfloat << 1.1;

How to run test methods in specific order in JUnit4?

Not sure I agree, If I want to test 'File Upload' and then test 'Data Inserted by File Upload' why would I not want these to be independent from each other? Perfectly reasonable I think to be able to run them separately rather than having both in a Goliath test case.

Get bottom and right position of an element

Vanilla Javascript Answer

var c = document.getElementById("myElement").getBoundingClientRect();
var bot = c.bottom;
var rgt = c.right;

To be clear the element can be anything so long as you have allocated an id to it <img> <div> <p> etc.

for example

<img
    id='myElement'
    src='/img/logout.png'
    className='logoutImg img-button'
    alt='Logout'
/>

How to make certain text not selectable with CSS

Use a simple background image for the textarea suffice.

Or

<div onselectstart="return false">your text</div>

Changing the sign of a number in PHP?

How about something trivial like:

  • inverting:

    $num = -$num;
    
  • converting only positive into negative:

    if ($num > 0) $num = -$num;
    
  • converting only negative into positive:

    if ($num < 0) $num = -$num;
    

What is perm space?

Perm space is used to keep informations for loaded classes and few other advanced features like String Pool(for highly optimized string equality testing), which usually get created by String.intern() methods. As your application(number of classes) will grow this space shall get filled quickly, since the garbage collection on this Space is not much effective to clean up as required, you quickly get Out of Memory : perm gen space error. After then, no application shall run on that machine effectively even after having a huge empty JVM.

Before starting your application you should java -XX:MaxPermSize to get rid of this error.

The HTTP request is unauthorized with client authentication scheme 'Ntlm'

I had to move domain, username, password from

client.ClientCredentials.UserName.UserName = domain + "\\" + username; client.ClientCredentials.UserName.Password = password

to

client.ClientCredentials.Windows.ClientCredential.UserName = username; client.ClientCredentials.Windows.ClientCredential.Password = password; client.ClientCredentials.Windows.ClientCredential.Domain = domain;

How to access single elements in a table in R

Maybe not so perfect as above ones, but I guess this is what you were looking for.

data[1:1,3:3]    #works with positive integers
data[1:1, -3:-3] #does not work, gives the entire 1st row without the 3rd element
data[i:i,j:j]    #given that i and j are positive integers

Here indexing will work from 1, i.e,

data[1:1,1:1]    #means the top-leftmost element

Get Client Machine Name in PHP

In opposite to the most comments, I think it is possible to get the client's hostname (machine name) in plain PHP, but it's a little bit "dirty".

By requesting "NTLM" authorization via HTTP header...

if (!isset($headers['AUTHORIZATION']) || substr($headers['AUTHORIZATION'],0,4) !== 'NTLM'){
    header('HTTP/1.1 401 Unauthorized');
    header('WWW-Authenticate: NTLM');
    exit;
}

You can force the client to send authorization credentials via NTLM format. The NTLM hash sent by the client to server contains, besides the login credtials, the clients machine name. This works cross-browser and PHP only.

$auth = $headers['AUTHORIZATION'];

if (substr($auth,0,5) == 'NTLM ') {
    $msg = base64_decode(substr($auth, 5));
    if (substr($msg, 0, 8) != "NTLMSSPx00")
            die('error header not recognised');

    if ($msg[8] == "x01") {
            $msg2 = "NTLMSSPx00x02"."x00x00x00x00".
                    "x00x00x00x00".
                    "x01x02x81x01".
                    "x00x00x00x00x00x00x00x00".
                    "x00x00x00x00x00x00x00x00".
                    "x00x00x00x00x30x00x00x00";

            header('HTTP/1.1 401 Unauthorized');
            header('WWW-Authenticate: NTLM '.trim(base64_encode($msg2)));
            exit;
    }
    else if ($msg[8] == "x03") {
            function get_msg_str($msg, $start, $unicode = true) {
                    $len = (ord($msg[$start+1]) * 256) + ord($msg[$start]);
                    $off = (ord($msg[$start+5]) * 256) + ord($msg[$start+4]);
                    if ($unicode)
                            return str_replace("\0", '', substr($msg, $off, $len));
                    else
                            return substr($msg, $off, $len);
            }
            $user = get_msg_str($msg, 36);
            $domain = get_msg_str($msg, 28);
            $workstation = get_msg_str($msg, 44);
            print "You are $user from $workstation.$domain";
    }
}

And yes, it's not a plain and easy "read the machine name function", because the user is prompted with an dialog, but it's an example, that it is indeed possible (against the other statements here).

Full code can be found here: https://en.code-bude.net/2017/05/07/how-to-read-client-hostname-in-php/

How to catch SQLServer timeout exceptions

When a client sends ABORT, no transactions are rolled back. To avoid this behavior we have to use SET_XACT_ABORT ON https://docs.microsoft.com/en-us/sql/t-sql/statements/set-xact-abort-transact-sql?view=sql-server-ver15

How can I find an element by CSS class with XPath?

Match against one class that has whitespace.

<div class="hello "></div>
//div[normalize-space(@class)="hello"]

How to get row index number in R?

See row in ?base::row. This gives the row indices for any matrix-like object.

How to sum the values of a JavaScript object?

It can be as simple as that:

const sumValues = obj => Object.values(obj).reduce((a, b) => a + b);

Quoting MDN:

The Object.values() method returns an array of a given object's own enumerable property values, in the same order as that provided by a for...in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well).

from Object.values() on MDN

The reduce() method applies a function against an accumulator and each value of the array (from left-to-right) to reduce it to a single value.

from Array.prototype.reduce() on MDN

You can use this function like that:

sumValues({a: 4, b: 6, c: -5, d: 0}); // gives 5

Note that this code uses some ECMAScript features which are not supported by some older browsers (like IE). You might need to use Babel to compile your code.

Add element to a list In Scala

You are using an immutable list. The operations on the List return a new List. The old List remains unchanged. This can be very useful if another class / method holds a reference to the original collection and is relying on it remaining unchanged. You can either use different named vals as in

val myList1 = 1.0 :: 5.5 :: Nil 
val myList2 = 2.2 :: 3.7 :: mylist1

or use a var as in

var myList = 1.0 :: 5.5 :: Nil 
myList :::= List(2.2, 3.7)

This is equivalent syntax for:

myList = myList.:::(List(2.2, 3.7))

Or you could use one of the mutable collections such as

val myList = scala.collection.mutable.MutableList(1.0, 5.5)
myList.++=(List(2.2, 3.7))

Not to be confused with the following that does not modify the original mutable List, but returns a new value:

myList.++:(List(2.2, 3.7))

However you should only use mutable collections in performance critical code. Immutable collections are much easier to reason about and use. One big advantage is that immutable List and scala.collection.immutable.Vector are Covariant. Don't worry if that doesn't mean anything to you yet. The advantage of it is you can use it without fully understanding it. Hence the collection you were using by default is actually scala.collection.immutable.List its just imported for you automatically.

I tend to use List as my default collection. From 2.12.6 Seq defaults to immutable Seq prior to this it defaulted to immutable.

How to get a certain element in a list, given the position?

Not very efficient, but if you must use a list, you can deference the iterator

*myList.begin()+N

Pandas: how to change all the values of a column?

You can do a column transformation by using apply

Define a clean function to remove the dollar and commas and convert your data to float.

def clean(x):
    x = x.replace("$", "").replace(",", "").replace(" ", "")
    return float(x)

Next, call it on your column like this.

data['Revenue'] = data['Revenue'].apply(clean)