Programs & Examples On #Childwindow

How to append in a json file in Python?

You need to update the output of json.load with a_dict and then dump the result. And you cannot append to the file but you need to overwrite it.

Check whether an array is empty

I can't replicate that (php 5.3.6):

php > $error = array();
php > $error['something'] = false;
php > $error['somethingelse'] = false;
php > var_dump(empty($error));
bool(false)

php > $error = array();
php > var_dump(empty($error));
bool(true)
php >

exactly where are you doing the empty() call that returns true?

Calling a Javascript Function from Console

If it's inside a closure, i'm pretty sure you can't.

Otherwise you just do functionName(); and hit return.

Writelines writes lines without newline, Just fills the file

As we have well established here, writelines does not append the newlines for you. But, what everyone seems to be missing, is that it doesn't have to when used as a direct "counterpart" for readlines() and the initial read persevered the newlines!

When you open a file for reading in binary mode (via 'rb'), then use readlines() to fetch the file contents into memory, split by line, the newlines remain attached to the end of your lines! So, if you then subsequently write them back, you don't likely want writelines to append anything!

So if, you do something like:

with open('test.txt','rb') as f: lines=f.readlines()
with open('test.txt','wb') as f: f.writelines(lines)

You should end up with the same file content you started with.

Style bottom Line in Android

it is completely transparent Edittext with transparent background.

<item>
    <shape android:shape="rectangle" >
        <solid android:color="@color/transparent" />
    </shape>
</item>

<item android:top="-3dp" android:right="-3dp" android:left="-3dp">
    <shape>
        <solid android:color="@android:color/transparent" />
        <stroke

            android:width="2dp"
            android:color="@color/bottomline" />
    </shape>
</item>

Using Oracle to_date function for date string with milliseconds

You can try this format SS.FF for milliseconds:

to_timestamp(table_1.date_col,'DD-Mon-RR HH24:MI:SS.FF')

For more details:
https://docs.oracle.com/cd/B19306_01/server.102/b14200/functions193.htm

How can I center <ul> <li> into div

Steps :

  1. Write style="text-align:center;" to parent div of ul
  2. Write style="display:inline-table;" to ul
  3. Write style="display:inline;" to li

or use

<div class="menu">
 <ul>
   <li>item 1 </li>
   <li>item 2 </li>
   <li>item 3 </li>
 </ul>
</div>

<style>
 .menu { text-align: center; }
 .menu ul { display:inline-table; }
 .menu li { display:inline; }
</style>

In Rails, how do you render JSON using a view?

RABL is probably the nicest solution to this that I've seen if you're looking for a cleaner alternative to ERb syntax. json_builder and argonaut, which are other solutions, both seem somewhat outdated and won't work with Rails 3.1 without some patching.

RABL is available via a gem or check out the GitHub repository; good examples too

https://github.com/nesquena/rabl

Public free web services for testing soap client

There is a bunch on here:

http://www.webservicex.net/WS/wscatlist.aspx

Just google for "Free WebService" or "Open WebService" and you'll find tons of open SOAP endpoints.

Remember, you can get a WSDL from any ASMX endpoint by adding ?WSDL to the url.

Eclipse Java error: This selection cannot be launched and there are no recent launches

It happens when sometimes we copy or import the project from somewhere. The source folder is a big thing to concern about.

One simple technique is, create a new project, inside the source folder, create a new class and paste the content over there.

It will work...

Hope it helps.

C++ calling base class constructors

The default class constructor is called unless you explicitly call another constructor in the derived class. the language specifies this.

Rectangle(int h,int w):
   Shape(h,w)
  {...}

Will call the other base class constructor.

How to change MySQL data directory?

  1. Stop MySQL using the following command:

    sudo /etc/init.d/mysql stop
    
  2. Copy the existing data directory (default located in /var/lib/mysql) using the following command:

    sudo cp -R -p /var/lib/mysql /newpath
    
  3. edit the MySQL configuration file with the following command:

    sudo gedit /etc/mysql/my.cnf   # or perhaps /etc/mysql/mysql.conf.d/mysqld.cnf
    
  4. Look for the entry for datadir, and change the path (which should be /var/lib/mysql) to the new data directory.

  5. In the terminal, enter the command:

    sudo gedit /etc/apparmor.d/usr.sbin.mysqld
    
  6. Look for lines beginning with /var/lib/mysql. Change /var/lib/mysql in the lines with the new path.

  7. Save and close the file.

  8. Restart the AppArmor profiles with the command:

    sudo /etc/init.d/apparmor reload
    
  9. Restart MySQL with the command:

    sudo /etc/init.d/mysql restart
    
  10. Now login to MySQL and you can access the same databases you had before.

Input type=password, don't let browser remember the password

You can use JQuery, select the item by id:

$("input#Password").attr("autocomplete","off");

Or select the item by type:

$("input[type='password']").attr("autocomplete","off");

Or also:

You can use pure Javascript:

document.getElementById('Password').autocomplete = 'off';

How to Scroll Down - JQuery

This can be used in to solve this problem

<div id='scrol'></div> 

in javascript use this

jQuery("div#scrol").scrollTop(jQuery("div#scrol")[0].scrollHeight);

How does Git handle symbolic links?

Git just stores the contents of the link (i.e. the path of the file system object that it links to) in a 'blob' just like it would for a normal file. It then stores the name, mode and type (including the fact that it is a symlink) in the tree object that represents its containing directory.

When you checkout a tree containing the link, it restores the object as a symlink regardless of whether the target file system object exists or not.

If you delete the file that the symlink references it doesn't affect the Git-controlled symlink in any way. You will have a dangling reference. It is up to the user to either remove or change the link to point to something valid if needed.

Could not find or load main class org.gradle.wrapper.GradleWrapperMain

You are probably missing gradle-wrapper.jar file under directory gradle/wrapper in your project.

You need to generate this file via this script in build.gradle file as below,

task wrapper(type: Wrapper) {
   gradleVersion = '2.0' // version required
}

and run task:

gradle wrapper

With gradle 2.4 (or higher) you can set up a wrapper without adding a dedicated task:

gradle wrapper --gradle-version 2.3

OR

gradle wrapper --gradle-distribution-url https://myEnterpriseRepository:7070/gradle/distributions/gradle-2.3-bin.zip

All the details can be found this link

Failed to find target with hash string 'android-25'

It seems like that it is only me who are so clumsy, because i have yet to found a solution that my case required.

I am developing a multi-modular project, thus base android module configuration is extracted in single gradle script. All the concrete versions of sdks/libs are also extracted in a script.

A script containing versions looked like this:

...

ext.androidVersions = [
    compile_sdk_version     : '27',
    min_sdk_version         : '19',
    target_sdk_version      : '27',
    build_tool_version      : '27.0.3',
    application_id          : 'com.test.test',
]

...

Not accustomed to groovy syntax my eye has not spotted that the values for compile, min and target sdks were not integers but STRINGS! Therefore a compiler rightfully complained about not being able to find an sdk a version of which would match HASH STRING '27'.

So the solution would be to make sdk's versions integers: ...

ext.androidVersions = [
    compile_sdk_version     : 27,
    min_sdk_version         : 19,
    target_sdk_version      : 27,
    build_tool_version      : '27.0.3',
    application_id          : 'com.test.test',
]

...

Better/Faster to Loop through set or list?

While a set may be what you want structure-wise, the question is what is faster. A list is faster. Your example code doesn't accurately compare set vs list because you're converting from a list to a set in set_loop, and then you're creating the list you'll be looping through in list_loop. The set and list you iterate through should be constructed and in memory ahead of time, and simply looped through to see which data structure is faster at iterating:

ids_list = range(1000000)
ids_set = set(ids)
def f(x):
    for i in x:
         pass

%timeit f(ids_set)
#1 loops, best of 3: 214 ms per loop
%timeit f(ids_list)
#1 loops, best of 3: 176 ms per loop

Python: How to check if keys exists and retrieve value from Dictionary in descending priority

One option if the number of keys is small is to use chained gets:

value = myDict.get('lastName', myDict.get('firstName', myDict.get('userName')))

But if you have keySet defined, this might be clearer:

value = None
for key in keySet:
    if key in myDict:
        value = myDict[key]
        break

The chained gets do not short-circuit, so all keys will be checked but only one used. If you have enough possible keys that that matters, use the for loop.

How to calculate the SVG Path for an arc (of a circle)

Note for the answer-seekers (who I also was) - if using arc is not obligatory, a far simpler solution to draw a part-circle is to use stroke-dasharray of SVG <circle>.

Divide dash array into two elements, and scale their range to the desired angle. Starting angle can be adjusted using stroke-dashoffset.

Not a single cosine in sight.

Full example with explanations: https://codepen.io/mjurczyk/pen/wvBKOvP

How to add "active" class to Html.ActionLink in ASP.NET MVC

You can try this: In my case i am loading menu from database based on role based access, Write the code on your every view which menu your want to active based on your view.

<script type="text/javascript">
        $(document).ready(function () {         
            $('li.active active-menu').removeClass('active active-menu');
            $('a[href="/MgtCustomer/Index"]').closest('li').addClass('active active-menu');
        });
</script>

What underlies this JavaScript idiom: var self = this?

As mentioned several times above, 'self' is simply being used to keep a reference to 'this' prior to entering the funcition. Once in the function 'this' refers to something else.

Print the contents of a DIV

Using Jquery, simply use this function:

<script>
function printContent(el){
var restorepage = $('body').html();
var printcontent = $('#' + el).clone();
$('body').empty().html(printcontent);
window.print();
$('body').html(restorepage);
}
</script>

Your print button will look like this:

<button id="print" onclick="printContent('id name of your div');" >Print</button>

Edit: If you DO have form data that you need to keep, clone won't copy that, so you'll just need to grab all the form data and replace it after restore as so:

<script>
function printContent(el){
var restorepage = $('body').html();
var printcontent = $('#' + el).clone();
var enteredtext = $('#text').val();
$('body').empty().html(printcontent);
window.print();
$('body').html(restorepage);
$('#text').html(enteredtext);
}
</script>
<textarea id="text"></textarea>

Align button to the right

The bootstrap 4.0.0 file you are getting from cdn doesn't have a pull-right (or pull-left) class. The v4 is in alpha, so there are many issues like that.

There are 2 options:

1) Reverse to bootstrap 3.3.7

2) Write your own CSS.

error LNK2038: mismatch detected for '_MSC_VER': value '1600' doesn't match value '1700' in CppFile1.obj

I was importing also some projects from VS2010 to VS 2012. I had the same errors. The errors disappeared when I set back Properties > Config. Properties > General > Platform Toolset to v100 (VS2010). That might not be the correct approach, however.

The calling thread cannot access this object because a different thread owns it

Another good use for Dispatcher.Invoke is for immediately updating the UI in a function that performs other tasks:

// Force WPF to render UI changes immediately with this magic line of code...
Dispatcher.Invoke(new Action(() => { }), DispatcherPriority.ContextIdle);

I use this to update button text to "Processing..." and disable it while making WebClient requests.

How do I get the height of a div's full content with jQuery?

Element.scrollHeight is a property, not a function, as noted here. As noted here, the scrollHeight property is only supported after IE8. If you need it to work before that, temporarily set the CSS overflow and height to auto, which will cause the div to take the maximum height it needs. Then get the height, and change the properties back to what they were before.

Dynamically create Bootstrap alerts box through JavaScript

I found that AlertifyJS is a better alternative and have a Bootstrap theme.

alertify.alert('Alert Title', 'Alert Message!', function(){ alertify.success('Ok'); });

Also have a 4 components: Alert, Confirm, Prompt and Notifier.

Exmaple: JSFiddle

Content Type text/xml; charset=utf-8 was not supported by service

For anyone who lands here by searching:

content type 'application/json; charset=utf-8' was not the expected type 'text/xml; charset=utf-8

or some subset of that error:

A similar error was caused in my case by building and running a service without proper attributes. I got this error message when I tried to update the service reference in my client application. It was resolved when I correctly applied [DataContract] and [DataMember] attributes to my custom classes.

This would most likely be applicable if your service was set up and working and then it broke after you edited it.

Click through div to underlying elements

it doesn't work that way. the work around is to manually check the coordinates of the mouse click against the area occupied by each element.

area occupied by an element can found found by 1. getting the location of the element with respect to the top left of the page, and 2. the width and the height. a library like jQuery makes this pretty simple, although it can be done in plain js. adding an event handler for mousemove on the document object will provide continuous updates of the mouse position from the top and left of the page. deciding if the mouse is over any given object consists of checking if the mouse position is between the left, right, top and bottom edges of an element.

PHP Parse error: syntax error, unexpected end of file in a CodeIgniter View

Unexpected end of file means that something else was expected before the PHP parser reached the end of the script.

Judging from your HUGE file, it's probably that you're missing a closing brace (}) from an if statement.

Please at least attempt the following things:

  1. Separate your code from your view logic.
  2. Be consistent, you're using an end ; in some of your embedded PHP statements, and not in others, ie. <?php echo base_url(); ?> vs <?php echo $this->layouts->print_includes() ?>. It's not required, so don't use it (or do, just do one or the other).
  3. Repeated because it's important, separate your concerns. There's no need for all of this code.
  4. Use an IDE, it will help you with errors such as this going forward.

Javascript ES6 export const vs export let

In ES6, imports are live read-only views on exported-values. As a result, when you do import a from "somemodule";, you cannot assign to a no matter how you declare a in the module.

However, since imported variables are live views, they do change according to the "raw" exported variable in exports. Consider the following code (borrowed from the reference article below):

//------ lib.js ------
export let counter = 3;
export function incCounter() {
    counter++;
}

//------ main1.js ------
import { counter, incCounter } from './lib';

// The imported value `counter` is live
console.log(counter); // 3
incCounter();
console.log(counter); // 4

// The imported value can’t be changed
counter++; // TypeError

As you can see, the difference really lies in lib.js, not main1.js.


To summarize:

  • You cannot assign to import-ed variables, no matter how you declare the corresponding variables in the module.
  • The traditional let-vs-const semantics applies to the declared variable in the module.
    • If the variable is declared const, it cannot be reassigned or rebound in anywhere.
    • If the variable is declared let, it can only be reassigned in the module (but not the user). If it is changed, the import-ed variable changes accordingly.

Reference: http://exploringjs.com/es6/ch_modules.html#leanpub-auto-in-es6-imports-are-live-read-only-views-on-exported-values

How to convert a Map to List in Java?

Here's the generic method to get values from map.

public static <T> List<T> ValueListFromMap(HashMap<String, T> map) {
    List<T> thingList = new ArrayList<>();

    for (Map.Entry<String, T> entry : map.entrySet()) {
        thingList.add(entry.getValue());
    }

    return thingList;
}

How to calculate DATE Difference in PostgreSQL?

a simple way would be to cast the dates into timestamps and take their difference and then extract the DAY part.

if you want real difference

select extract(day from 'DATE_A'::timestamp - 'DATE_B':timestamp);

if you want absolute difference

select abs(extract(day from 'DATE_A'::timestamp - 'DATE_B':timestamp));

div inside php echo

You can do the following:

echo '<div class="my_class">';
echo ($cart->count_product > 0) ? $cart->count_product : '';
echo '</div>';

If you want to have it inside your statement, do this:

if($cart->count_product > 0) 
{
    echo '<div class="my_class">'.$cart->count_product.'</div>';
}

You don't need the else statement, since you're only going to output the above when it's truthy anyway.

The ALTER TABLE statement conflicted with the FOREIGN KEY constraint

Please first delete data from that table and then run the migration again. You will get success

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

Yes it's possible. Follow these steps:

  1. Download Xcode 10.2 via this link (you need to be signed in with your Apple Id): https://developer.apple.com/services-account/download?path=/Developer_Tools/Xcode_10.2/Xcode_10.2.xip and install it
  2. Edit Xcode.app/Contents/Info.plist and change the Minimum System Version to 10.13.6
  3. Do the same for Xcode.app/Contents/Developer/Applications/Simulator.app/Contents/Info.plist (might require a restart of Xcode and/or Mac OS to make it open the simulator on run)
  4. Replace Xcode.app/Contents/Developer/usr/bin/xcodebuild with the one from 10.1 (or another version you have currently installed, such as 10.0).
  5. If there are problems with the simulator, reboot your Mac

How to diff a commit with its parent?

Use git show $COMMIT. It'll show you the log message for the commit, and the diff of that particular commit.

Jquery to get the id of selected value from dropdown

Try the change event and selected selector

$('#jobSel').change(function(){
    var optId = $(this).find('option:selected').attr('id')
})

How to make a transparent border using CSS?

use rgba (rgb with alpha transparency):

border: 10px solid rgba(0,0,0,0.5); // 0.5 means 50% of opacity

The alpha transparency variate between 0 (0% opacity = 100% transparent) and 1 (100 opacity = 0% transparent)

POST request with a simple string in body with Alamofire

let parameters = ["foo": "bar"]
              
    // All three of these calls are equivalent
    AF.request("https://httpbin.org/post", method: .post, parameters: parameters)
    AF.request("https://httpbin.org/post", method: .post, parameters: parameters, encoder: URLEncodedFormParameterEncoder.default)
    AF.request("https://httpbin.org/post", method: .post, parameters: parameters, encoder: URLEncodedFormParameterEncoder(destination: .httpBody))
    
    

Changing Tint / Background color of UITabBar

Swift 3 using appearance from your AppDelegate do the following:

UITabBar.appearance().barTintColor = your_color

Select All checkboxes using jQuery

$(document).ready(function() {
    $('#ckbCheckAll').click(function() {
        $('.checkBoxClass').each(function() {
            $(this).attr('checked',!$(this).attr('checked'));
        });
    });
});

OR

$(function () {
    $('#ckbCheckAll').toggle(
        function() {
            $('.checkBoxClass').prop('checked', true);
        },
        function() {
            $('.checkBoxClass').prop('checked', false);
        }
    );
});

LEFT OUTER JOIN in LINQ

Here is a fairly easy to understand version using method syntax:

IEnumerable<JoinPair> outerLeft =
    lefts.SelectMany(l => 
        rights.Where(r => l.Key == r.Key)
              .DefaultIfEmpty(new Item())
              .Select(r => new JoinPair { LeftId = l.Id, RightId = r.Id }));

How to wait for the 'end' of 'resize' event and only then perform an action?

You can use setTimeout() and clearTimeout() in conjunction with jQuery.data:

$(window).resize(function() {
    clearTimeout($.data(this, 'resizeTimer'));
    $.data(this, 'resizeTimer', setTimeout(function() {
        //do something
        alert("Haven't resized in 200ms!");
    }, 200));
});

Update

I wrote an extension to enhance jQuery's default on (& bind)-event-handler. It attaches an event handler function for one or more events to the selected elements if the event was not triggered for a given interval. This is useful if you want to fire a callback only after a delay, like the resize event, or else. https://github.com/yckart/jquery.unevent.js

;(function ($) {
    var methods = { on: $.fn.on, bind: $.fn.bind };
    $.each(methods, function(k){
        $.fn[k] = function () {
            var args = [].slice.call(arguments),
                delay = args.pop(),
                fn = args.pop(),
                timer;

            args.push(function () {
                var self = this,
                    arg = arguments;
                clearTimeout(timer);
                timer = setTimeout(function(){
                    fn.apply(self, [].slice.call(arg));
                }, delay);
            });

            return methods[k].apply(this, isNaN(delay) ? arguments : args);
        };
    });
}(jQuery));

Use it like any other on or bind-event handler, except that you can pass an extra parameter as a last:

$(window).on('resize', function(e) {
    console.log(e.type + '-event was 200ms not triggered');
}, 200);

http://jsfiddle.net/ARTsinn/EqqHx/

Installing Java on OS X 10.9 (Mavericks)

The right place to download the JDK for Java 7 is Java SE Downloads.

All the other links provided above, as far as I can tell, either provide the JRE or Java 6 downloads (incidentally, if you want to run Eclipse or other IDEs, like IntelliJ IDEA, you will need the JDK, not the JRE).

Regarding IntelliJ IDEA - that will still ask you to install Java 6 as it apparently needs an older class loader or something: just follow the instructions when the dialog pop-up appears and it will install the JDK 6 in the right place.

Afterwards, you will need to do the sudo ln -snf mentioned in the answer above:

sudo ln -nsf /Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents \
    /System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK

(copied here as it was mentioned that "above" may eventually not make sense as answers are re-sorted).

I also set my JAVA_HOME to point to where jdk_1.7.0_xx.jdk was installed:

export JAVA_HOME="/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home"

Then add that to your PATH:

export PATH=$JAVA_HOME/bin:$PATH

The alternative is to fuzz around with Apple's insane maze of hyperlinks, but honestly life is too short to bother.

java: use StringBuilder to insert at the beginning

This thread is quite old, but you could also think about a recursive solution passing the StringBuilder to fill. This allows to prevent any reverse processing etc. Just need to design your iteration with a recursion and carefully decide for an exit condition.

public class Test {

    public static void main(String[] args) {
        StringBuilder sb = new StringBuilder();
        doRecursive(sb, 100, 0);
        System.out.println(sb.toString());
    }

    public static void doRecursive(StringBuilder sb, int limit, int index) {
        if (index < limit) {
            doRecursive(sb, limit, index + 1);
            sb.append(Integer.toString(index));
        }
    }
}

How enable auto-format code for Intellij IDEA?

I know this question is quite old but there is actually a Save Actions plugin for IntelliJ that can be configured to format the code automatically.

"Proxy server connection failed" in google chrome

Internet explorer has a reset to factory button and luckily so does chrome! try the link below and let us know. the other option is to stop chrome and delete the c:\users\%username%\appdata\local\google folder entirely then reinstall chrome but this will loose all you local settings and data.

Google doc on how to factory reset: https://support.google.com/chrome/answer/3296214?hl=en

Display last git commit comment

If you want to see just the subject (first line) of the commit message:

git log -1 --format=%s

This was not previously documented in any answer. Alternatively, the approach by nos also shows it.

Reference:

How to avoid soft keyboard pushing up my layout?

For future readers.

I wanted specific control over this issue, so this is what I did:

From a fragment or activity, hide your other views (that aren't needed while the keyboard is up), then restore them to solve this problem:

rootView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
     @Override
     public void onGlobalLayout() {
        Rect r = new Rect();
        rootView.getWindowVisibleDisplayFrame(r);
        int heightDiff = rootView.getRootView().getHeight() - (r.bottom - r.top);

        if (heightDiff > 100) { // if more than 100 pixels, its probably a keyboard...
           //ok now we know the keyboard is up...
           view_one.setVisibility(View.GONE);
           view_two.setVisibility(View.GONE);

        } else {
           //ok now we know the keyboard is down...
           view_one.setVisibility(View.VISIBLE);
           view_two.setVisibility(View.VISIBLE);       
        }
     }
});

Cannot connect to local SQL Server with Management Studio

Try to see, if the service "SQL Server (MSSQLSERVER)" it's started, this solved my problem.

The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or dataframe

[] extracts a list, [[]] extracts elements within the list

alist <- list(c("a", "b", "c"), c(1,2,3,4), c(8e6, 5.2e9, -9.3e7))

str(alist[[1]])
 chr [1:3] "a" "b" "c"

str(alist[1])
List of 1
 $ : chr [1:3] "a" "b" "c"

str(alist[[1]][1])
 chr "a"

Adding an external directory to Tomcat classpath

Just specify it in shared.loader or common.loader property of /conf/catalina.properties.

What is going wrong when Visual Studio tells me "xcopy exited with code 4"

As other answers explain, exit code 4 may have many causes.

I noticed a case, where resulting path names exceeded the maximum allowed length (just like here).

I have replaced xcopy by robocopy for the affected post build event; robocopy seems to handle paths slightly different and was able to complete the copy task that xcopy was unable to handle.

how to get the last character of a string?

You can use this simple ES6 method

_x000D_
_x000D_
const lastChar = (str) => str.split('').reverse().join(',').replace(',', '')[str.length === str.length + 1 ? 1 : 0];_x000D_
_x000D_
_x000D_
// example_x000D_
console.log(lastChar("linto.yahoo.com."));
_x000D_
_x000D_
_x000D_

This will work in every browsers.

Refresh (reload) a page once using jQuery?

Use this instead

function timedRefresh(timeoutPeriod) {
    setTimeout("location.reload(true);",timeoutPeriod);
}

<a href="javascript:timedRefresh(2000)">image</a>

Abstraction VS Information Hiding VS Encapsulation

Both Abstraction and Encapsulation are two of the four basic OOP concepts which allow you to model real-world things into objects so that you can implement them in your program and code. Many beginners get confused between Abstraction and Encapsulation because they both look very similar. If you ask someone what is Abstraction, he will tell that it's an OOP concept which focuses on relevant information by hiding unnecessary detail, and when you ask about Encapsulation, many will tell that it's another OOP concept which hides data from outside world. The definitions are not wrong as both Abstraction and Encapsulation does hide something, but the key difference is on intent.

Abstraction hides complexity by giving you a more abstract picture, a sort of 10,000 feet view, while Encapsulation hides internal working so that you can change it later. In other words, Abstraction hides details at the design level, while Encapsulation hides details at the implementation level.

Property 'value' does not exist on type 'Readonly<{}>'

event.target is of type EventTarget which doesn't always have a value. If it's a DOM element you need to cast it to the correct type:

handleChange(event) {
    this.setState({value: (event.target as HTMLInputElement).value});
}

This will infer the "correct" type for the state variable as well though being explicit is probably better

Last non-empty cell in a column

For Microsoft office 2013

"Last but one" of a non empty row:

=OFFSET(Sheet5!$C$1,COUNTA(Sheet5!$C:$C)-2,0)

"Last" non empty row:

=OFFSET(Sheet5!$C$1,COUNTA(Sheet5!$C:$C)-1,0)

How to check if type of a variable is string?

s = '123'
issubclass(s.__class__, str)

PHP string concatenation

I think this code should work fine

while ($personCount < 10) {
$result = $personCount . "people ';
$personCount++;
}
// do not understand why do you need the (+) with the result.
echo $result;

Dynamically replace img src attribute with jQuery

You need to check out the attr method in the jQuery docs. You are misusing it. What you are doing within the if statements simply replaces all image tags src with the string specified in the 2nd parameter.

http://api.jquery.com/attr/

A better way to approach replacing a series of images source would be to loop through each and check it's source.

Example:

$('img').each(function () {
  var curSrc = $(this).attr('src');
  if ( curSrc === 'http://example.com/smith.gif' ) {
      $(this).attr('src', 'http://example.com/johnson.gif');
  }
  if ( curSrc === 'http://example.com/williams.gif' ) {
      $(this).attr('src', 'http://example.com/brown.gif');
  }
});

Sending a JSON HTTP POST request from Android

Posting parameters Using POST:-

URL url;
URLConnection urlConn;
DataOutputStream printout;
DataInputStream  input;
url = new URL (getCodeBase().toString() + "env.tcgi");
urlConn = url.openConnection();
urlConn.setDoInput (true);
urlConn.setDoOutput (true);
urlConn.setUseCaches (false);
urlConn.setRequestProperty("Content-Type","application/json");   
urlConn.setRequestProperty("Host", "android.schoolportal.gr");
urlConn.connect();  
//Create JSONObject here
JSONObject jsonParam = new JSONObject();
jsonParam.put("ID", "25");
jsonParam.put("description", "Real");
jsonParam.put("enable", "true");

The part which you missed is in the the following... i.e., as follows..

// Send POST output.
printout = new DataOutputStream(urlConn.getOutputStream ());
printout.writeBytes(URLEncoder.encode(jsonParam.toString(),"UTF-8"));
printout.flush ();
printout.close ();

The rest of the thing you can do it.

Asp.net Validation of viewstate MAC failed

I have faced the similar issue on my website hosted on IIS. This issue generally because of IIS Application pool settings. As application pool recycle after some time that caused the issue for me.

Following steps help me to fix the issue:

  1. Open App pool of you website on IIS.
  2. Go to Advance settings on right hand pane.
  3. Scroll down to Process Model
  4. Change Idle Time-out minutes to 20 or number of minutes you don't want to recycle your App pool.

enter image description here

Then try again . It will solve your issue.

<embed> vs. <object>

You could also use the iframe method, although this is not cross browser compatible (eg. not working in chromium or android and probably others -> instead prompts to download). It works with dataURL's and normal URLS, not sure if the other examples work with dataURLS (please let me know if the other examples work with dataURLS?)

 <iframe class="page-icon preview-pane" frameborder="0" height="352" width="396" src="data:application/pdf;base64, ..DATAURLHERE!... "></iframe>

SQLite "INSERT OR REPLACE INTO" vs. "UPDATE ... WHERE"

I'm currently working on such a statement and figured out another fact to notice: INSERT OR REPLACE will replace any values not supplied in the statement. For instance if your table contains a column "lastname" which you didn't supply a value for, INSERT OR REPLACE will nullify the "lastname" if possible (constraints allow it) or fail.

Mongoose limit/offset and count query

After having to tackle this issue myself, I would like to build upon user854301's answer.

Mongoose ^4.13.8 I was able to use a function called toConstructor() which allowed me to avoid building the query multiple times when filters are applied. I know this function is available in older versions too but you'll have to check the Mongoose docs to confirm this.

The following uses Bluebird promises:

let schema = Query.find({ name: 'bloggs', age: { $gt: 30 } });

// save the query as a 'template'
let query = schema.toConstructor();

return Promise.join(
    schema.count().exec(),
    query().limit(limit).skip(skip).exec(),

    function (total, data) {
        return { data: data, total: total }
    }
);

Now the count query will return the total records it matched and the data returned will be a subset of the total records.

Please note the () around query() which constructs the query.

Failure [INSTALL_FAILED_INVALID_APK]

I meet the similar issue, but it auto fixed after i reboot my Ubuntu PC,for I install some Ubuntu(12.04)app update,which leads to this issue.

How do I use StringUtils in Java?

The mostly used StringUtils class is the Apache Commons Lang StringUtils (org.apache.commons.lang3.StringUtils). To use this class you first have to download the Apache Commons Lang3 package then you have to add it to your project libraries.

You can go to this link to get more details: http://examples.javacodegeeks.com/core-java/apache/commons/lang3/stringutils/org-apache-commons-lang3-stringutils-example/

Sorting hashmap based on keys

You can use TreeMap which will store values in sorted form.

Map <String, String> map = new TreeMap <String, String>();

Bootstrap modal link

Please remove . from your target it should be a id

<a href="#bannerformmodal" data-toggle="modal" data-target="#bannerformmodal">Load me</a>

Also you have to give your modal id like below

<div class="modal fade bannerformmodal" tabindex="-1" role="dialog" aria-labelledby="bannerformmodal" aria-hidden="true" id="bannerformmodal">

Here is the solution in a fiddle.

Use different Python version with virtualenv

These two commands should work fine.

virtualenv -p python2 myenv (For python2)

virtualenv -p python3 myenv (For python3)

Order by in Inner Join

I found this to be an issue when joining but you might find this blog useful in understanding how Joins work in the back. How Joins Work..

[Edited] @Shree Thank you for pointing that out. On the paragraph of Merge Join. It mentions on how joins work...

Like hash join, merge join consists of two steps. First, both tables of the join are sorted on the join attribute. This can be done with just two passes through each table via an external merge sort. Finally, the result tuples are generated as the next ordered element is pulled from each table and the join attributes are compared

.

What does iterator->second mean?

I'm sure you know that a std::vector<X> stores a whole bunch of X objects, right? But if you have a std::map<X, Y>, what it actually stores is a whole bunch of std::pair<const X, Y>s. That's exactly what a map is - it pairs together the keys and the associated values.

When you iterate over a std::map, you're iterating over all of these std::pairs. When you dereference one of these iterators, you get a std::pair containing the key and its associated value.

std::map<std::string, int> m = /* fill it */;
auto it = m.begin();

Here, if you now do *it, you will get the the std::pair for the first element in the map.

Now the type std::pair gives you access to its elements through two members: first and second. So if you have a std::pair<X, Y> called p, p.first is an X object and p.second is a Y object.

So now you know that dereferencing a std::map iterator gives you a std::pair, you can then access its elements with first and second. For example, (*it).first will give you the key and (*it).second will give you the value. These are equivalent to it->first and it->second.

How to export non-exportable private key from store

Gentil Kiwi's answer is correct. He developed this mimikatz tool that is able to retrieve non-exportable private keys.

However, his instructions are outdated. You need:

  1. Download the lastest release from https://github.com/gentilkiwi/mimikatz/releases

  2. Run the cmd with admin rights in the same machine where the certificate was requested

  3. Change to the mimikatz bin directory (Win32 or x64 version)

  4. Run mimikatz

  5. Follow the wiki instructions and the .pfx file (protected with password mimikatz) will be placed in the same folder of the mimikatz bin

mimikatz # crypto::capi
Local CryptoAPI patched

mimikatz # privilege::debug
Privilege '20' OK

mimikatz # crypto::cng
"KeyIso" service patched

mimikatz # crypto::certificates /systemstore:local_machine /store:my /export
* System Store : 'local_machine' (0x00020000)
* Store : 'my'

  1. example.domain.local
         Key Container : example.domain.local
         Provider : Microsoft Software Key Storage Provider
         Type : CNG Key (0xffffffff)
         Exportable key : NO
         Key size : 2048
         Public export : OK - 'local_machine_my_0_example.domain.local.der'
         Private export : OK - 'local_machine_my_0_example.domain.local.pfx'

Why was the name 'let' chosen for block-scoped variable declarations in JavaScript?

Let is a mathematical statement that was adopted by early programming languages like Scheme and Basic. Variables are considered low level entities not suitable for higher levels of abstraction, thus the desire of many language designers to introduce similar but more powerful concepts like in Clojure, F#, Scala, where let might mean a value, or a variable that can be assigned, but not changed, which in turn lets the compiler catch more programming errors and optimize code better.

JavaScript has had var from the beginning, so they just needed another keyword, and just borrowed from dozens of other languages that use let already as a traditional keyword as close to var as possible, although in JavaScript let creates block scope local variable instead.

When saving, how can you check if a field has changed?

Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).

class Person(models.Model):
    name = models.CharField()

    __original_name = None

    def __init__(self, *args, **kwargs):
        super(Person, self).__init__(*args, **kwargs)
        self.__original_name = self.name

    def save(self, force_insert=False, force_update=False, *args, **kwargs):
        if self.name != self.__original_name:
            # name changed - do something here

        super(Person, self).save(force_insert, force_update, *args, **kwargs)
        self.__original_name = self.name

How can I print the contents of an array horizontally?

int[] n=new int[5];

for (int i = 0; i < 5; i++)
{
    n[i] = i + 100;
}

foreach (int j in n)
{
    int i = j - 100;

    Console.WriteLine("Element [{0}]={1}", i, j);
    i++;
}

UIScrollView not scrolling

If none of the other solutions work for you, double check that your scroll view actually is a UIScrollView in Interface Builder.

At some point in the last few days, my UIScrollView spontaneously changed type to a UIView, even though its class said UIScrollView in the inspector. I'm using Xcode 5.1 (5B130a).

You can either create a new scroll view and copy the measurements, settings and constraints from the old view, or you can manually change your view to a UIScrollView in the xib file. I did a compare and found the following differences:

Original:

<scrollView clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="scaleToFill" directionalLockEnabled="YES" bounces="NO" pagingEnabled="YES" showsHorizontalScrollIndicator="NO" showsVerticalScrollIndicator="NO" translatesAutoresizingMaskIntoConstraints="NO" id="Wsk-WB-LMH">
...
</scrollView>

After type spontaneously changed:

<view clearsContextBeforeDrawing="NO" contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" customClass="UIScrollView" id="qRn-TP-cXd">
...
</view>

So I replaced the <view> line with my original <scrollView> line.

I also replaced the view's close tag </view> with </scrollView>.

Be sure to keep the id the same as the current view, in this case: id="qRn-TP-cXd".

I also had to flush the xib from Xcode's cache by deleting the app's derived data:

  • Xcode->Window->Organizer->Projects, choose your project, on the Derived Data line, click Delete...

Or if using a device:

  • Xcode->Window->Organizer->Device, choose your device->Applications, choose your app, click (-)

Now clean the project, and remove the app from the simulator/device:

  • Xcode->Product->Clean
  • iOS Simulator/device->press and hold the app->click the (X) to remove it

You should then be able to build and run your app and have scrolling functionality again.

P.S. I didn't have to set the scroll view's content size in viewDidLayoutSubviews or turn off auto layout, but YMMV.

Better solution without exluding fields from Binding

You should not use your domain models in your views. ViewModels are the correct way to do it.

You need to map your domain model's necessary fields to viewmodel and then use this viewmodel in your controllers. This way you will have the necessery abstraction in your application.

If you never heard of viewmodels, take a look at this.

Visual Studio 64 bit?

no, but it runs fine on win64, and can create win64 .EXEs

Modify table: How to change 'Allow Nulls' attribute from not null to allow null

For MySQL, MariaDB

ALTER TABLE [table name] MODIFY COLUMN [column name] [data type] NULL

Use MODIFY COLUMN instead of ALTER COLUMN.

How to wrap text of HTML button with fixed width?

   white-space: normal;
   word-wrap: break-word;

"Both" worked for me.

Get model's fields in Django

This is something that is done by Django itself when building a form from a model. It is using the _meta attribute, but as Bernhard noted, it uses both _meta.fields and _meta.many_to_many. Looking at django.forms.models.fields_for_model, this is how you could do it:

opts = model._meta
for f in sorted(opts.fields + opts.many_to_many):
    print '%s: %s' % (f.name, f)

Variable number of arguments in C++?

Apart from varargs or overloading, you could consider to aggregate your arguments in a std::vector or other containers (std::map for example). Something like this:

template <typename T> void f(std::vector<T> const&);
std::vector<int> my_args;
my_args.push_back(1);
my_args.push_back(2);
f(my_args);

In this way you would gain type safety and the logical meaning of these variadic arguments would be apparent.

Surely this approach can have performance issues but you should not worry about them unless you are sure that you cannot pay the price. It is a sort of a a "Pythonic" approach to c++ ...

Measure string size in Bytes in php

Do you mean byte size or string length?

Byte size is measured with strlen(), whereas string length is queried using mb_strlen(). You can use substr() to trim a string to X bytes (note that this will break the string if it has a multi-byte encoding - as pointed out by Darhazer in the comments) and mb_substr() to trim it to X characters in the encoding of the string.

Pandas sort by group aggregate and column

Here's a more concise approach...

df['a_bsum'] = df.groupby('A')['B'].transform(sum)
df.sort(['a_bsum','C'], ascending=[True, False]).drop('a_bsum', axis=1)

The first line adds a column to the data frame with the groupwise sum. The second line performs the sort and then removes the extra column.

Result:

    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

NOTE: sort is deprecated, use sort_values instead

Restore a deleted file in the Visual Studio Code Recycle Bin

If you just deleted the file, know that VSCode 1.52 (Dec. 2020) will support:

Undo file operations in Explorer

Explorer now supports Undo and Redo for all file operations: delete, rename, copy, move, new file and new folder.

Make sure the focus is in the Explorer and trigger the Undo or Redo commands and your last file operation will be undone or redone respectively.
Keep in mind that we have separate undo stacks for the editor and the explorer and we choose which one to undo based on focus.

Explorer Undo -- https://media.githubusercontent.com/media/microsoft/vscode-docs/vnext/release-notes/images/1_52/explorer-undo.gif

How exactly does the android:onClick XML attribute differ from setOnClickListener?

Supporting Ruivo's answer, yes you have to declare method as "public" to be able to use in Android's XML onclick - I am developing an app targeting from API Level 8 (minSdk...) to 16 (targetSdk...).

I was declaring my method as private and it caused error, just declaring it as public works great.

keycode and charcode

keyCode and which represent the actual keyboard key pressed in the form of a numeric value. The reason both exist is that keyCode is available within Internet Explorer while which is available in W3C browsers like FireFox.

charCode is similar, but in this case you retrieve the Unicode value of the character pressed. For example, the letter "A."

The JavaScript expression:

var keyCode = e.keyCode ? e.keyCode : e.charCode;

Essentially says the following:

If the e.keyCode property exists, set variable keyCode to its value. Otherwise, set variable keyCode to the value of the e.charCode property.

Note that retrieving the keyCode or charCode properties typically involve figuring out differences between the event models in IE and in W3C. Some entails writing code like the following:

/*
 get the event object: either window.event for IE 
 or the parameter e for other browsers
*/
var evt = window.event ? window.event : e;
/*
 get the numeric value of the key pressed: either 
 event.keyCode for IE for e.which for other browsers
*/
var keyCode = evt.keyCode ? evt.keyCode : e.which;

EDIT: Corrections to my explanation of charCode as per Tor Haugen's comments.

How to create a file name with the current date & time in Python?

Change this line

filename1 = datetime.now().strftime("%Y%m%d-%H%M%S")

To

filename1 = datetime.datetime.now().strftime("%Y%m%d-%H%M%S")

Note the extra datetime. Alternatively, change your import datetime to from datetime import datetime

Check if a number is int or float

I like @ninjagecko's answer the most.

This would also work:

for Python 2.x

isinstance(n, (int, long, float)) 

Python 3.x doesn't have long

isinstance(n, (int, float))

there is also type complex for complex numbers

How to calculate the angle between a line and the horizontal axis?

import math
from collections import namedtuple


Point = namedtuple("Point", ["x", "y"])


def get_angle(p1: Point, p2: Point) -> float:
    """Get the angle of this line with the horizontal axis."""
    dx = p2.x - p1.x
    dy = p2.y - p1.y
    theta = math.atan2(dy, dx)
    angle = math.degrees(theta)  # angle is in (-180, 180]
    if angle < 0:
        angle = 360 + angle
    return angle

Testing

For testing I let hypothesis generate test cases.

enter image description here

import hypothesis.strategies as s
from hypothesis import given


@given(s.floats(min_value=0.0, max_value=360.0))
def test_angle(angle: float):
    epsilon = 0.0001
    x = math.cos(math.radians(angle))
    y = math.sin(math.radians(angle))
    p1 = Point(0, 0)
    p2 = Point(x, y)
    assert abs(get_angle(p1, p2) - angle) < epsilon

ASP.NET MVC Razor render without encoding

You can also use the WriteLiteral method

How to read XML response from a URL in java?

If you want to print XML directly onto the screen you can use TransformerFactory

URL url = new URL(urlString);
URLConnection conn = url.openConnection();

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(conn.getInputStream());

TransformerFactory transformerFactory= TransformerFactory.newInstance();
Transformer xform = transformerFactory.newTransformer();

// that’s the default xform; use a stylesheet to get a real one
xform.transform(new DOMSource(doc), new StreamResult(System.out));

How to insert &nbsp; in XSLT

One can also do this :

<xsl:text disable-output-escaping="yes"><![CDATA[&nbsp;]]></xsl:text>

From a Sybase Database, how I can get table description ( field names and types)?

sp_help is what you're looking for.

From Sybase online documentation on the sp_help system procedure:

Description

Reports information about a database object (any object listed in sysobjects) and about system or user-defined datatypes, as well as computed columns and function-based indexes. Column displays optimistic_index_lock.

Syntax

sp_help [objname]

[...]

Here is the (partial) output for the publishers table (pasted from Using sp_help on database objects):

Name               Owner        Object_type     Create_date 
----------------   -----------  -------------   ------------------------------
publishers         dbo          user table      Nov 9 2004 9:57AM

(1 row affected)
Column_name Type     Length   Prec  Scale   Nulls   Default_name   Rule_name
----------- -------  ------   ----- ------- ------- -------------- ---------- 
pub_id      char          4    NULL  NULL        0  NULL           pub_idrule
pub_name    varchar      40    NULL  NULL        1  NULL           NULL
city        varchar      20    NULL  NULL        1  NULL           NULL
state       char          2    NULL  NULL        1  NULL           NULL
Access_Rule_name    Computed_Column_object     Identity
------------------- -------------------------  ------------
NULL                NULL                                  0
NULL                NULL                                  0
NULL                NULL                                  0
NULL                NULL                                  0

Still quoting Using sp_help on database objects:

If you execute sp_help without supplying an object name, the resulting report shows each object in sysobjects, along with its name, owner, and object type. Also shown is each user-defined datatype in systypes and its name, storage type, length, whether null values are allowed, and any defaults or rules bound to it. The report also notes if any primary or foreign key columns have been defined for a table or view.

Reverse the ordering of words in a string

reverse the string and then, in a second pass, reverse each word...

in c#, completely in-place without additional arrays:

static char[] ReverseAllWords(char[] in_text)
{
    int lindex = 0;
    int rindex = in_text.Length - 1;
    if (rindex > 1)
    {
        //reverse complete phrase
        in_text = ReverseString(in_text, 0, rindex);

        //reverse each word in resultant reversed phrase
        for (rindex = 0; rindex <= in_text.Length; rindex++)
        {
            if (rindex == in_text.Length || in_text[rindex] == ' ')
            {
                in_text = ReverseString(in_text, lindex, rindex - 1);
                lindex = rindex + 1;
            }
        }
    }
    return in_text;
}

static char[] ReverseString(char[] intext, int lindex, int rindex)
{
    char tempc;
    while (lindex < rindex)
    {
        tempc = intext[lindex];
        intext[lindex++] = intext[rindex];
        intext[rindex--] = tempc;
    }
    return intext;
}

Case vs If Else If: Which is more efficient?

It seems that the compiler is better in optimizing a switch-statement than an if-statement.

The compiler doesn't know if the order of evaluating the if-statements is important to you, and can't perform any optimizations there. You could be calling methods in the if-statements, influencing variables. With the switch-statement it knows that all clauses can be evaluated at the same time and can put them in whatever order is most efficient.

Here's a small comparison:
http://www.blackwasp.co.uk/SpeedTestIfElseSwitch.aspx

How to put wildcard entry into /etc/hosts?

Here is the configuration for those trying to accomplish the original goal (wildcards all pointing to same codebase -- install nothing, dev environment ie, XAMPP)

hosts file (add an entry)

file: /etc/hosts (non-windows)

127.0.0.1   example.local

httpd.conf configuration (enable vhosts)

file: /XAMPP/etc/httpd.conf

# Virtual hosts
Include etc/extra/httpd-vhosts.conf

httpd-vhosts.conf configuration

file: XAMPP/etc/extra/httpd-vhosts.conf

<VirtualHost *:80>
    ServerAdmin [email protected]
    DocumentRoot "/path_to_XAMPP/htdocs"
    ServerName example.local
    ServerAlias *.example.local
#    SetEnv APP_ENVIRONMENT development
#    ErrorLog "logs/example.local-error_log"
#    CustomLog "logs/example.local-access_log" common
</VirtualHost>

restart apache

create pac file:

save as whatever.pac wherever you want to and then load the file in the browser's network>proxy>auto_configuration settings (reload if you alter this)

function FindProxyForURL(url, host) {
  if (shExpMatch(host, "*example.local")) {
    return "PROXY example.local";
  }
  return "DIRECT";
}

Java synchronized method lock on object, or method?

Yes, it will block the other method because synchronized method applies to the WHOLE class object as pointed .... but anyway it will block the other thread execution ONLY while performing the sum in whatever method addA or addB it enters, because when it finish ... the one thread will FREE the object and the other thread will access the other method and so on perfectly working.

I mean the "synchronized" is made precisely for blocking the other thread from accessing another while in a specific code execution. SO FINALLY THIS CODE WILL WORK FINE.

As a final note, if there is an 'a' and 'b' variables, not just an unique variable 'a' or whatever other name, there is no need to synchronize this methods cause it is perfectly safe accesing other var (Other memory location).

class X {

private int a;
private int b;

public void addA(){
    a++;
}

public void addB(){
    b++;
}}

Will work as well

Is it possible to style a mouseover on an image map using CSS?

You could use Canvas

in HTML, simply add a canva

<canvas id="locations" width="400" height="300" style="border:1px solid #d3d3d3;">
Your browser can't read canvas</canvas>

And in Javascript (only an example, that will draw a rectangle on the picture)

var c = document.getElementById("locations");
var ctx = c.getContext("2d");
var img = new Image(); 
img.src = '{main_photo}';
img.onload = function() {    // after the pic is loaded
    ctx.drawImage(this,0,0); // add the picture
    ctx.beginPath();         // start the rectangle
    ctx.moveTo(50,50);
    ctx.lineTo(200,50);
    ctx.lineTo(200,200);
    ctx.lineTo(50,200);
    ctx.lineTo(50,50);

    ctx.strokeStyle = "sienna"; // set color
    ctx.stroke();               // apply color
    ctx.lineWidth = 5;
    // ctx.closePath();
};

How to check if an integer is within a range of numbers in PHP?

I created a function to check if times in an array overlap somehow:

    /**
     * Function to check if there are overlapping times in an array of \DateTime objects.
     *
     * @param $ranges
     *
     * @return \DateTime[]|bool
     */
    public function timesOverlap($ranges) {
        foreach ($ranges as $k1 => $t1) {
            foreach ($ranges as $k2 => $t2) {
                if ($k1 != $k2) {
                    /* @var \DateTime[] $t1 */
                    /* @var \DateTime[] $t2 */
                    $a = $t1[0]->getTimestamp();
                    $b = $t1[1]->getTimestamp();
                    $c = $t2[0]->getTimestamp();
                    $d = $t2[1]->getTimestamp();

                    if (($c >= $a && $c <= $b) || $d >= $a && $d <= $b) {
                        return true;
                    }
                }
            }
        }

        return false;
    }

Why does this code using random strings print "hello world"?

Random always return the same sequence. It's used for shuffling arrays and other operations as permutations.

To get different sequences, it's necessary initialize the sequence in some position, called "seed".

The randomSting get the random number in the i position (seed = -229985452) of the "random" sequence. Then uses the ASCII code for the next 27 character in the sequence after the seed position until this value are equal to 0. This return the "hello". The same operation is done for "world".

I think that the code did not work for any other words. The guy that programmed that knows the random sequence very well.

It's very great geek code!

Absolute Positioning & Text Alignment

Maybe specifying a width would work. When you position:absolute an element, it's width will shrink to the contents I believe.

What's the difference between HTML 'hidden' and 'aria-hidden' attributes?

ARIA (Accessible Rich Internet Applications) defines a way to make Web content and Web applications more accessible to people with disabilities.

The hidden attribute is new in HTML5 and tells browsers not to display the element. The aria-hidden property tells screen-readers if they should ignore the element. Have a look at the w3 docs for more details:

https://www.w3.org/WAI/PF/aria/states_and_properties#aria-hidden

Using these standards can make it easier for disabled people to use the web.

using "if" and "else" Stored Procedures MySQL

The problem is you either haven't closed your if or you need an elseif:

create procedure checando(
    in nombrecillo varchar(30),
    in contrilla varchar(30), 
    out resultado int)
begin 

    if exists (select * from compas where nombre = nombrecillo and contrasenia = contrilla) then
        set resultado = 0;
    elseif exists (select * from compas where nombre = nombrecillo) then
        set resultado = -1;
    else 
        set resultado = -2;
    end if;
end;

How to add a line to a multiline TextBox?

The "Lines" property of a TextBox is an array of strings. By definition, you cannot add elements to an existing string[], like you can to a List<string>. There is simply no method available for the purpose. You must instead create a new string[] based on the current Lines reference, and assign it to Lines.

Using a little Linq (.NET 3.5 or later):

textBox1.Lines = textBox.Lines.Concat(new[]{"Some Text"}).ToArray();

This code is fine for adding one new line at a time based on user interaction, but for initializing a textbox with a few dozen new lines, it will perform very poorly. If you're setting the initial value of a TextBox, I would either set the Text property directly using a StringBuilder (as other answers have mentioned), or if you're set on manipulating the Lines property, use a List to compile the collection of values and then convert it to an array to assign to Lines:

var myLines = new List<string>();

myLines.Add("brown");
myLines.Add("brwn");
myLines.Add("brn");
myLines.Add("brow");
myLines.Add("br");
myLines.Add("brw");
...

textBox1.Lines = myLines.ToArray();

Even then, because the Lines array is a calculated property, this involves a lot of unnecessary conversion behind the scenes.

Responsive css background images

Try using background-size but using TWO ARGUMENTS One for the width and the other one for the height

background-image:url('../images/bg.png'); 
background-repeat:no-repeat;
background-size: 100% 100%; // Here the first argument will be the width 
// and the second will be the height.
background-position:center;

Get column value length, not column max length of value

LENGTH() does return the string length (just verified). I suppose that your data is padded with blanks - try

SELECT typ, LENGTH(TRIM(t1.typ))
FROM AUTA_VIEW t1;

instead.

As OraNob mentioned, another cause could be that CHAR is used in which case LENGTH() would also return the column width, not the string length. However, the TRIM() approach also works in this case.

Beamer: How to show images as step-by-step images

This is what I did:

\begin{frame}{series of images}
\begin{center}
\begin{overprint}

\only<2>{\includegraphics[scale=0.40]{image1.pdf}}
\hspace{-0.17em}\only<3>{\includegraphics[scale=0.40]{image2.pdf}}
\hspace{-0.34em}\only<4>{\includegraphics[scale=0.40]{image3.pdf}}
\hspace{-0.17em}\only<5>{\includegraphics[scale=0.40]{image4.pdf}}

\only<2-5>{\mbox{\structure{Figure:} something}}

\end{overprint}
\end{center}
\end{frame}

Dividing two integers to produce a float result

Cast the operands to floats:

float ans = (float)a / (float)b;

How to get the current date without the time?

I think you need separately date parts like (day, Month, Year)

DateTime today = DateTime.Today;

Will not work for your case. You can get date separately so you don't need variable today to be as a DateTimeType, so lets just give today variable int Type because the day is only int. So today is 10 March 2020 then the result of

int today = DateTime.Today.Day;

int month = DateTime.Today.Month;

int year = DateTime.Today.Year;

MessageBox.Show(today.ToString()+ " - this is day. "+month.ToString()+ " - this is month. " + year.ToString() + " - this is year");

would be "10 - this is day. 3 - this is month. 2020 - this is year"

How do you get git to always pull from a specific branch?

Your immediate question of how to make it pull master, you need to do what it says. Specify the refspec to pull from in your branch config.

[branch "master"]
    merge = refs/heads/master

SQL Server : SUM() of multiple rows including where clauses

The WHERE clause is always conceptually applied (the execution plan can do what it wants, obviously) prior to the GROUP BY. It must come before the GROUP BY in the query, and acts as a filter before things are SUMmed, which is how most of the answers here work.

You should also be aware of the optional HAVING clause which must come after the GROUP BY. This can be used to filter on the resulting properties of groups after GROUPing - for instance HAVING SUM(Amount) > 0

Spring MVC 4: "application/json" Content Type is not being set correctly

When I upgraded to Spring 4 I needed to update the jackson dependencies as follows:

    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.5.1</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.5.1</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>2.5.1</version>
    </dependency>        

Failed to install Python Cryptography package with PIP and setup.py

I resolved this by upgrading from cryptography 1.9 to 2.4.2

DateDiff to output hours and minutes

Try this query

select
    *,
    Days          = datediff(dd,0,DateDif),
    Hours         = datepart(hour,DateDif),
    Minutes       = datepart(minute,DateDif),
    Seconds       = datepart(second,DateDif),
    MS            = datepart(ms,DateDif)
from
    (select
         DateDif = EndDate-StartDate,
         aa.*
     from
         (  -- Test Data
          Select
              StartDate = convert(datetime,'20090213 02:44:37.923'),
              EndDate   = convert(datetime,'20090715 13:24:45.837')) aa
    ) a

Output

DateDif                  StartDate                EndDate                 Days Hours Minutes Seconds MS
-----------------------  -----------------------  ----------------------- ---- ----- ------- ------- ---
1900-06-02 10:40:07.913  2009-02-13 02:44:37.923  2009-07-15 13:24:45.837 152  10    40      7       913

(1 row(s) affected)

Java verify void method calls n times with Mockito

The necessary method is Mockito#verify:

public static <T> T verify(T mock,
                           VerificationMode mode)

mock is your mocked object and mode is the VerificationMode that describes how the mock should be verified. Possible modes are:

verify(mock, times(5)).someMethod("was called five times");
verify(mock, never()).someMethod("was never called");
verify(mock, atLeastOnce()).someMethod("was called at least once");
verify(mock, atLeast(2)).someMethod("was called at least twice");
verify(mock, atMost(3)).someMethod("was called at most 3 times");
verify(mock, atLeast(0)).someMethod("was called any number of times"); // useful with captors
verify(mock, only()).someMethod("no other method has been called on the mock");

You'll need these static imports from the Mockito class in order to use the verify method and these verification modes:

import static org.mockito.Mockito.atLeast;
import static org.mockito.Mockito.atLeastOnce;
import static org.mockito.Mockito.atMost;
import static org.mockito.Mockito.never;
import static org.mockito.Mockito.only;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;

So in your case the correct syntax will be:

Mockito.verify(mock, times(4)).send()

This verifies that the method send was called 4 times on the mocked object. It will fail if it was called less or more than 4 times.


If you just want to check, if the method has been called once, then you don't need to pass a VerificationMode. A simple

verify(mock).someMethod("was called once");

would be enough. It internally uses verify(mock, times(1)).someMethod("was called once");.


It is possible to have multiple verification calls on the same mock to achieve a "between" verification. Mockito doesn't support something like this verify(mock, between(4,6)).someMethod("was called between 4 and 6 times");, but we can write

verify(mock, atLeast(4)).someMethod("was called at least four times ...");
verify(mock, atMost(6)).someMethod("... and not more than six times");

instead, to get the same behaviour. The bounds are included, so the test case is green when the method was called 4, 5 or 6 times.

figure of imshow() is too small

I'm new to python too. Here is something that looks like will do what you want to

axes([0.08, 0.08, 0.94-0.08, 0.94-0.08]) #[left, bottom, width, height]
axis('scaled')`

I believe this decides the size of the canvas.

File content into unix variable with newlines

The envdir utility provides an easy way to do this. envdir uses files to represent environment variables, with file names mapping to env var names, and file contents mapping to env var values. If the file contents contain newlines, so will the env var.

See https://pypi.python.org/pypi/envdir

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

try this.. I had it too but now it solved in XP..

C:\ YourFolder >set path=C:\Program Files\Java\jdk1.7.0_09\bin;
C:\ YourFolder >javac YourCode.java

How to add to an existing hash in Ruby

my_hash = {:a => 5}
my_hash[:key] = "value"

How to change port number in vue-cli project

In my vue project in visual studio code, I had to set this in /config/index.js. Change it in the:

module.exports = {
    dev: {
          // Paths
          assetsSubDirectory: 'static',
          assetsPublicPath: '/',
          proxyTable: {},

          host: 'localhost', // can be overwritten by process.env.HOST
          port: 8090, // can be overwritten by process.env.PORT, if port is in use, a free one will be determined
          autoOpenBrowser: false,
          errorOverlay: true,
          notifyOnErrors: true,
          poll: false    
         }
}

How to change a field name in JSON using Jackson

Jackson

If you are using Jackson, then you can use the @JsonProperty annotation to customize the name of a given JSON property.

Therefore, you just have to annotate the entity fields with the @JsonProperty annotation and provide a custom JSON property name, like this:

@Entity
public class City {

   @Id
   @JsonProperty("value")
   private Long id;

   @JsonProperty("label")
   private String name;

   //Getters and setters omitted for brevity
}

JavaEE or JakartaEE JSON-B

JSON-B is the standard binding layer for converting Java objects to and from JSON. If you are using JSON-B, then you can override the JSON property name via the @JsonbProperty annotation:

@Entity
public class City {

   @Id
   @JsonbProperty("value")
   private Long id;

   @JsonbProperty("label")
   private String name;

   //Getters and setters omitted for brevity
}

Split files using tar, gz, zip, or bzip2

If you are splitting from Linux, you can still reassemble in Windows.

copy /b file1 + file2 + file3 + file4 filetogether

How to disable a ts rule for a specific line?

You can use /* tslint:disable-next-line */ to locally disable tslint. However, as this is a compiler error disabling tslint might not help.

You can always temporarily cast $ to any:

delete ($ as any).summernote.options.keyMap.pc.TAB

which will allow you to access whatever properties you want.


Edit: As of Typescript 2.6, you can now bypass a compiler error/warning for a specific line:

if (false) {
    // @ts-ignore: Unreachable code error
    console.log("hello");
}

Note that the official docs "recommend you use [this] very sparingly". It is almost always preferable to cast to any instead as that better expresses intent.

BackgroundWorker vs background Thread

If it ain't broke - fix it till it is...just kidding :)

But seriously BackgroundWorker is probably very similar to what you already have, had you started with it from the beginning maybe you would have saved some time - but at this point I don't see the need. Unless something isn't working, or you think your current code is hard to understand, then I would stick with what you have.

tr:hover not working

Your best bet is to use

table.YourClass tr:hover td {
background-color: #FEFEFE;
}

Rows aren't fully support for background color but cells are, using the combination of :hover and the child element will yield the results you need.

php - How do I fix this illegal offset type error

Illegal offset type errors occur when you attempt to access an array index using an object or an array as the index key.

Example:

$x = new stdClass();
$arr = array();
echo $arr[$x];
//illegal offset type

Your $xml array contains an object or array at $xml->entry[$i]->source for some value of $i, and when you try to use that as an index key for $s, you get that warning. You'll have to make sure $xml contains what you want it to and that you're accessing it correctly.

Remove HTML Tags from an NSString on the iPhone

use this

NSString *myregex = @"<[^>]*>"; //regex to remove any html tag

NSString *htmlString = @"<html>bla bla</html>";
NSString *stringWithoutHTML = [hstmString stringByReplacingOccurrencesOfRegex:myregex withString:@""];

don't forget to include this in your code : #import "RegexKitLite.h" here is the link to download this API : http://regexkit.sourceforge.net/#Downloads

Could not install packages due to a "Environment error :[error 13]: permission denied : 'usr/local/bin/f2py'"

Well, in my case the problem had a different cause, the Windows path Length Check this.

I was installing a library on a virtualenv which made the path get longer. As the library was installed, it created some files under site-packages. This made the path exceed Windows limit throwing this error.

Hope it helps someone =)

Moving Git repository content to another repository preserving history

I am not very sure if what i did was right, but it worked anyways. I renamed repo2 folder present inside repo1, and committed the changes. In my case it was just one repo which i wanted to merge , so this approach worked. Later on, some path changes were done.

Reading from stdin

You can do something like this to read 10 bytes:

char buffer[10];
read(STDIN_FILENO, buffer, 10);

remember read() doesn't add '\0' to terminate to make it string (just gives raw buffer).

To read 1 byte at a time:

char ch;
while(read(STDIN_FILENO, &ch, 1) > 0)
{
 //do stuff
}

and don't forget to #include <unistd.h>, STDIN_FILENO defined as macro in this file.

There are three standard POSIX file descriptors, corresponding to the three standard streams, which presumably every process should expect to have:

Integer value   Name
       0        Standard input (stdin)
       1        Standard output (stdout)
       2        Standard error (stderr)

So instead STDIN_FILENO you can use 0.

Edit:
In Linux System you can find this using following command:

$ sudo grep 'STDIN_FILENO' /usr/include/* -R | grep 'define'
/usr/include/unistd.h:#define   STDIN_FILENO    0   /* Standard input.  */

Notice the comment /* Standard input. */

moving committed (but not pushed) changes to a new branch after pull

Here is a much simpler way:

  1. Create a new branch

  2. On your new branch do a git merge master- this will merge your committed (not pushed) changes to your new branch

  3. Delete you local master branch git branch -D master Use -D instead of -d because you want to force delete the branch.

  4. Just do a git fetch on your master branch and do a git pull on your master branch to ensure you have your teams latest code.

SQL Server: UPDATE a table by using ORDER BY

No.

Not a documented 100% supported way. There is an approach sometimes used for calculating running totals called "quirky update" that suggests that it might update in order of clustered index if certain conditions are met but as far as I know this relies completely on empirical observation rather than any guarantee.

But what version of SQL Server are you on? If SQL2005+ you might be able to do something with row_number and a CTE (You can update the CTE)

With cte As
(
SELECT id,Number,
ROW_NUMBER() OVER (ORDER BY id DESC) AS RN
FROM Test
)
UPDATE cte SET Number=RN

Reset par to the default values at startup

An alternative solution for preventing functions to change the user par. You can set the default parameters early on the function, so that the graphical parameters and layout will not be changed during the function execution. See ?on.exit for further details.

on.exit(layout(1))
opar<-par(no.readonly=TRUE)
on.exit(par(opar),add=TRUE,after=FALSE)

jQuery animate margin top

use 'marginTop' instead of MarginTop

$(this).find('.info').animate({ 'marginTop': '-50px', opacity: 0.5 }, 1000);

How to abort makefile if variable not set?

Use the shell function test:

foo:
    test $(something)

Usage:

$ make foo
test 
Makefile:2: recipe for target 'foo' failed
make: *** [foo] Error 1
$ make foo something=x
test x

How to trigger the window resize event in JavaScript?

You can do this with this library. https://github.com/itmor/events-js

const events = new Events();

events.add({  
  blockIsHidden: () =>  {
    if ($('div').css('display') === 'none') return true;
  }
});

function printText () {
  console.log('The block has become hidden!');
}

events.on('blockIsHidden', printText);

Convert datetime to valid JavaScript date

You can use moment.js for that, it will convert DateTime object into valid Javascript formated date:

   moment(DateOfBirth).format('DD-MMM-YYYY'); // put format as you want 

   Output: 28-Apr-1993

Hope it will help you :)

Sql error on update : The UPDATE statement conflicted with the FOREIGN KEY constraint

I guess if you change the id_no, some of the foreign keys would not reference anything, thus the constraint violation. You could add initialy deffered to the foreign keys, so the constraints are checked when the changes are commited

What's the difference between OpenID and OAuth?

OpenID and OAuth are each HTTP-based protocols for authentication and/or authorization. Both are intended to allow users to perform actions without giving authentication credentials or blanket permissions to clients or third parties. While they are similar, and there are proposed standards to use them both together, they are separate protocols.

OpenID is intended for federated authentication. A client accepts an identity assertion from any provider (although clients are free to whitelist or blacklist providers).

OAuth is intended for delegated authorization. A client registers with a provider, which provides authorization tokens which it will accept to perform actions on the user's behalf.

OAuth is currently better suited for authorization, because further interactions after authentication are built into the protocol, but both protocols are evolving. OpenID and its extensions could be used for authorization, and OAuth can be used for authentication, which can be thought of as a no-op authorization.

Generate a dummy-variable

If you want to get K dummy variables, instead of K-1, try:

dummies = table(1:length(year),as.factor(year))  

Best,

How do I declare a two dimensional array?

And I like this way:

$cars = array
  (
  array("Volvo",22),
  array("BMW",15),
  array("Saab",5),
  array("Land Rover",17)
  );

Nested jQuery.each() - continue/break

There are a lot of answers here. And it's old, but this is for anyone coming here via google. In jQuery each function

return false; is like break.

just

return; is like continue

These will emulate the behavior of break and continue.

How to change color of Android ListView separator line?

Use below code in your xml file

<ListView 
    android:id="@+id/listView"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:divider="#000000" 
    android:dividerHeight="1dp">
</ListView> 

Printing object properties in Powershell

The below worked really good for me. I patched together all the above answers plus read about displaying object properties in the following link and came up with the below short read about printing objects

add the following text to a file named print_object.ps1:

$date = New-Object System.DateTime
Write-Output $date | Get-Member
Write-Output $date | Select-Object -Property *

open powershell command prompt, go to the directory where that file exists and type the following:

powershell -ExecutionPolicy ByPass -File is_port_in_use.ps1 -Elevated

Just substitute 'System.DateTime' with whatever object you wanted to print. If the object is null, nothing will print out.

How to Code Double Quotes via HTML Codes

Google recommend that you don't use any of them, source.

There is no need to use entity references like &mdash, &rdquo, or &#x263a, assuming the same encoding (UTF-8) is used for files and editors as well as among teams.

Is there a reason you can't simply use "?

How to set min-font-size in CSS

CSS Solution:

.h2{
  font-size: 2vw
}
@media (min-width: 700px) {
  .h2{
    /* Minimum font size */
    font-size: 14px
  }
}
@media (max-width: 1200px) {
  .h2{
    /* Maximum font size */
    font-size: 24px
  }
}

Just in case if some need scss mixin:

///
/// Viewport sized typography with minimum and maximum values
///
/// @author Eduardo Boucas (@eduardoboucas)
///
/// @param {Number}   $responsive  - Viewport-based size
/// @param {Number}   $min         - Minimum font size (px)
/// @param {Number}   $max         - Maximum font size (px)
///                                  (optional)
/// @param {Number}   $fallback    - Fallback for viewport-
///                                  based units (optional)
///
/// @example scss - 5vw font size (with 50px fallback),
///                 minumum of 35px and maximum of 150px
///  @include responsive-font(5vw, 35px, 150px, 50px);
///

@mixin responsive-font($responsive, $min, $max: false, $fallback: false) {
  $responsive-unitless: $responsive / ($responsive - $responsive + 1);
  $dimension: if(unit($responsive) == 'vh', 'height', 'width');
  $min-breakpoint: $min / $responsive-unitless * 100;

  @media (max-#{$dimension}: #{$min-breakpoint}) {
    font-size: $min;
  }

  @if $max {
    $max-breakpoint: $max / $responsive-unitless * 100;

    @media (min-#{$dimension}: #{$max-breakpoint}) {
      font-size: $max;
    }
  }

  @if $fallback {
    font-size: $fallback;
  }

  font-size: $responsive;
}

Javascript extends class

Take a look at Simple JavaScript Inheritance and Inheritance Patterns in JavaScript.

The simplest method is probably functional inheritance but there are pros and cons.

How to change owner of PostgreSql database?

Frank Heikens answer will only update database ownership. Often, you also want to update ownership of contained objects (including tables). Starting with Postgres 8.2, REASSIGN OWNED is available to simplify this task.

IMPORTANT EDIT!

Never use REASSIGN OWNED when the original role is postgres, this could damage your entire DB instance. The command will update all objects with a new owner, including system resources (postgres0, postgres1, etc.)


First, connect to admin database and update DB ownership:

psql
postgres=# REASSIGN OWNED BY old_name TO new_name;

This is a global equivalent of ALTER DATABASE command provided in Frank's answer, but instead of updating a particular DB, it change ownership of all DBs owned by 'old_name'.

The next step is to update tables ownership for each database:

psql old_name_db
old_name_db=# REASSIGN OWNED BY old_name TO new_name;

This must be performed on each DB owned by 'old_name'. The command will update ownership of all tables in the DB.

CURRENT_TIMESTAMP in milliseconds

Easiest way I found to receive current time in milliseconds in MySql:

SELECT (UNIX_TIMESTAMP(NOW(3)) * 1000)

Since MySql 5.6.

How to find event listeners on a DOM node when debugging or from the JavaScript code?

Chrome, Firefox, Vivaldi and Safari support getEventListeners(domElement) in their Developer Tools console.

For majority of the debugging purposes, this could be used.

Below is a very good reference to use it: https://developers.google.com/web/tools/chrome-devtools/console/utilities#geteventlisteners

Using variables in Nginx location rules

A modified python version of @danack's PHP generate script. It generates all files & folders that live inside of build/ to the parent directory, replacing all {{placeholder}} matches. You need to cd into build/ before running the script.

File structure

build/
-- (files/folders you want to generate)
-- build.py

sites-available/...
sites-enabled/...
nginx.conf
...

build.py

import os, re

# Configurations
target = os.path.join('.', '..')
variables = {
  'placeholder': 'your replacement here'
}


# Loop files
def loop(cb, subdir=''):
  dir = os.path.join('.', subdir);

  for name in os.listdir(dir):
    file = os.path.join(dir, name)
    newsubdir = os.path.join(subdir, name)

    if name == 'build.py': continue
    if os.path.isdir(file): loop(cb, newsubdir)
    else: cb(subdir, name)


# Update file
def replacer(subdir, name):
  dir  = os.path.join(target, subdir)
  file = os.path.join(dir, name)
  oldfile = os.path.join('.', subdir, name)

  with open(oldfile, "r") as fin:
    data = fin.read()

  for key, replacement in variables.iteritems():
    data = re.sub(r"{{\s*" + key + "\s*}}", replacement, data)

  if not os.path.exists(dir):
    os.makedirs(dir)

  with open(file, "w") as fout:
    fout.write(data)


# Start variable replacements.
loop(replacer)

Getting values from JSON using Python

What error is it giving you?

If you do exactly this:

data = json.loads('{"lat":444, "lon":555}')

Then:

data['lat']

SHOULD NOT give you any error at all.

the MySQL service on local computer started and then stopped

If you came across this while installing WAMP64 on Windows 10. Check if data folder in MySQL folder is missing. My WAMP 3.2.3 version installation failed to create such a folder. So wamp icon was orange (1 of 2 services running).

A quick fix was to run this command from MySQL location.

C:\wamp64\bin\mysql\mysql5.7.31\bin\
mysqld --initialize-insecure

SET NOCOUNT ON usage

If you're saying you might have different clients as well, there are problems with classic ADO if SET NOCOUNT is not set ON.

One I experience regularly: if a stored procedure executes a number of statements (and thus a number of "xxx rows affected" messages are returned), ADO seems not to handle this and throws the error "Cannot change the ActiveConnection property of a Recordset object which has a Command object as its source."

So I generally advocate setting it ON unless there's a really really good reason not to. you may have found the really really good reason which I need to go and read into more.

Best JavaScript compressor

bananascript.com used to give me best results.

Android: keep Service running when app is killed

The reason for this is that you are trying to use an IntentService. Here is the line from the API Docs

The IntentService does the following:

Stops the service after all start requests have been handled, so you never have to call stopSelf().

Thus if you want your service to run indefinitely i suggest you extend the Service class instead. However this does not guarantee your service will run indefinitely. Your service will still have a chance of being killed by the kernel in a state of low memory if it is low priority.So you have two options:
1)Keep it running in the foreground by calling the startForeground() method.
2)Restart the service if it gets killed. Here is a part of the example from the docs where they talk about restarting the service after it is killed

 public int onStartCommand(Intent intent, int flags, int startId) {
      Toast.makeText(this, "service starting", Toast.LENGTH_SHORT).show();

      // For each start request, send a message to start a job and deliver the 
      // start ID so we know which request we're stopping when we finish the job 
      Message msg = mServiceHandler.obtainMessage();
      msg.arg1 = startId;
      mServiceHandler.sendMessage(msg);

      // If we get killed, after returning from here, restart 
      return START_STICKY;
  }  

Split string with multiple delimiters in Python

Luckily, Python has this built-in :)

import re
re.split('; |, ',str)

Update:
Following your comment:

>>> a='Beautiful, is; better*than\nugly'
>>> import re
>>> re.split('; |, |\*|\n',a)
['Beautiful', 'is', 'better', 'than', 'ugly']

jQuery, get ID of each element in a class using .each?

patrick dw's answer is right on.

For kicks and giggles I thought I would post a simple way to return an array of all the IDs.

var arrayOfIds = $.map($(".myClassName"), function(n, i){
  return n.id;
});
alert(arrayOfIds);

JavaScriptSerializer - JSON serialization of enum as string

Here is a simple solution that serializes a server-side C# enum to JSON and uses the result to populate a client-side <select> element. This works for both simple enums and bitflag enums.

I have included the end-to-end solution because I think most people wanting to serialize a C# enum to JSON will also probably be using it to fill a <select> drop-down.

Here goes:

Example Enum

public enum Role
{
    None = Permission.None,
    Guest = Permission.Browse,
    Reader = Permission.Browse| Permission.Help ,
    Manager = Permission.Browse | Permission.Help | Permission.Customise
}

A complex enum that uses bitwise ORs to generate a permissions system. So you can't rely on the simple index [0,1,2..] for the integer value of the enum.

Server Side - C#

Get["/roles"] = _ =>
{
    var type = typeof(Role);
    var data = Enum
        .GetNames(type)
        .Select(name => new 
            {
                Id = (int)Enum.Parse(type, name), 
                Name = name 
            })
        .ToArray();

    return Response.AsJson(data);
};

The code above uses the NancyFX framework to handle the Get request. It uses Nancy's Response.AsJson() helper method - but don't worry, you can use any standard JSON formatter as the enum has already been projected into a simple anonymous type ready for serialization.

Generated JSON

[
    {"Id":0,"Name":"None"},
    {"Id":2097155,"Name":"Guest"},
    {"Id":2916367,"Name":"Reader"},
    {"Id":4186095,"Name":"Manager"}
]

Client Side - CoffeeScript

fillSelect=(id, url, selectedValue=0)->
    $select = $ id
    $option = (item)-> $ "<option/>", 
        {
            value:"#{item.Id}"
            html:"#{item.Name}"
            selected:"selected" if item.Id is selectedValue
        }
    $.getJSON(url).done (data)->$option(item).appendTo $select for item in data

$ ->
    fillSelect "#role", "/roles", 2916367

HTML Before

<select id="role" name="role"></select>

HTML After

<select id="role" name="role">
    <option value="0">None</option>
    <option value="2097155">Guest</option>
    <option value="2916367" selected="selected">Reader</option>
    <option value="4186095">Manager</option>
</select>

How to set Spring profile from system variable?

If you provide your JVM the Spring profile there should be no problems:

java -Dspring.profiles.active=development -jar yourApplication.jar 

Also see Spring-Documentation:

http://docs.spring.io/spring-boot/docs/current/reference/html/howto-properties-and-configuration.html

69.5 Set the active Spring profiles

The Spring Environment has an API for this, but normally you would set a System property (spring.profiles.active) or an OS environment variable (SPRING_PROFILES_ACTIVE). E.g. launch your application with a -D argument (remember to put it before the main class or jar archive):

$ java -jar -Dspring.profiles.active=production demo-0.0.1-SNAPSHOT.jar

In Spring Boot you can also set the active profile in application.properties, e.g.

spring.profiles.active=production

A value set this way is replaced by the System property or environment variable setting, but not by the SpringApplicationBuilder.profiles() method. Thus the latter Java API can be used to augment the profiles without changing the defaults.

See Chapter 25, Profiles in the ‘Spring Boot features’ section for more information.

Send text to specific contact programmatically (whatsapp)

Use this function. Don't forget to save the WhatsApp Number on your mobile before sending trigger the function.

private void openWhatsApp() {
        Uri uri = Uri.parse("smsto:"+ "12345");
        Intent i = new Intent(Intent.ACTION_SENDTO,uri);
        i.setPackage("com.whatsapp");
        startActivity(i);
    }

Why do I get java.lang.AbstractMethodError when trying to load a blob in the db?

Just put ojdbc6.jar in class path, so that we can fix CallbaleStatement exception:

oracle.jdbc.driver.T4CPreparedStatement.setBinaryStream(ILjava/io/InputStream;J)V)

in Oracle.

"Conversion to Dalvik format failed with error 1" on external JAR

None of the answers here worked for me either.

However, I could fix the error by removing the Android classpath container (in my case Android 4.4) from ALL attached libraries except the main application and then exporting the APK. The library projects won't compile anymore, but the jar file still exists and the APK is getting deployed. I'm not sure what's the reason for this behaviour.

Using JSON POST Request

Modern browsers do not currently implement JSONRequest (as far as I know) since it is only a draft right now. I have found someone who has implemented it as a library that you can include in your page: http://devpro.it/JSON/files/JSONRequest-js.html (please note that it has a few dependencies).

Otherwise, you might want to go with another JS library like jQuery or Mootools.

NGinx Default public www location?

The default web folder for nginx depends on how you installed it, but normally it's in these locations:

/usr/local/nginx/html
/usr/nginx/html

Viewing full version tree in git

You can try the following:

gitk --all

You can tell gitk what to display using anything that git rev-list understands, so if you just want a few branches, you can do:

gitk master origin/master origin/experiment

... or more exotic things like:

gitk --simplify-by-decoration --all

Possible reasons for timeout when trying to access EC2 instance

For me it was the apache server hosted on a t2.micro linux EC2 instance, not the EC2 instance itself.

I fixed it by doing:

sudo su

service httpd restart

What exactly does an #if 0 ..... #endif block do?

It permanently comments out that code so the compiler will never compile it.

The coder can later change the #ifdef to have that code compile in the program if he wants to.

It's exactly like the code doesn't exist.

Getting a map() to return a list in Python 3.x

You can try getting a list from the map object by just iterating each item in the object and store it in a different variable.

a = map(chr, [66, 53, 0, 94])
b = [item for item in a]
print(b)
>>>['B', '5', '\x00', '^']

Xcopy Command excluding files and folders

Just give full path to exclusion file: eg..

-- no - - - - -xcopy c:\t1 c:\t2 /EXCLUDE:list-of-excluded-files.txt

correct - - - xcopy c:\t1 c:\t2 /EXCLUDE:C:\list-of-excluded-files.txt

In this example the file would be located " C:\list-of-excluded-files.txt "

or...

correct - - - xcopy c:\t1 c:\t2 /EXCLUDE:C:\mybatch\list-of-excluded-files.txt

In this example the file would be located " C:\mybatch\list-of-excluded-files.txt "

Full path fixes syntax error.

How to add local .jar file dependency to build.gradle file?

According to the documentation, use a relative path for a local jar dependency as follows:

dependencies {
    implementation files('libs/something_local.jar')
}

How to trace the path in a Breadth-First Search?

I liked qiao's first answer very much! The only thing missing here is to mark the vertexes as visited.

Why we need to do it?
Lets imagine that there is another node number 13 connected from node 11. Now our goal is to find node 13.
After a little bit of a run the queue will look like this:

[[1, 2, 6], [1, 3, 10], [1, 4, 7], [1, 4, 8], [1, 2, 5, 9], [1, 2, 5, 10]]

Note that there are TWO paths with node number 10 at the end.
Which means that the paths from node number 10 will be checked twice. In this case it doesn't look so bad because node number 10 doesn't have any children.. But it could be really bad (even here we will check that node twice for no reason..)
Node number 13 isn't in those paths so the program won't return before reaching to the second path with node number 10 at the end..And we will recheck it..

All we are missing is a set to mark the visited nodes and not to check them again..
This is qiao's code after the modification:

graph = {
    1: [2, 3, 4],
    2: [5, 6],
    3: [10],
    4: [7, 8],
    5: [9, 10],
    7: [11, 12],
    11: [13]
}


def bfs(graph_to_search, start, end):
    queue = [[start]]
    visited = set()

    while queue:
        # Gets the first path in the queue
        path = queue.pop(0)

        # Gets the last node in the path
        vertex = path[-1]

        # Checks if we got to the end
        if vertex == end:
            return path
        # We check if the current node is already in the visited nodes set in order not to recheck it
        elif vertex not in visited:
            # enumerate all adjacent nodes, construct a new path and push it into the queue
            for current_neighbour in graph_to_search.get(vertex, []):
                new_path = list(path)
                new_path.append(current_neighbour)
                queue.append(new_path)

            # Mark the vertex as visited
            visited.add(vertex)


print bfs(graph, 1, 13)

The output of the program will be:

[1, 4, 7, 11, 13]

Without the unneccecery rechecks..

pyplot scatter plot marker size

It is the area of the marker. I mean if you have s1 = 1000 and then s2 = 4000, the relation between the radius of each circle is: r_s2 = 2 * r_s1. See the following plot:

plt.scatter(2, 1, s=4000, c='r')
plt.scatter(2, 1, s=1000 ,c='b')
plt.scatter(2, 1, s=10, c='g')

enter image description here

I had the same doubt when I saw the post, so I did this example then I used a ruler on the screen to measure the radii.

show all tables in DB2 using the LIST command

To get a list of tables for the current database in DB2 -->

Connect to the database:

db2 connect to DATABASENAME user USER using PASSWORD

Run this query:

db2 LIST TABLES

This is the equivalent of SHOW TABLES in MySQL.

You may need to execute 'set schema myschema' to the correct schema before you run the list tables command. By default upon login your schema is the same as your username - which often won't contain any tables. You can use 'values current schema' to check what schema you're currently set to.

Using classes with the Arduino

I created this simple one a while back. The main challenge I had was to create a good build environment - a makefile that would compile and link/deploy everything without having to use the GUI. For the code, here is the header:

class AMLed
{
    private:
          uint8_t _ledPin;
          long _turnOffTime;

    public:
          AMLed(uint8_t pin);
          void setOn();
          void setOff();
          // Turn the led on for a given amount of time (relies
          // on a call to check() in the main loop()).
          void setOnForTime(int millis);
          void check();
};

And here is the main source

AMLed::AMLed(uint8_t ledPin) : _ledPin(ledPin), _turnOffTime(0)
{
    pinMode(_ledPin, OUTPUT);
}

void AMLed::setOn()
{
    digitalWrite(_ledPin, HIGH);
}

void AMLed::setOff()
{
    digitalWrite(_ledPin, LOW);
}

void AMLed::setOnForTime(int p_millis)
{
    _turnOffTime = millis() + p_millis;
    setOn();
}

void AMLed::check()
{
    if (_turnOffTime != 0 && (millis() > _turnOffTime))
    {
        _turnOffTime = 0;
        setOff();
    }
}

It's more prettily formatted here: http://amkimian.blogspot.com/2009/07/trivial-led-class.html

To use, I simply do something like this in the .pde file:

#include "AM_Led.h"

#define TIME_LED    12   // The port for the LED

AMLed test(TIME_LED);

How to check if an element exists in the xml using xpath?

take look at my example

<tocheading language="EN"> 
     <subj-group> 
         <subject>Editors Choice</subject> 
         <subject>creative common</subject> 
     </subj-group> 
</tocheading> 

now how to check if creative common is exist

tocheading/subj-group/subject/text() = 'creative common'

hope this help you

How do you debug PHP scripts?

PHP DBG

The Interactive Stepthrough PHP Debugger implemented as a SAPI module which can give give you complete control over the environment without impacting the functionality or performance of your code. It aims to be a lightweight, powerful, easy to use debugging platform for PHP 5.4+ and it's shipped out-of-box with PHP 5.6.

Features includes:

  • Stepthrough Debugging
  • Flexible Breakpoints (Class Method, Function, File:Line, Address, Opcode)
  • Easy Access to PHP with built-in eval()
  • Easy Access to Currently Executing Code
  • Userland API
  • SAPI Agnostic - Easily Integrated
  • PHP Configuration File Support
  • JIT Super Globals - Set Your Own!!
  • Optional readline Support - Comfortable Terminal Operation
  • Remote Debugging Support - Bundled Java GUI
  • Easy Operation

See the screenshots:

PHP DBG - Stepthrough Debugging - screenshot

PHP DBG - Stepthrough Debugging - screenshot

Home page: http://phpdbg.com/

PHP Error - Better error reporting for PHP

This is very easy to use library (actually a file) to debug your PHP scripts.

The only thing that you need to do is to include one file as below (at the beginning on your code):

require('php_error.php');
\php_error\reportErrors();

Then all errors will give you info such as backtrace, code context, function arguments, server variables, etc. For example:

PHP Error | Improve Error Reporting for PHP - screenshot of backtrace PHP Error | Improve Error Reporting for PHP - screenshot of backtrace PHP Error | Improve Error Reporting for PHP - screenshot of backtrace

Features include:

  • trivial to use, it's just one file
  • errors displayed in the browser for normal and ajaxy requests
  • AJAX requests are paused, allowing you to automatically re-run them
  • makes errors as strict as possible (encourages code quality, and tends to improve performance)
  • code snippets across the whole stack trace
  • provides more information (such as full function signatures)
  • fixes some error messages which are just plain wrong
  • syntax highlighting
  • looks pretty!
  • customization
  • manually turn it on and off
  • run specific sections without error reporting
  • ignore files allowing you to avoid highlighting code in your stack trace
  • application files; these are prioritized when an error strikes!

Home page: http://phperror.net/

GitHub: https://github.com/JosephLenton/PHP-Error

My fork (with extra fixes): https://github.com/kenorb-contrib/PHP-Error

DTrace

If your system supports DTrace dynamic tracing (installed by default on OS X) and your PHP is compiled with the DTrace probes enabled (--enable-dtrace) which should be by default, this command can help you to debug PHP script with no time:

sudo dtrace -qn 'php*:::function-entry { printf("%Y: PHP function-entry:\t%s%s%s() in %s:%d\n", walltimestamp, copyinstr(arg3), copyinstr(arg4), copyinstr(arg0), basename(copyinstr(arg1)), (int)arg2); }'

So given the following alias has been added into your rc files (e.g. ~/.bashrc, ~/.bash_aliases):

alias trace-php='sudo dtrace -qn "php*:::function-entry { printf(\"%Y: PHP function-entry:\t%s%s%s() in %s:%d\n\", walltimestamp, copyinstr(arg3), copyinstr(arg4), copyinstr(arg0), basename(copyinstr(arg1)), (int)arg2); }"'

you may trace your script with easy to remember alias: trace-php.

Here is more advanced dtrace script, just save it into dtruss-php.d, make it executable (chmod +x dtruss-php.d) and run:

#!/usr/sbin/dtrace -Zs
# See: https://github.com/kenorb/dtruss-lamp/blob/master/dtruss-php.d

#pragma D option quiet

php*:::compile-file-entry
{
    printf("%Y: PHP compile-file-entry:\t%s (%s)\n", walltimestamp, basename(copyinstr(arg0)), copyinstr(arg1));
}

php*:::compile-file-return
{
    printf("%Y: PHP compile-file-return:\t%s (%s)\n", walltimestamp, basename(copyinstr(arg0)), basename(copyinstr(arg1)));
}

php*:::error
{
    printf("%Y: PHP error message:\t%s in %s:%d\n", walltimestamp, copyinstr(arg0), basename(copyinstr(arg1)), (int)arg2);
}

php*:::exception-caught
{
    printf("%Y: PHP exception-caught:\t%s\n", walltimestamp, copyinstr(arg0));
}

php*:::exception-thrown
{
    printf("%Y: PHP exception-thrown:\t%s\n", walltimestamp, copyinstr(arg0));
}

php*:::execute-entry
{
    printf("%Y: PHP execute-entry:\t%s:%d\n", walltimestamp, basename(copyinstr(arg0)), (int)arg1);
}

php*:::execute-return
{
    printf("%Y: PHP execute-return:\t%s:%d\n", walltimestamp, basename(copyinstr(arg0)), (int)arg1);
}

php*:::function-entry
{
    printf("%Y: PHP function-entry:\t%s%s%s() in %s:%d\n", walltimestamp, copyinstr(arg3), copyinstr(arg4), copyinstr(arg0), basename(copyinstr(arg1)), (int)arg2);
}

php*:::function-return
{
    printf("%Y: PHP function-return:\t%s%s%s() in %s:%d\n", walltimestamp, copyinstr(arg3), copyinstr(arg4), copyinstr(arg0), basename(copyinstr(arg1)), (int)arg2);
}

php*:::request-shutdown
{
    printf("%Y: PHP request-shutdown:\t%s at %s via %s\n", walltimestamp, basename(copyinstr(arg0)), copyinstr(arg1), copyinstr(arg2));
}

php*:::request-startup
{
    printf("%Y, PHP request-startup:\t%s at %s via %s\n", walltimestamp, basename(copyinstr(arg0)), copyinstr(arg1), copyinstr(arg2));
}

Home page: dtruss-lamp at GitHub

Here is simple usage:

  1. Run: sudo dtruss-php.d.
  2. On another terminal run: php -r "phpinfo();".

To test that, you can go to any docroot with index.php and run PHP builtin server by:

php -S localhost:8080

After that you can access the site at http://localhost:8080/ (or choose whatever port is convenient for you). From there access some pages to see the trace output.

Note: Dtrace is available on OS X by default, on Linux you probably need dtrace4linux or check for some other alternatives.

See: Using PHP and DTrace at php.net


SystemTap

Alternatively check for SystemTap tracing by installing SystemTap SDT development package (e.g. yum install systemtap-sdt-devel).

Here is example script (all_probes.stp) for tracing all core PHP static probe points throughout the duration of a running PHP script with SystemTap:

probe process("sapi/cli/php").provider("php").mark("compile__file__entry") {
    printf("Probe compile__file__entry\n");
    printf("  compile_file %s\n", user_string($arg1));
    printf("  compile_file_translated %s\n", user_string($arg2));
}
probe process("sapi/cli/php").provider("php").mark("compile__file__return") {
    printf("Probe compile__file__return\n");
    printf("  compile_file %s\n", user_string($arg1));
    printf("  compile_file_translated %s\n", user_string($arg2));
}
probe process("sapi/cli/php").provider("php").mark("error") {
    printf("Probe error\n");
    printf("  errormsg %s\n", user_string($arg1));
    printf("  request_file %s\n", user_string($arg2));
    printf("  lineno %d\n", $arg3);
}
probe process("sapi/cli/php").provider("php").mark("exception__caught") {
    printf("Probe exception__caught\n");
    printf("  classname %s\n", user_string($arg1));
}
probe process("sapi/cli/php").provider("php").mark("exception__thrown") {
    printf("Probe exception__thrown\n");
    printf("  classname %s\n", user_string($arg1));
}
probe process("sapi/cli/php").provider("php").mark("execute__entry") {
    printf("Probe execute__entry\n");
    printf("  request_file %s\n", user_string($arg1));
    printf("  lineno %d\n", $arg2);
}
probe process("sapi/cli/php").provider("php").mark("execute__return") {
    printf("Probe execute__return\n");
    printf("  request_file %s\n", user_string($arg1));
    printf("  lineno %d\n", $arg2);
}
probe process("sapi/cli/php").provider("php").mark("function__entry") {
    printf("Probe function__entry\n");
    printf("  function_name %s\n", user_string($arg1));
    printf("  request_file %s\n", user_string($arg2));
    printf("  lineno %d\n", $arg3);
    printf("  classname %s\n", user_string($arg4));
    printf("  scope %s\n", user_string($arg5));
}
probe process("sapi/cli/php").provider("php").mark("function__return") {
    printf("Probe function__return: %s\n", user_string($arg1));
    printf(" function_name %s\n", user_string($arg1));
    printf("  request_file %s\n", user_string($arg2));
    printf("  lineno %d\n", $arg3);
    printf("  classname %s\n", user_string($arg4));
    printf("  scope %s\n", user_string($arg5));
}
probe process("sapi/cli/php").provider("php").mark("request__shutdown") {
    printf("Probe request__shutdown\n");
    printf("  file %s\n", user_string($arg1));
    printf("  request_uri %s\n", user_string($arg2));
    printf("  request_method %s\n", user_string($arg3));
}
probe process("sapi/cli/php").provider("php").mark("request__startup") {
    printf("Probe request__startup\n");
    printf("  file %s\n", user_string($arg1));
    printf("  request_uri %s\n", user_string($arg2));
    printf("  request_method %s\n", user_string($arg3));
}

Usage:

stap -c 'sapi/cli/php test.php' all_probes.stp

See: Using SystemTap with PHP DTrace Static Probes at php.net

Flask - Calling python function on button OnClick event

index.html (index.html should be in templates folder)

<!doctype html>
<html>

<head>
    <title>The jQuery Example</title>

    <h2>jQuery-AJAX in FLASK. Execute function on button click</h2>  

    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"> </script>
    <script type=text/javascript> $(function() { $("#mybutton").click(function (event) { $.getJSON('/SomeFunction', { },
    function(data) { }); return false; }); }); </script> 
</head>

<body>        
        <input type = "button" id = "mybutton" value = "Click Here" />
</body>    

</html>

test.py

from flask import Flask, jsonify, render_template, request
app = Flask(__name__)


@app.route('/')
def index():
    return render_template('index.html')

@app.route('/SomeFunction')
def SomeFunction():
    print('In SomeFunction')
    return "Nothing"



if __name__ == '__main__':
   app.run()

Operation must use an updatable query. (Error 3073) Microsoft Access

The problem defintely relates to the use of (in this case) the max() function. Any aggregation function used during a join (e.g. to retrieve the max or min or avg value from a joined table) will cause the error. And the same applies to using subqueries instead of joins (as in the original code).

This is incredibly annoying (and unjustified!) as it is a reasonably common thing to want to do. I've also had to use temp tables to get around it (pull the aggregated value into a temp table with an insert statement, then join to this table with your update, then drop the temp table).

Glenn

Get file size, image width and height before upload

If you can use the jQuery validation plugin you can do it like so:

Html:

<input type="file" name="photo" id="photoInput" />

JavaScript:

$.validator.addMethod('imagedim', function(value, element, param) {
  var _URL = window.URL;
        var  img;
        if ((element = this.files[0])) {
            img = new Image();
            img.onload = function () {
                console.log("Width:" + this.width + "   Height: " + this.height);//this will give you image width and height and you can easily validate here....

                return this.width >= param
            };
            img.src = _URL.createObjectURL(element);
        }
});

The function is passed as ab onload function.

The code is taken from here

jQuery & CSS - Remove/Add display:none

The only way to remove an inline "display:none" via jQuery's css-api is by resetting it with the empty string (null does NOT work btw!!).

According to the jQuery docu this is the general way to "remove" a once set inline style property.

$("#mydiv").css("display","");

or

$("#mydiv").css({display:""});

should do the trick properly.

IMHO there is a method missing in jQuery that could be called "unhide" or "reveal" which instead of just setting another inline style property unsets the display value properly as described above. Or maybe hide() should store the initial inline value and show() should restore that...

'react-scripts' is not recognized as an internal or external command

In my situation, some problems happened with my node package. So I run npm audit fix and it fixed all problems

How do I get Month and Date of JavaScript in 2 digit format?

Just another example, almost one liner.

_x000D_
_x000D_
var date = new Date();_x000D_
console.log( (date.getMonth() < 9 ? '0': '') + (date.getMonth()+1) );
_x000D_
_x000D_
_x000D_

Remove padding or margins from Google Charts

There is this possibility like Aman Virk mentioned:

var options = {
    chartArea:{left:10,top:20,width:"100%",height:"100%"}
};

But keep in mind that the padding and margin aren't there to bother you. If you have the possibility to switch between different types of charts like a ColumnChart and the one with vertical columns then you need some margin for displaying the labels of those lines.

If you take away that margin then you will end up showing only a part of the labels or no labels at all.

So if you just have one chart type then you can change the margin and padding like Arman said. But if it's possible to switch don't change them.

How to create war files

If you are not sure what to do and are starting from scratch then Maven can help get you started.

By following the the below steps you can get a new war project setup perfectly in eclipse.

  1. Download and install Maven
  2. Go the command line run: mvn archetype:generate
  3. Follow the prompted steps - choosing the simple java web project (18) and a suitable name.
  4. When it is finished run: mvn eclipse:eclipse
  5. Start Eclipse. Choose File -> Import -> Existing project. Select the directory where you ran the mvn goals.
  6. That's it you should now have a very good start to a war project in eclipse
  7. You can create the war itself by running mvn package or deploy it by setting up a server in eclipse and simply adding adding the project to the server.

As some others have said the downside of using maven is that you have to use the maven conventions. But I think if you are just starting out, learning the conventions is a good idea before you start making your own. There's nothing to stop you changing/refactoring to your own preferred method at a later point.

Hope this helps.

Laravel 5 call a model function in a blade view

want to use model in view as:

{{ Product::find($id) }}

you can use in view:

<?php
$tmp = \App\Product::find($id);
?>
{{ $tmp->name }}

Hope this will help you

Combine two data frames by rows (rbind) when they have different sets of columns

I wrote a function to do this because I like my code to tell me if something is wrong. This function will explicitly tell you which column names don't match and if you have a type mismatch. Then it will do its best to combine the data.frames anyway. The limitation is that you can only combine two data.frames at a time.

### combines data frames (like rbind) but by matching column names
# columns without matches in the other data frame are still combined
# but with NA in the rows corresponding to the data frame without
# the variable
# A warning is issued if there is a type mismatch between columns of
# the same name and an attempt is made to combine the columns
combineByName <- function(A,B) {
    a.names <- names(A)
    b.names <- names(B)
    all.names <- union(a.names,b.names)
    print(paste("Number of columns:",length(all.names)))
    a.type <- NULL
    for (i in 1:ncol(A)) {
        a.type[i] <- typeof(A[,i])
    }
    b.type <- NULL
    for (i in 1:ncol(B)) {
        b.type[i] <- typeof(B[,i])
    }
    a_b.names <- names(A)[!names(A)%in%names(B)]
    b_a.names <- names(B)[!names(B)%in%names(A)]
    if (length(a_b.names)>0 | length(b_a.names)>0){
        print("Columns in data frame A but not in data frame B:")
        print(a_b.names)
        print("Columns in data frame B but not in data frame A:")
        print(b_a.names)
    } else if(a.names==b.names & a.type==b.type){
        C <- rbind(A,B)
        return(C)
    }
    C <- list()
    for(i in 1:length(all.names)) {
        l.a <- all.names[i]%in%a.names
        pos.a <- match(all.names[i],a.names)
        typ.a <- a.type[pos.a]
        l.b <- all.names[i]%in%b.names
        pos.b <- match(all.names[i],b.names)
        typ.b <- b.type[pos.b]
        if(l.a & l.b) {
            if(typ.a==typ.b) {
                vec <- c(A[,pos.a],B[,pos.b])
            } else {
                warning(c("Type mismatch in variable named: ",all.names[i],"\n"))
                vec <- try(c(A[,pos.a],B[,pos.b]))
            }
        } else if (l.a) {
            vec <- c(A[,pos.a],rep(NA,nrow(B)))
        } else {
            vec <- c(rep(NA,nrow(A)),B[,pos.b])
        }
        C[[i]] <- vec
    }
    names(C) <- all.names
    C <- as.data.frame(C)
    return(C)
}

@Autowired - No qualifying bean of type found for dependency

I was facing the same issue while auto-wiring the class from one of my jar file. I fixed the issue by using @Lazy annotation:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Lazy;

    @Autowired
    @Lazy
    private IGalaxyCommand iGalaxyCommand;

Check if property has attribute

You can use the Attribute.IsDefined method

https://msdn.microsoft.com/en-us/library/system.attribute.isdefined(v=vs.110).aspx

if(Attribute.IsDefined(YourProperty,typeof(YourAttribute)))
{
    //Conditional execution...
}

You could provide the property you're specifically looking for or you could iterate through all of them using reflection, something like:

PropertyInfo[] props = typeof(YourClass).GetProperties();

Display text from .txt file in batch file

@echo off
set log=%time% %date%
echo %log%

That is a batch for saving the date and time as a temporary variable, and displaying it. In a hurry, I don't have time to write a script to open a txt, maybe later.

Calling Objective-C method from C++ member function?

You can mix C++ with Objective-C if you do it carefully. There are a few caveats but generally speaking they can be mixed. If you want to keep them separate, you can set up a standard C wrapper function that gives the Objective-C object a usable C-style interface from non-Objective-C code (pick better names for your files, I have picked these names for verbosity):

MyObject-C-Interface.h

#ifndef __MYOBJECT_C_INTERFACE_H__
#define __MYOBJECT_C_INTERFACE_H__

// This is the C "trampoline" function that will be used
// to invoke a specific Objective-C method FROM C++
int MyObjectDoSomethingWith (void *myObjectInstance, void *parameter);
#endif

MyObject.h

#import "MyObject-C-Interface.h"

// An Objective-C class that needs to be accessed from C++
@interface MyObject : NSObject
{
    int someVar;
}

// The Objective-C member function you want to call from C++
- (int) doSomethingWith:(void *) aParameter;
@end

MyObject.mm

#import "MyObject.h"

@implementation MyObject

// C "trampoline" function to invoke Objective-C method
int MyObjectDoSomethingWith (void *self, void *aParameter)
{
    // Call the Objective-C method using Objective-C syntax
    return [(id) self doSomethingWith:aParameter];
}

- (int) doSomethingWith:(void *) aParameter
{
    // The Objective-C function you wanted to call from C++.
    // do work here..
    return 21 ; // half of 42
}
@end

MyCPPClass.cpp

#include "MyCPPClass.h"
#include "MyObject-C-Interface.h"

int MyCPPClass::someMethod (void *objectiveCObject, void *aParameter)
{
    // To invoke an Objective-C method from C++, use
    // the C trampoline function
    return MyObjectDoSomethingWith (objectiveCObject, aParameter);
}

The wrapper function does not need to be in the same .m file as the Objective-C class, but the file that it does exist in needs to be compiled as Objective-C code. The header that declares the wrapper function needs to be included in both CPP and Objective-C code.

(NOTE: if the Objective-C implementation file is given the extension ".m" it will not link under Xcode. The ".mm" extension tells Xcode to expect a combination of Objective-C and C++, i.e., Objective-C++.)


You can implement the above in an Object-Orientented manner by using the PIMPL idiom. The implementation is only slightly different. In short, you place the wrapper functions (declared in "MyObject-C-Interface.h") inside a class with a (private) void pointer to an instance of MyClass.

MyObject-C-Interface.h (PIMPL)

#ifndef __MYOBJECT_C_INTERFACE_H__
#define __MYOBJECT_C_INTERFACE_H__

class MyClassImpl
{
public:
    MyClassImpl ( void );
    ~MyClassImpl( void );

    void init( void );
    int  doSomethingWith( void * aParameter );
    void logMyMessage( char * aCStr );

private:
    void * self;
};

#endif

Notice the wrapper methods no longer require the void pointer to an instance of MyClass; it is now a private member of MyClassImpl. The init method is used to instantiate a MyClass instance;

MyObject.h (PIMPL)

#import "MyObject-C-Interface.h"

@interface MyObject : NSObject
{
    int someVar;
}

- (int)  doSomethingWith:(void *) aParameter;
- (void) logMyMessage:(char *) aCStr;

@end

MyObject.mm (PIMPL)

#import "MyObject.h"

@implementation MyObject

MyClassImpl::MyClassImpl( void )
    : self( NULL )
{   }

MyClassImpl::~MyClassImpl( void )
{
    [(id)self dealloc];
}

void MyClassImpl::init( void )
{    
    self = [[MyObject alloc] init];
}

int MyClassImpl::doSomethingWith( void *aParameter )
{
    return [(id)self doSomethingWith:aParameter];
}

void MyClassImpl::logMyMessage( char *aCStr )
{
    [(id)self doLogMessage:aCStr];
}

- (int) doSomethingWith:(void *) aParameter
{
    int result;

    // ... some code to calculate the result

    return result;
}

- (void) logMyMessage:(char *) aCStr
{
    NSLog( aCStr );
}

@end

Notice that MyClass is instantiated with a call to MyClassImpl::init. You could instantiate MyClass in MyClassImpl's constructor, but that generally isn't a good idea. The MyClass instance is destructed from MyClassImpl's destructor. As with the C-style implementation, the wrapper methods simply defer to the respective methods of MyClass.

MyCPPClass.h (PIMPL)

#ifndef __MYCPP_CLASS_H__
#define __MYCPP_CLASS_H__

class MyClassImpl;

class MyCPPClass
{
    enum { cANSWER_TO_LIFE_THE_UNIVERSE_AND_EVERYTHING = 42 };
public:
    MyCPPClass ( void );
    ~MyCPPClass( void );

    void init( void );
    void doSomethingWithMyClass( void );

private:
    MyClassImpl * _impl;
    int           _myValue;
};

#endif

MyCPPClass.cpp (PIMPL)

#include "MyCPPClass.h"
#include "MyObject-C-Interface.h"

MyCPPClass::MyCPPClass( void )
    : _impl ( NULL )
{   }

void MyCPPClass::init( void )
{
    _impl = new MyClassImpl();
}

MyCPPClass::~MyCPPClass( void )
{
    if ( _impl ) { delete _impl; _impl = NULL; }
}

void MyCPPClass::doSomethingWithMyClass( void )
{
    int result = _impl->doSomethingWith( _myValue );
    if ( result == cANSWER_TO_LIFE_THE_UNIVERSE_AND_EVERYTHING )
    {
        _impl->logMyMessage( "Hello, Arthur!" );
    }
    else
    {
        _impl->logMyMessage( "Don't worry." );
    }
}

You now access calls to MyClass through a private implementation of MyClassImpl. This approach can be advantageous if you were developing a portable application; you could simply swap out the implementation of MyClass with one specific to the other platform ... but honestly, whether this is a better implementation is more a matter of taste and needs.