Programs & Examples On #Nssplitview

An NSSplitView object stacks several subviews within one view so that the user can change their relative sizes. By default, the split bars between the views are horizontal, so the views are one on top of the other.

Passing multiple parameters with $.ajax url

Why are you combining GET and POST? Use one or the other.

$.ajax({
    type: 'post',
    data: {
        timestamp: timestamp,
        uid: uid
        ...
    }
});

php:

$uid =$_POST['uid'];

Or, just format your request properly (you're missing the ampersands for the get parameters).

url:"getdata.php?timestamp="+timestamp+"&uid="+id+"&uname="+name,

How to save a data.frame in R?

There are several ways. One way is to use save() to save the exact object. e.g. for data frame foo:

save(foo,file="data.Rda")

Then load it with:

load("data.Rda")

You could also use write.table() or something like that to save the table in plain text, or dput() to obtain R code to reproduce the table.

How to pipe list of files returned by find command to cat to view all the files

There are a few ways to pass the list of files returned by the find command to the cat command, though technically not all use piping, and none actually pipe directly to cat.

  1. The simplest is to use backticks (`):

    cat `find [whatever]`
    

    This takes the output of find and effectively places it on the command line of cat. This doesn't work well if find has too much output (more than can fit on a command-line) or if the output has special characters (like spaces).

  2. In some shells, including bash, one can use $() instead of backticks :

    cat $(find [whatever])
    

    This is less portable, but is nestable. Aside from that, it has pretty much the same caveats as backticks.

  3. Because running other commands on what was found is a common use for find, find has an -exec action which executes a command for each file it finds:

    find [whatever] -exec cat {} \;
    

    The {} is a placeholder for the filename, and the \; marks the end of the command (It's possible to have other actions after -exec.)

    This will run cat once for every single file rather than running a single instance of cat passing it multiple filenames which can be inefficient and might not have the behavior you want for some commands (though it's fine for cat). The syntax is also a awkward to type -- you need to escape the semicolon because semicolon is special to the shell!

  4. Some versions of find (most notably the GNU version) let you replace ; with + to use -exec's append mode to run fewer instances of cat:

    find [whatever] -exec cat {} +
    

    This will pass multiple filenames to each invocation of cat, which can be more efficient.

    Note that this is not guaranteed to use a single invocation, however. If the command line would be too long then the arguments are spread across multiple invocations of cat. For cat this is probably not a big deal, but for some other commands this may change the behavior in undesirable ways. On Linux systems, the command line length limit is quite large, so splitting into multiple invocations is quite rare compared to some other OSes.

  5. The classic/portable approach is to use xargs:

    find [whatever] | xargs cat
    

    xargs runs the command specified (cat, in this case), and adds arguments based on what it reads from stdin. Just like -exec with +, this will break up the command-line if necessary. That is, if find produces too much output, it'll run cat multiple times. As mentioned in the section about -exec earlier, there are some commands where this splitting may result in different behavior. Note that using xargs like this has issues with spaces in filenames, as xargs just uses whitespace as a delimiter.

  6. The most robust, portable, and efficient method also uses xargs:

    find [whatever] -print0 | xargs -0 cat
    

    The -print0 flag tells find to use \0 (null character) delimiters between filenames, and the -0 flag tells xargs to expect these \0 delimiters. This has pretty much identical behavior to the -exec...+ approach, though is more portable (but unfortunately more verbose).

How to change Jquery UI Slider handle

.ui-slider .ui-slider-handle{
    width:50px; 
    height:50px; 
    background:url(../images/slider_grabber.png) no-repeat; overflow: hidden; 
    position:absolute;
    top: -10px;
    border-style:none; 
}

cmake and libpthread

@Manuel was part way there. You can add the compiler option as well, like this:

If you have CMake 3.1.0+, this becomes even easier:

set(THREADS_PREFER_PTHREAD_FLAG ON)
find_package(Threads REQUIRED)
target_link_libraries(my_app PRIVATE Threads::Threads)

If you are using CMake 2.8.12+, you can simplify this to:

find_package(Threads REQUIRED)
if(THREADS_HAVE_PTHREAD_ARG)
  target_compile_options(my_app PUBLIC "-pthread")
endif()
if(CMAKE_THREAD_LIBS_INIT)
  target_link_libraries(my_app "${CMAKE_THREAD_LIBS_INIT}")
endif()

Older CMake versions may require:

find_package(Threads REQUIRED)
if(THREADS_HAVE_PTHREAD_ARG)
  set_property(TARGET my_app PROPERTY COMPILE_OPTIONS "-pthread")
  set_property(TARGET my_app PROPERTY INTERFACE_COMPILE_OPTIONS "-pthread")
endif()
if(CMAKE_THREAD_LIBS_INIT)
  target_link_libraries(my_app "${CMAKE_THREAD_LIBS_INIT}")
endif()

If you want to use one of the first two methods with CMake 3.1+, you will need set(THREADS_PREFER_PTHREAD_FLAG ON) there too.

Input button target="_blank" isn't causing the link to load in a new window/tab

The formtarget attribute is only used for buttons with type="submit".

That is from this reference.

Here is an answer using JavaScript:

<input type="button" onClick="openNewTab()" value="facebook">

<script type="text/javascript">
    function openNewTab() {
        window.open("http://www.facebook.com/");
    }
</script>

How to make asynchronous HTTP requests in PHP

Symfony HttpClient is asynchronous https://symfony.com/doc/current/components/http_client.html.

For example you can

use Symfony\Component\HttpClient\HttpClient;

$client = HttpClient::create();
$response1 = $client->request('GET', 'https://website1');
$response2 = $client->request('GET', 'https://website1');
$response3 = $client->request('GET', 'https://website1');
//these 3 calls with return immediately
//but the requests will fire to the website1 webserver

$response1->getContent(); //this will block until content is fetched
$response2->getContent(); //same 
$response3->getContent(); //same

Round button with text and icon in flutter

You can simply use named constructors for creating different types of buttons with icons. For instance

FlatButton.icon(onPressed: null, icon: null, label: null);
RaisedButton.icon(onPressed: null, icon: null, label: null);

But if you have specfic requirements then you can always create custom button with different layouts or simply wrap a widget in GestureDetector.

SQL - IF EXISTS UPDATE ELSE INSERT INTO

Try this:

INSERT INTO `center_course_fee` (`fk_course_id`,`fk_center_code`,`course_fee`) VALUES ('69', '4920153', '6000') ON DUPLICATE KEY UPDATE `course_fee` = '6000';

Is there a simple way to convert C++ enum to string?

A problem with answer 0 is that the enum binary values do not necessarily start at 0 and are not necessarily contiguous.

When I need this, I usually:

  • pull the enum definition into my source
  • edit it to get just the names
  • do a macro to change the name to the case clause in the question, though typically on one line: case foo: return "foo";
  • add the switch, default and other syntax to make it legal

Adding a new line/break tag in XML

The Way to do Line Break in XML is to use &#xA;

It worked for me in Eclipse IDE , when I was designing my XML layout & was using TextView.

How to use switch statement inside a React component?

I really liked the suggestion in https://stackoverflow.com/a/60313570/770134, so I adapted it to Typescript like so

import React, { FunctionComponent } from 'react'
import { Optional } from "typescript-optional";
const { ofNullable } = Optional

interface SwitchProps {
  test: string
  defaultComponent: JSX.Element
}

export const Switch: FunctionComponent<SwitchProps> = (props) => {
  return ofNullable(props.children)
    .map((children) => {
      return ofNullable((children as JSX.Element[]).find((child) => child.props['value'] === props.test))
        .orElse(props.defaultComponent)
    })
    .orElseThrow(() => new Error('Children are required for a switch component'))
}

const Foo = ({ value = "foo" }) => <div>foo</div>;
const Bar = ({ value = "bar" }) => <div>bar</div>;
const value = "foo";
const SwitchExample = <Switch test={value} defaultComponent={<div />}>
  <Foo />
  <Bar />
</Switch>;

Angular 2 ngfor first, last, index loop

Here is how its done in Angular 6

<li *ngFor="let user of userObservable ; first as isFirst">
   <span *ngIf="isFirst">default</span>
</li>

Note the change from let first = first to first as isFirst

How to avoid mysql 'Deadlock found when trying to get lock; try restarting transaction'

I have a method, the internals of which are wrapped in a MySqlTransaction.

The deadlock issue showed up for me when I ran the same method in parallel with itself.

There was not an issue running a single instance of the method.

When I removed MySqlTransaction, I was able to run the method in parallel with itself with no issues.

Just sharing my experience, I'm not advocating anything.

Add new row to dataframe, at specific row-index, not appended?

The .before argument in dplyr::add_row can be used to specify the row.

dplyr::add_row(
  cars,
  speed = 0,
  dist = 0,
  .before = 3
)
#>    speed dist
#> 1      4    2
#> 2      4   10
#> 3      0    0
#> 4      7    4
#> 5      7   22
#> 6      8   16
#> ...

Difference between abstract class and interface in Python

In a more basic way to explain: An interface is sort of like an empty muffin pan. It's a class file with a set of method definitions that have no code.

An abstract class is the same thing, but not all functions need to be empty. Some can have code. It's not strictly empty.

Why differentiate: There's not much practical difference in Python, but on the planning level for a large project, it could be more common to talk about interfaces, since there's no code. Especially if you're working with Java programmers who are accustomed to the term.

How can I customize the tab-to-space conversion factor?

That is lonefy.vscode-js-css-html-formatter to blame. Disable it, and install HookyQR.beautify.

Now on save your tabs wouldn't be converted.

SQL SERVER, SELECT statement with auto generate row id

Select (Select count(y.au_lname) from dbo.authors y
where y.au_lname + y.au_fname <= x.au_lname + y.au_fname) as Counterid,
x.au_lname,x.au_fname from authors x group by au_lname,au_fname
order by Counterid --Alternatively that can be done which is equivalent as above..

Skip first entry in for loop in python?

I do it like this, even though it looks like a hack it works every time:

ls_of_things = ['apple', 'car', 'truck', 'bike', 'banana']
first = 0
last = len(ls_of_things)
for items in ls_of_things:
    if first == 0
        first = first + 1
        pass
    elif first == last - 1:
        break
    else:
        do_stuff
        first = first + 1
        pass

How to recursively find the latest modified file in a directory?

I had the trouble to find the last modified file under Solaris 10. There find does not have the printf option and stat is not available. I discovered the following solution which works well for me:

find . -type f | sed 's/.*/"&"/' | xargs ls -E | awk '{ print $6," ",$7 }' | sort | tail -1

To show the filename as well use

find . -type f | sed 's/.*/"&"/' | xargs ls -E | awk '{ print $6," ",$7," ",$9 }' | sort | tail -1

Explanation

  • find . -type f finds and lists all files
  • sed 's/.*/"&"/' wraps the pathname in quotes to handle whitespaces
  • xargs ls -E sends the quoted path to ls, the -E option makes sure that a full timestamp (format year-month-day hour-minute-seconds-nanoseconds) is returned
  • awk '{ print $6," ",$7 }' extracts only date and time
  • awk '{ print $6," ",$7," ",$9 }' extracts date, time and filename
  • sort returns the files sorted by date
  • tail -1 returns only the last modified file

How to convert the background to transparent?

If you want a command-line solution, you can use the ImageMagick convert utility:

convert input.png -transparent red output.png

How to get file name from file path in android

Simple and easy way to get File name

File file = new File("/storage/sdcard0/DCIM/Camera/1414240995236.jpg"); 
String strFileName = file.getName();

After add this code and print strFileName you will get strFileName = 1414240995236.jpg

How do I display a decimal value to 2 decimal places?

Mike M.'s answer was perfect for me on .NET, but .NET Core doesn't have a decimal.Round method at the time of writing.

In .NET Core, I had to use:

decimal roundedValue = Math.Round(rawNumber, 2, MidpointRounding.AwayFromZero);

A hacky method, including conversion to string, is:

public string FormatTo2Dp(decimal myNumber)
{
    // Use schoolboy rounding, not bankers.
    myNumber = Math.Round(myNumber, 2, MidpointRounding.AwayFromZero);

    return string.Format("{0:0.00}", myNumber);
}

What is the purpose of using WHERE 1=1 in SQL statements?

Using 1=1 is actually not a very good idea as this can cause full table scans by itself.

See this--> T-SQL 1=1 Performance Hit

How to avoid using Select in Excel VBA

Working with the .Parent feature, this example shows how setting only one myRng reference enables dynamic access to the entire environment without any .Select, .Activate, .Activecell, .ActiveWorkbook, .ActiveSheet and so on. (There isn't any generic .Child feature.)

Sub ShowParents()
    Dim myRng As Range
    Set myRng = ActiveCell
    Debug.Print myRng.Address                    ' An address of the selected cell
    Debug.Print myRng.Parent.name                ' The name of sheet, where MyRng is in
    Debug.Print myRng.Parent.Parent.name         ' The name of workbook, where MyRng is in
    Debug.Print myRng.Parent.Parent.Parent.name  ' The name of application, where MyRng is in

    ' You may use this feature to set reference to these objects
    Dim mySh  As Worksheet
    Dim myWbk As Workbook
    Dim myApp As Application

    Set mySh = myRng.Parent
    Set myWbk = myRng.Parent.Parent
    Set myApp = myRng.Parent.Parent.Parent
    Debug.Print mySh.name, mySh.Cells(10, 1).Value
    Debug.Print myWbk.name, myWbk.Sheets.Count
    Debug.Print myApp.name, myApp.Workbooks.Count

    ' You may use dynamically addressing
    With myRng
        .Copy

        ' Pastes in D1 on sheet 2 in the same workbook, where the copied cell is
        .Parent.Parent.Sheets(2).Range("D1").PasteSpecial xlValues

        ' Or myWbk.Sheets(2).Range("D1").PasteSpecial xlValues

        ' We may dynamically call active application too
        .Parent.Parent.Parent.CutCopyMode = False

        ' Or myApp.CutCopyMode = False
    End With
End Sub

org.apache.catalina.core.StandardContext startInternal SEVERE: Error listenerStart

I had a similar problem. The catalina.out logged this log Message

Apr 17, 2013 5:14:46 PM org.apache.catalina.core.StandardContext start SEVERE: Error listenerStart

Check the localhost.log in the tomcat log directory (in the same directory as catalina.out), to see the exception which caused this error.

How to get HttpClient returning status code and response body?

BasicResponseHandler throws if the status is not 2xx. See its javadoc.

Here is how I would do it:

HttpResponse response = client.execute( get );
int code = response.getStatusLine().getStatusCode();
InputStream body = response.getEntity().getContent();
// Read the body stream

Or you can also write a ResponseHandler starting from BasicResponseHandler source that don't throw when the status is not 2xx.

Comparing strings by their alphabetical order

Take a look at the String.compareTo method.

s1.compareTo(s2)

From the javadocs:

The result is a negative integer if this String object lexicographically precedes the argument string. The result is a positive integer if this String object lexicographically follows the argument string. The result is zero if the strings are equal; compareTo returns 0 exactly when the equals(Object) method would return true.

How to pad a string with leading zeros in Python 3

I suggest this ugly method but it works:

length = 1
lenghtafterpadding = 3
newlength = '0' * (lenghtafterpadding - len(str(length))) + str(length)

I came here to find a lighter solution than this one!

Populate one dropdown based on selection in another

Could you please have a look at: http://jsfiddle.net/4Zw3M/1/.

Basically, the data is stored in an Array and the options are added accordingly. I think the code says more than a thousand words.

var data = [ // The data
    ['ten', [
        'eleven','twelve'
    ]],
    ['twenty', [
        'twentyone', 'twentytwo'
    ]]
];

$a = $('#a'); // The dropdowns
$b = $('#b');

for(var i = 0; i < data.length; i++) {
    var first = data[i][0];
    $a.append($("<option>"). // Add options
       attr("value",first).
       data("sel", i).
       text(first));
}

$a.change(function() {
    var index = $(this).children('option:selected').data('sel');
    var second = data[index][1]; // The second-choice data

    $b.html(''); // Clear existing options in second dropdown

    for(var j = 0; j < second.length; j++) {
        $b.append($("<option>"). // Add options
           attr("value",second[j]).
           data("sel", j).
           text(second[j]));
    }
}).change(); // Trigger once to add options at load of first choice

Public class is inaccessible due to its protection level

This error is a result of the protection level of ClassB's constructor, not ClassB itself. Since the name of the constructor is the same as the name of the class* , the error may be interpreted incorrectly. Since you did not specify the protection level of your constructor, it is assumed to be internal by default. Declaring the constructor public will fix this problem:

public ClassB() { } 

* One could also say that constructors have no name, only a type; this does not change the essence of the problem.

Error resolving template "index", template might not exist or might not be accessible by any of the configured Template Resolvers

I am new to spring spent an hour trying to figure this out.

go to --- > application.properties

add these :

spring.thymeleaf.prefix=classpath:/templates/
spring.thymeleaf.suffix=.html

How to lowercase a pandas dataframe string column if it has missing values?

Use apply function,

Xlower = df['x'].apply(lambda x: x.upper()).head(10) 

T-SQL loop over query results

DECLARE @id INT
DECLARE @name NVARCHAR(100)
DECLARE @getid CURSOR

SET @getid = CURSOR FOR
SELECT table.id,
       table.name
FROM   table

WHILE 1=1
BEGIN

    FETCH NEXT
    FROM @getid INTO @id, @name
    IF @@FETCH_STATUS < 0 BREAK

    EXEC stored_proc @varName=@id, @otherVarName='test', @varForName=@name

END

CLOSE @getid
DEALLOCATE @getid

Running Node.js in apache?

Although there are a lot of good tips here I'd like to answer the question you asked:

So in other words can they work hand in hand just like Apache/Perl or Apache/PHP etc..

YES, you can run Node.js on Apache along side Perl and PHP IF you run it as a CGI module. As of yet, I am unable to find a mod-node for Apache but check out: CGI-Node for Apache here http://www.cgi-node.org/ .

The interesting part about cgi-node is that it uses JavaScript exactly like you would use PHP to generate dynamic content, service up static pages, access SQL database etc. You can even share core JavaScript libraries between the server and the client/browser.

I think the shift to a single language between client and server is happening and JavaScript seems to be a good candidate.

A quick example from cgi-node.org site:

<? include('myJavaScriptFile.js'); ?>
<html>
   <body>
      <? var helloWorld = 'Hello World!'; ?>
      <b><?= helloWorld ?><br/>
      <? for( var index = 0; index < 10; index++) write(index + ' '); ?>
   </body>
</html>

This outputs:

Hello World!
0 1 2 3 4 5 6 7 8 9

You also have full access to the HTTP request. That includes forms, uploaded files, headers etc.

I am currently running Node.js through the cgi-node module on Godaddy.

CGI-Node.org site has all the documentation to get started.

I know I'm raving about this but it is finally a relief to use something other than PHP. Also, to be able to code JavaScript on both client and server.

Hope this helps.

Why are Python's 'private' methods not actually private?

With Python 3.4 this is the behaviour:

>>> class Foo:
        def __init__(self):
                pass
        def __privateMethod(self):
                return 3
        def invoke(self):
                return self.__privateMethod()


>>> help(Foo)
Help on class Foo in module __main__:

class Foo(builtins.object)
 |  Methods defined here:
 |
 |  __init__(self)
 |
 |  invoke(self)
 |
 |  ----------------------------------------------------------------------
 |  Data descriptors defined here:
 |
 |  __dict__
 |      dictionary for instance variables (if defined)
 |
 |  __weakref__
 |      list of weak references to the object (if defined)

 >>> f = Foo()
 >>> f.invoke()
 3
 >>> f.__privateMethod()
 Traceback (most recent call last):
   File "<pyshell#47>", line 1, in <module>
     f.__privateMethod()
 AttributeError: 'Foo' object has no attribute '__privateMethod'

https://docs.python.org/3/tutorial/classes.html#tut-private

Note that the mangling rules are designed mostly to avoid accidents; it still is possible to access or modify a variable that is considered private. This can even be useful in special circumstances, such as in the debugger.

Even if the question is old I hope my snippet could be helpful.

What is the difference between Promises and Observables?

Both Promises and Observables help us dealing with asynchronous operations. They can call certain callbacks when these asynchronous operations are done.

Angular uses Observables which is from RxJS instead of promises for dealing with HTTP

Below are some important differences in promises & Observables.

difference between Promises and Observables

angular 2 sort and filter

You must create your own Pipe for array sorting, here is one example how can you do that.

<li *ngFor="#item of array | arraySort:'-date'">{{item.name}} {{item.date | date:'medium' }}</li>

https://plnkr.co/edit/DU6pxr?p=preview

MySQL: NOT LIKE

I don't know why

cfg_name_unique NOT LIKE '%categories%' 

still returns those two values, but maybe exclude them explicit:

SELECT *
    FROM developer_configurations_cms

    WHERE developer_configurations_cms.cat_id = '1'
    AND developer_configurations_cms.cfg_variables LIKE '%parent_id=2%'
    AND developer_configurations_cms.cfg_name_unique NOT LIKE '%categories%'
    AND developer_configurations_cms.cfg_name_unique NOT IN ('categories_posts', 'categories_news')

How to localise a string inside the iOS info.plist file?

I would highly recommend reading Apple's guides, and viewing the WWDC resources listed here: Internationalization and Localization Topics

To specifically answer your question, when you add a new language to your projectenter image description here, you get an opportunity to choose what InfoPlist files to include (if you have multiple targets, you'll have multiple Info plist files). All you need to do to get the following screen is hit the + under Localizations and choose a new language to add support for. enter image description here

Once you've added, it will create the necessary string files in the appropriate lproj directories for the given language.

--EDIT--

Just to be clear, iOS will swap out the string for your Plist file based upon the user's currently selected language using the plist entry's key as the key in the localized strings file.

How do I call an Angular.js filter with multiple arguments?

i mentioned in the below where i have mentioned the custom filter also , how to call these filter which is having two parameters

countryApp.filter('reverse', function() {
    return function(input, uppercase) {
        var out = '';
        for (var i = 0; i < input.length; i++) {
            out = input.charAt(i) + out;
        }
        if (uppercase) {
            out = out.toUpperCase();
        }
        return out;
    }
});

and from the html using the template we can call that filter like below

<h1>{{inputString| reverse:true }}</h1>

here if you see , the first parameter is inputString and second parameter is true which is combined with "reverse' using the : symbol

Groovy: How to check if a string contains any element of an array?

def valid = pointAddress.findAll { a ->
    validPointTypes.any { a.contains(it) }
}

Should do it

Android - How To Override the "Back" button so it doesn't Finish() my Activity?

Looks like im very late but for those of you who need to switch to new screen and clear back button stack here is a very simple solution.

startActivity(new Intent(this,your-new-screen.class));
finishAffinity();

The finishAffinity(); method clears back button stack.

Jquery in React is not defined

I just want to receive ajax request, but the problem is that jQuery is not defined in React.

Then don't use it. Use Fetch and have a look at Fetch polyfill in React not completely working in IE 11 to see example of alternative ways to get it running

Something like this

const that = this; 
fetch('http://jsonplaceholder.typicode.com/posts') 
  .then(function(response) { return response.json(); }) 
  .then(function(myJson) { 
     that.setState({data: myJson}); // for example
  });

Can I use Objective-C blocks as properties?

Here's an example of how you would accomplish such a task:

#import <Foundation/Foundation.h>
typedef int (^IntBlock)();

@interface myobj : NSObject
{
    IntBlock compare;
}

@property(readwrite, copy) IntBlock compare;

@end

@implementation myobj

@synthesize compare;

- (void)dealloc 
{
   // need to release the block since the property was declared copy. (for heap
   // allocated blocks this prevents a potential leak, for compiler-optimized 
   // stack blocks it is a no-op)
   // Note that for ARC, this is unnecessary, as with all properties, the memory management is handled for you.
   [compare release];
   [super dealloc];
}
@end

int main () {
    @autoreleasepool {
        myobj *ob = [[myobj alloc] init];
        ob.compare = ^
        {
            return rand();
        };
        NSLog(@"%i", ob.compare());
        // if not ARC
        [ob release];
    }

    return 0;
}

Now, the only thing that would need to change if you needed to change the type of compare would be the typedef int (^IntBlock)(). If you need to pass two objects to it, change it to this: typedef int (^IntBlock)(id, id), and change your block to:

^ (id obj1, id obj2)
{
    return rand();
};

I hope this helps.

EDIT March 12, 2012:

For ARC, there are no specific changes required, as ARC will manage the blocks for you as long as they are defined as copy. You do not need to set the property to nil in your destructor, either.

For more reading, please check out this document: http://clang.llvm.org/docs/AutomaticReferenceCounting.html

get parent's view from a layout

The getParent method returns a ViewParent, not a View. You need to cast the first call to getParent() also:

RelativeLayout r = (RelativeLayout) ((ViewGroup) this.getParent()).getParent();

As stated in the comments by the OP, this is causing a NPE. To debug, split this up into multiple parts:

ViewParent parent = this.getParent();
RelativeLayout r;
if (parent == null) {
    Log.d("TEST", "this.getParent() is null");
}
else {
    if (parent instanceof ViewGroup) {
        ViewParent grandparent = ((ViewGroup) parent).getParent();
        if (grandparent == null) {
            Log.d("TEST", "((ViewGroup) this.getParent()).getParent() is null");
        }
        else {
            if (parent instanceof RelativeLayout) {
                r = (RelativeLayout) grandparent;
            }
            else {
                Log.d("TEST", "((ViewGroup) this.getParent()).getParent() is not a RelativeLayout");
            }
        }
    }
    else {
        Log.d("TEST", "this.getParent() is not a ViewGroup");
    }
}

//now r is set to the desired RelativeLayout.

How to call another components function in angular2

First, what you need to understand the relationships between components. Then you can choose the right method of communication. I will try to explain all the methods that I know and use in my practice for communication between components.

What kinds of relationships between components can there be?

1. Parent > Child

enter image description here

Sharing Data via Input

This is probably the most common method of sharing data. It works by using the @Input() decorator to allow data to be passed via the template.

parent.component.ts

import { Component } from '@angular/core';

@Component({
  selector: 'parent-component',
  template: `
    <child-component [childProperty]="parentProperty"></child-component>
  `,
  styleUrls: ['./parent.component.css']
})
export class ParentComponent{
  parentProperty = "I come from parent"
  constructor() { }
}

child.component.ts

import { Component, Input } from '@angular/core';

@Component({
  selector: 'child-component',
  template: `
      Hi {{ childProperty }}
  `,
  styleUrls: ['./child.component.css']
})
export class ChildComponent {

  @Input() childProperty: string;

  constructor() { }

}

This is a very simple method. It is easy to use. We can also catch changes to the data in the child component using ngOnChanges.

But do not forget that if we use an object as data and change the parameters of this object, the reference to it will not change. Therefore, if we want to receive a modified object in a child component, it must be immutable.

2. Child > Parent

enter image description here

Sharing Data via ViewChild

ViewChild allows one component to be injected into another, giving the parent access to its attributes and functions. One caveat, however, is that child won’t be available until after the view has been initialized. This means we need to implement the AfterViewInit lifecycle hook to receive the data from the child.

parent.component.ts

import { Component, ViewChild, AfterViewInit } from '@angular/core';
import { ChildComponent } from "../child/child.component";

@Component({
  selector: 'parent-component',
  template: `
    Message: {{ message }}
    <child-compnent></child-compnent>
  `,
  styleUrls: ['./parent.component.css']
})
export class ParentComponent implements AfterViewInit {

  @ViewChild(ChildComponent) child;

  constructor() { }

  message:string;

  ngAfterViewInit() {
    this.message = this.child.message
  }
}

child.component.ts

import { Component} from '@angular/core';

@Component({
  selector: 'child-component',
  template: `
  `,
  styleUrls: ['./child.component.css']
})
export class ChildComponent {

  message = 'Hello!';

  constructor() { }

}

Sharing Data via Output() and EventEmitter

Another way to share data is to emit data from the child, which can be listed by the parent. This approach is ideal when you want to share data changes that occur on things like button clicks, form entries, and other user events.

parent.component.ts

import { Component } from '@angular/core';

@Component({
  selector: 'parent-component',
  template: `
    Message: {{message}}
    <child-component (messageEvent)="receiveMessage($event)"></child-component>
  `,
  styleUrls: ['./parent.component.css']
})
export class ParentComponent {

  constructor() { }

  message:string;

  receiveMessage($event) {
    this.message = $event
  }
}

child.component.ts

import { Component, Output, EventEmitter } from '@angular/core';

@Component({
  selector: 'child-component',
  template: `
      <button (click)="sendMessage()">Send Message</button>
  `,
  styleUrls: ['./child.component.css']
})
export class ChildComponent {

  message: string = "Hello!"

  @Output() messageEvent = new EventEmitter<string>();

  constructor() { }

  sendMessage() {
    this.messageEvent.emit(this.message)
  }
}

3. Siblings

enter image description here

Child > Parent > Child

I try to explain other ways to communicate between siblings below. But you could already understand one of the ways of understanding the above methods.

parent.component.ts

import { Component } from '@angular/core';

@Component({
  selector: 'parent-component',
  template: `
    Message: {{message}}
    <child-one-component (messageEvent)="receiveMessage($event)"></child1-component>
    <child-two-component [childMessage]="message"></child2-component>
  `,
  styleUrls: ['./parent.component.css']
})
export class ParentComponent {

  constructor() { }

  message: string;

  receiveMessage($event) {
    this.message = $event
  }
}

child-one.component.ts

import { Component, Output, EventEmitter } from '@angular/core';

@Component({
  selector: 'child-one-component',
  template: `
      <button (click)="sendMessage()">Send Message</button>
  `,
  styleUrls: ['./child-one.component.css']
})
export class ChildOneComponent {

  message: string = "Hello!"

  @Output() messageEvent = new EventEmitter<string>();

  constructor() { }

  sendMessage() {
    this.messageEvent.emit(this.message)
  }
}

child-two.component.ts

import { Component, Input } from '@angular/core';

@Component({
  selector: 'child-two-component',
  template: `
       {{ message }}
  `,
  styleUrls: ['./child-two.component.css']
})
export class ChildTwoComponent {

  @Input() childMessage: string;

  constructor() { }

}

4. Unrelated Components

enter image description here

All the methods that I have described below can be used for all the above options for the relationship between the components. But each has its own advantages and disadvantages.

Sharing Data with a Service

When passing data between components that lack a direct connection, such as siblings, grandchildren, etc, you should be using a shared service. When you have data that should always be in sync, I find the RxJS BehaviorSubject very useful in this situation.

data.service.ts

import { Injectable } from '@angular/core';
import { BehaviorSubject } from 'rxjs';

@Injectable()
export class DataService {

  private messageSource = new BehaviorSubject('default message');
  currentMessage = this.messageSource.asObservable();

  constructor() { }

  changeMessage(message: string) {
    this.messageSource.next(message)
  }

}

first.component.ts

import { Component, OnInit } from '@angular/core';
import { DataService } from "../data.service";

@Component({
  selector: 'first-componennt',
  template: `
    {{message}}
  `,
  styleUrls: ['./first.component.css']
})
export class FirstComponent implements OnInit {

  message:string;

  constructor(private data: DataService) {
      // The approach in Angular 6 is to declare in constructor
      this.data.currentMessage.subscribe(message => this.message = message);
  }

  ngOnInit() {
    this.data.currentMessage.subscribe(message => this.message = message)
  }

}

second.component.ts

import { Component, OnInit } from '@angular/core';
import { DataService } from "../data.service";

@Component({
  selector: 'second-component',
  template: `
    {{message}}
    <button (click)="newMessage()">New Message</button>
  `,
  styleUrls: ['./second.component.css']
})
export class SecondComponent implements OnInit {

  message:string;

  constructor(private data: DataService) { }

  ngOnInit() {
    this.data.currentMessage.subscribe(message => this.message = message)
  }

  newMessage() {
    this.data.changeMessage("Hello from Second Component")
  }

}

Sharing Data with a Route

Sometimes you need not only pass simple data between component but save some state of the page. For example, we want to save some filter in the online market and then copy this link and send to a friend. And we expect it to open the page in the same state as us. The first, and probably the quickest, way to do this would be to use query parameters.

Query parameters look more along the lines of /people?id= where id can equal anything and you can have as many parameters as you want. The query parameters would be separated by the ampersand character.

When working with query parameters, you don’t need to define them in your routes file, and they can be named parameters. For example, take the following code:

page1.component.ts

import {Component} from "@angular/core";
import {Router, NavigationExtras} from "@angular/router";

@Component({
    selector: "page1",
  template: `
    <button (click)="onTap()">Navigate to page2</button>
  `,
})
export class Page1Component {

    public constructor(private router: Router) { }

    public onTap() {
        let navigationExtras: NavigationExtras = {
            queryParams: {
                "firstname": "Nic",
                "lastname": "Raboy"
            }
        };
        this.router.navigate(["page2"], navigationExtras);
    }

}

In the receiving page, you would receive these query parameters like the following:

page2.component.ts

import {Component} from "@angular/core";
import {ActivatedRoute} from "@angular/router";

@Component({
    selector: "page2",
    template: `
         <span>{{firstname}}</span>
         <span>{{lastname}}</span>
      `,
})
export class Page2Component {

    firstname: string;
    lastname: string;

    public constructor(private route: ActivatedRoute) {
        this.route.queryParams.subscribe(params => {
            this.firstname = params["firstname"];
            this.lastname = params["lastname"];
        });
    }

}

NgRx

The last way, which is more complicated but more powerful, is to use NgRx. This library is not for data sharing; it is a powerful state management library. I can't in a short example explain how to use it, but you can go to the official site and read the documentation about it.

To me, NgRx Store solves multiple issues. For example, when you have to deal with observables and when responsibility for some observable data is shared between different components, the store actions and reducer ensure that data modifications will always be performed "the right way".

It also provides a reliable solution for HTTP requests caching. You will be able to store the requests and their responses so that you can verify that the request you're making does not have a stored response yet.

You can read about NgRx and understand whether you need it in your app or not:

Finally, I want to say that before choosing some of the methods for sharing data you need to understand how this data will be used in the future. I mean maybe just now you can use just an @Input decorator for sharing a username and surname. Then you will add a new component or new module (for example, an admin panel) which needs more information about the user. This means that may be a better way to use a service for user data or some other way to share data. You need to think about it more before you start implementing data sharing.

rbind error: "names do not match previous names"

The names of the first dataframe do not match the names of the second one. Just as the error message says.

> identical(names(xd.small[[1]]), names(xd.small[[2]]) )
[1] FALSE

If you do not care about the names of the 3rd or 4th columns of the second df, you can coerce them to be the same:

> names(xd.small[[1]]) <- names(xd.small[[2]]) 
> identical(names(xd.small[[1]]), names(xd.small[[2]]) )
[1] TRUE

Then things should proceed happily.

How to get the timezone offset in GMT(Like GMT+7:00) from android device?

Yet another solution to get timezone offset:

TimeZone tz = TimeZone.getDefault();
String current_Time_Zone = getGmtOffsetString(tz.getRawOffset());

public static String getGmtOffsetString(int offsetMillis) {
    int offsetMinutes = offsetMillis / 60000;
    char sign = '+';
    if (offsetMinutes < 0) {
        sign = '-';
        offsetMinutes = -offsetMinutes;
    }
    return String.format("GMT%c%02d:%02d", sign, offsetMinutes/60, offsetMinutes % 60);
}

Superscript in CSS only?

The CSS property font-variant-position is under consideration and may eventually be the answer to this question. As of early 2017, only Firefox supports it, though.

.super {
    font-variant-position: super;
}

See MDN.

How to restore to a different database in sql server?

Here is how to restore a backup as an additional db with a unique db name.

For SQL 2005 this works very quickly. I am sure newer versions will work the same.

First, you don't have to take your original db offline. But for safety sake, I like to. In my example, I am going to mount a clone of my "billing" database and it will be named "billingclone".

1) Make a good backup of the billing database

2) For safety, I took the original offline as follows:

3) Open a new Query window

**IMPORTANT! Keep this query window open until you are all done! You need to restore the db from this window!

Now enter the following code:

-- 1) free up all USER databases
USE master;
GO
-- 2) kick all other users out:
ALTER DATABASE billing SET SINGLE_USER WITH ROLLBACK IMMEDIATE;
GO
-- 3) prevent sessions from re-establishing connection:
ALTER DATABASE billing SET OFFLINE;

3) Next, in Management Studio, rt click Databases in Object Explorer, choose "Restore Database"

4) enter new name in "To Database" field. I.E. billingclone

5) In Source for Restore, click "From Device" and click the ... navigate button

6) Click Add and navigate to your backup

7) Put a checkmark next to Restore (Select the backup sets to restore)

8) next select the OPTIONS page in upper LH corner

9) Now edit the database file names in RESTORE AS. Do this for both the db and the log. I.E. billingclone.mdf and billingclone_log.ldf

10) now hit OK and wait for the task to complete.

11) Hit refresh in your Object Explorer and you will see your new db

12) Now you can put your billing db back online. Use the same query window you used to take billing offline. Use this command:

-- 1) free up all USER databases
USE master; GO
-- 2) restore access to all users:
ALTER DATABASE billing SET MULTI_USER WITH ROLLBACK IMMEDIATE;GO
-- 3) put the db back online:
ALTER DATABASE billing SET ONLINE;

done!

How to print a dictionary line by line in Python?

Check the following one-liner:

print('\n'.join("%s\n%s" % (key1,('\n'.join("%s : %r" % (key2,val2) for (key2,val2) in val1.items()))) for (key1,val1) in cars.items()))

Output:

A
speed : 70
color : 2
B
speed : 60
color : 3

Right query to get the current number of connections in a PostgreSQL DB

Those two requires aren't equivalent. The equivalent version of the first one would be:

SELECT sum(numbackends) FROM pg_stat_database;

In that case, I would expect that version to be slightly faster than the second one, simply because it has fewer rows to count. But you are not likely going to be able to measure a difference.

Both queries are based on exactly the same data, so they will be equally accurate.

What is the syntax for Typescript arrow functions with generics?

This works for me

const Generic = <T> (value: T) => {
    return value;
} 

How to convert std::string to LPCWSTR in C++ (Unicode)

The solution is actually a lot easier than any of the other suggestions:

std::wstring stemp = std::wstring(s.begin(), s.end());
LPCWSTR sw = stemp.c_str();

Best of all, it's platform independent.

How do I Alter Table Column datatype on more than 1 column?

ALTER TABLE can do multiple table alterations in one statement, but MODIFY COLUMN can only work on one column at a time, so you need to specify MODIFY COLUMN for each column you want to change:

ALTER TABLE webstore.Store
  MODIFY COLUMN ShortName VARCHAR(100),
  MODIFY COLUMN UrlShort VARCHAR(100);

Also, note this warning from the manual:

When you use CHANGE or MODIFY, column_definition must include the data type and all attributes that should apply to the new column, other than index attributes such as PRIMARY KEY or UNIQUE. Attributes present in the original definition but not specified for the new definition are not carried forward.

How to read from a text file using VBScript?

Use first the method OpenTextFile, and then...

either read the file at once with the method ReadAll:

Set file = fso.OpenTextFile("C:\test.txt", 1)
content = file.ReadAll

or line by line with the method ReadLine:

Set dict = CreateObject("Scripting.Dictionary")
Set file = fso.OpenTextFile ("c:\test.txt", 1)
row = 0
Do Until file.AtEndOfStream
  line = file.Readline
  dict.Add row, line
  row = row + 1
Loop

file.Close

'Loop over it
For Each line in dict.Items
  WScript.Echo line
Next

Requested bean is currently in creation: Is there an unresolvable circular reference?

Spring uses an special logic for resolving this kind of circular dependencies with singleton beans. But this won't apply to other scopes. There is no elegant way of breaking this circular dependency, but a clumsy option could be this one:

@Component("bean1")
@Scope("view")
public class Bean1 {

    @Autowired
    private Bean2 bean2;

    @PostConstruct
    public void init() {
        bean2.setBean1(this);
    }
}

@Component("bean2")
@Scope("view")
public class Bean2 {

    private Bean1 bean1;

    public void setBean1(Bean1 bean1) {
        this.bean1 = bean1;
    }
}

Anyway, circular dependencies are usually a symptom of bad design. You would think again if there is some better way of defining your class dependencies.

how to customize `show processlist` in mysql?

The command

show full processlist

can be replaced by:

SELECT * FROM information_schema.processlist

but if you go with the latter version you can add WHERE clause to it:

SELECT * FROM information_schema.processlist WHERE `INFO` LIKE 'SELECT %';

For more information visit this

Webdriver and proxy server for firefox

Firefox Proxy: JAVA

String PROXY = "localhost:8080";

org.openqa.selenium.Proxy proxy = new org.openqa.selenium.Proxy();

proxy.setHttpProxy(PROXY)setFtpProxy(PROXY).setSslProxy(PROXY);

DesiredCapabilities cap = new DesiredCapabilities();

cap.setCapability(CapabilityType.PROXY, proxy); 

WebDriver driver = new FirefoxDriver(cap);

OSError: [Errno 2] No such file or directory while using python subprocess in Django

Use shell=True if you're passing a string to subprocess.call.

From docs:

If passing a single string, either shell must be True or else the string must simply name the program to be executed without specifying any arguments.

subprocess.call(crop, shell=True)

or:

import shlex
subprocess.call(shlex.split(crop))

jQuery $("#radioButton").change(...) not firing during de-selection

My problem was similar and this worked for me:

$('body').on('change', '.radioClassNameHere', function() { ...

ERROR 2003 (HY000): Can't connect to MySQL server on '127.0.0.1' (111)

This happens when you forget to start the database before connecting to it:

mysql.server start

then

mysql -u root -p -h 127.0.0.1

Converting a string to an integer on Android

You can also do it one line:

int hello = Integer.parseInt(((Button)findViewById(R.id.button1)).getText().toString().replaceAll("[\\D]", ""));

Reading from order of execution

  1. grab the view using findViewById(R.id.button1)
  2. use ((Button)______) to cast the View as a Button
  3. Call .GetText() to get the text entry from Button
  4. Call .toString() to convert the Character Varying to a String
  5. Call .ReplaceAll() with "[\\D]" to replace all Non Digit Characters with "" (nothing)
  6. Call Integer.parseInt() grab and return an integer out of the Digit-only string.

Best way to do a split pane in HTML

Simplest HTML + CSS accordion, with just CSS resize.

_x000D_
_x000D_
div {
  resize: vertical;
  overflow: auto;
  border: 1px solid
}
.menu {
  display: grid
  /* Try height: 100% or height: 100vh */
}
_x000D_
<div class="menu">
  <div>
    Hello, World!
  </div>
  <div>
    Hello, World!
  </div>
  <div>
    Hello, World!
  </div>
</div>
_x000D_
_x000D_
_x000D_


Simplest HTML + CSS vertical resizable panes:

_x000D_
_x000D_
div {
  resize: horizontal;
  overflow: auto;
  border: 1px solid;
  display: inline-flex;
  height: 90vh
}
_x000D_
<div>
  Hello, World!
</div>
<div>
  Hello, World!
</div>
_x000D_
_x000D_
_x000D_


The plain HTML, details element!.

_x000D_
_x000D_
<details>
  <summary>Morning</summary>
  <p>Hello, World!</p>
</details>
<details>
  <summary>Evening</summary>
  <p>How sweat?</p>
</details>
_x000D_
_x000D_
_x000D_


Simplest HTML + CSS topbar foldable menu

_x000D_
_x000D_
div{
 display: flex
}
summary,p{
 margin: 0px 0 -1px 0px;
 padding: 0 0 0 0.5rem;
 border: 1px black solid
}
summary {
  padding: 0 1rem 0 0.5rem
}
_x000D_
<div>
  <details>
    <summary>FILE</summary>
    <p>Save</p>
    <p>Save as</p>
  </details>
  <details>
    <summary>EDIT</summary>
    <p>Pump</p>
    <p>Transfer</p>
    <p>Review</p>
    <p>Compile</p>
  </details>
  <details>
    <summary>PREFERENCES</summary>
    <p>How sweat?</p>
    <p>Powered by HTML</p>
  </details>
</div>
_x000D_
_x000D_
_x000D_


Fixed bottom menu bar, unfolding upward.

_x000D_
_x000D_
div{
 display: flex;
 position: fixed;
 bottom: 0;
 transform: rotate(180deg)
}
summary,p{
 margin: 0px 0 -1px 0px;
 padding: 0 0 0 0.5rem;
 border: 1px black solid;
 transform: rotate(180deg)
}
summary {
  padding: 0 1rem 0 0.5rem;
}
_x000D_
<div>
  <details>
    <summary>FILE</summary>
    <p>Save</p>
    <p>Save as</p>
  </details>
  <details>
    <summary>EDIT</summary>
    <p>Pump</p>
    <p>Transfer</p>
    <p>Review</p>
    <p>Compile</p>
  </details>
  <details>
    <summary>PREF</summary>
    <p>How?</p>
    <p>Power</p>
  </details>
</div>
_x000D_
_x000D_
_x000D_


Simplest resizable pane, using JavaScript.

_x000D_
_x000D_
let ismdwn = 0
rpanrResize.addEventListener('mousedown', mD)

function mD(event) {
  ismdwn = 1
  document.body.addEventListener('mousemove', mV)
  document.body.addEventListener('mouseup', end)
}

function mV(event) {
  if (ismdwn === 1) {
    pan1.style.flexBasis = event.clientX + "px"
  } else {
    end()
  }
}
const end = (e) => {
  ismdwn = 0
  document.body.removeEventListener('mouseup', end)
  rpanrResize.removeEventListener('mousemove', mV)
}
_x000D_
div {
  display: flex;
  border: 1px black solid;
  width: 100%;
  height: 200px;
}

#pan1 {
  flex-grow: 1;
  flex-shrink: 0;
  flex-basis: 50%; // initial status
}

#pan2 {
  flex-grow: 0;
  flex-shrink: 1;
  overflow-x: auto;
}

#rpanrResize {
  flex-grow: 0;
  flex-shrink: 0;
  background: #1b1b51;
  width: 0.2rem;
  cursor: col-resize;
  margin: 0 0 0 auto;
}
_x000D_
<div>
  <div id="pan1">MENU</div>
  <div id="rpanrResize">&nbsp;</div>
  <div id="pan2">BODY</div>
</div>
_x000D_
_x000D_
_x000D_

Assign one struct to another in C

Yes, assignment is supported for structs. However, there are problems:

struct S {
   char * p;
};

struct S s1, s2;
s1.p = malloc(100);
s2 = s1;

Now the pointers of both structs point to the same block of memory - the compiler does not copy the pointed to data. It is now difficult to know which struct instance owns the data. This is why C++ invented the concept of user-definable assignment operators - you can write specific code to handle this case.

How to select all textareas and textboxes using jQuery?

Simply use $(":input")

Example disabling all inputs (textarea, input text, etc):

_x000D_
_x000D_
$(":input").prop("disabled", true);
_x000D_
<form>_x000D_
  <textarea>Tetarea</textarea>_x000D_
  <input type="text" value="Text">_x000D_
  <label><input type="checkbox"> Checkbox</label>_x000D_
</form>_x000D_
_x000D_
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
_x000D_
_x000D_
_x000D_

How do I get the type of a variable?

If you need to make a comparison between a class and a known type, for example:

class Example{};
...
Example eg = Example();

You can use this comparison line:

bool isType = string( typeid(eg).name() ).find("Example") != string::npos;

which checks the typeid name contains the string type (the typeid name has other mangled data, so its best to do a s1.find(s2) instead of ==).

Do the parentheses after the type name make a difference with new?

Assuming that Test is a class with a defined constructor, there's no difference. The latter form makes it a little clearer that Test's constructor is running, but that's about it.

How to use Bootstrap 4 in ASP.NET Core

Use nmp configuration file (add it to your web project) then add the needed packages in the same way we did using bower.json and save. Visual studio will download and install it. You'll find the package the under the nmp node of your project.

How do I wait for a promise to finish before returning the variable of a function?

What do I need to do to make this function wait for the result of the promise?

Use async/await (NOT Part of ECMA6, but available for Chrome, Edge, Firefox and Safari since end of 2017, see canIuse)
MDN

    async function waitForPromise() {
        // let result = await any Promise, like:
        let result = await Promise.resolve('this is a sample promise');
    }

Added due to comment: An async function always returns a Promise, and in TypeScript it would look like:

    async function waitForPromise(): Promise<string> {
        // let result = await any Promise, like:
        let result = await Promise.resolve('this is a sample promise');
    }

Could not find folder 'tools' inside SDK

My solution was to remove the Eclipse ADT plugin via menu "Help > About Eclipse SDK > Installation Details". Eclipse will restart.

Next go to Menu "Help > Install New Software", then add the ADT plugin url "https://dl-ssl.google.com/android/eclipse" (or select the existing link from the dropdown).

This will re-install the latest ADT, including the DDMS files.

get current date and time in groovy?

Date has the time part, so we only need to extract it from Date

I personally prefer the default format parameter of the Date when date and time needs to be separated instead of using the extra SimpleDateFormat

Date date = new Date()
String datePart = date.format("dd/MM/yyyy")
String timePart = date.format("HH:mm:ss")

println "datePart : " + datePart + "\ttimePart : " + timePart

Replace all occurrences of a String using StringBuilder?

How about create a method and let String.replaceAll do it for you:

public static void replaceAll(StringBuilder sb, String regex, String replacement)
{
    String aux = sb.toString();
    aux = aux.replaceAll(regex, replacement);
    sb.setLength(0);
    sb.append(aux);     
}

failed to open stream: HTTP wrapper does not support writeable connections

it is because of using web address, You can not use http to write data. don't use : http:// or https:// in your location for upload files or save data or somting like that. instead of of using $_SERVER["HTTP_REFERER"] use $_SERVER["DOCUMENT_ROOT"]. for example :

wrong :

move_uploaded_file($_FILES["File"]["tmp_name"],$_SERVER["HTTP_REFERER"].'/uploads/images/1.jpg')

correct:

move_uploaded_file($_FILES["File"]["tmp_name"],$_SERVER["DOCUMENT_ROOT"].'/uploads/images/1.jpg')

show loading icon until the page is load?

add class="loading" in the body tag then use below script with follwing css code

body {
            -webkit-transition: background-color 1s;
            transition: background-color 1s;
        }
        html, body { min-height: 100%; }
        body.loading {
            background: #333 url('http://code.jquery.com/mobile/1.3.1/images/ajax-loader.gif') no-repeat 50% 50%;
            -webkit-transition: background-color 0;
            transition: background-color 0;
            opacity: 0;
            -webkit-transition: opacity 0;
            transition: opacity 0;
        }

Use this code

var body = document.getElementsByTagName('body')[0];
var removeLoading = function() {
    setTimeout(function() {
        body.className = body.className.replace(/loading/, '');
    }, 3000);
};
removeLoading();

Demo: https://jsfiddle.net/0qpuaeph/

How to add Class in <li> using wp_nav_menu() in Wordpress?

You can't add a class directly to the LIs very easily, but is there any reason not to target them in a slightly different but equally specific way (by their parent ul)?

You can set the class or ID of the menu with the menu_class and menu_id parameters (affixed to the UL parent of the LIs) and then target the li's via CSS that way, like so:

<?php wp_nav_menu('menu_id=mymenu'); ?>

And for CSS:

ul#mymenu li {
    /* your styles here */
}

Edit: At the time of writing in 2013 this was the easiest way to add it, but updates since then have added the feature to add CSS classes directly in the admin navigation editor. See more recent answers for details.

Does a VPN Hide my Location on Android?

Your question can be conveniently divided into several parts:

Does a VPN hide location? Yes, he is capable of this. This is not about GPS determining your location. If you try to change the region via VPN in an application that requires GPS access, nothing will work. However, sites define your region differently. They get an IP address and see what country or region it belongs to. If you can change your IP address, you can change your region. This is exactly what VPNs can do.

How to hide location on Android? There is nothing difficult in figuring out how to set up a VPN on Android, but a couple of nuances still need to be highlighted. Let's start with the fact that not all Android VPNs are created equal. For example, VeePN outperforms many other services in terms of efficiency in circumventing restrictions. It has 2500+ VPN servers and a powerful IP and DNS leak protection system.

You can easily change the location of your Android device by using a VPN. Follow these steps for any device model (Samsung, Sony, Huawei, etc.):

  1. Download and install a trusted VPN.

  2. Install the VPN on your Android device.

  3. Open the application and connect to a server in a different country.

  4. Your Android location will now be successfully changed!

Is it legal? Yes, changing your location on Android is legal. Likewise, you can change VPN settings in Microsoft Edge on your PC, and all this is within the law. VPN allows you to change your IP address, safeguarding your privacy and protecting your actual location from being exposed. However, VPN laws may vary from country to country. There are restrictions in some regions.

Brief summary: Yes, you can change your region on Android and a VPN is a necessary assistant for this. It's simple, safe and legal. Today, VPN is the best way to change the region and unblock sites with regional restrictions.

Segmentation fault on large array sizes

You're probably just getting a stack overflow here. The array is too big to fit in your program's stack address space.

If you allocate the array on the heap you should be fine, assuming your machine has enough memory.

int* array = new int[1000000];

But remember that this will require you to delete[] the array. A better solution would be to use std::vector<int> and resize it to 1000000 elements.

Running multiple AsyncTasks at the same time -- not possible?

The android developers example of loading bitmaps efficiently uses a custom asynctask (copied from jellybean) so you can use the executeOnExecutor in apis lower than < 11

http://developer.android.com/training/displaying-bitmaps/index.html

Download the code and go to util package.

What's the reason I can't create generic array types in Java?

Arrays Are Covariant

Arrays are said to be covariant which basically means that, given the subtyping rules of Java, an array of type T[] may contain elements of type T or any subtype of T. For instance

Number[] numbers = new Number[3];
numbers[0] = newInteger(10);
numbers[1] = newDouble(3.14);
numbers[2] = newByte(0);

But not only that, the subtyping rules of Java also state that an array S[] is a subtype of the array T[] if S is a subtype of T, therefore, something like this is also valid:

Integer[] myInts = {1,2,3,4};
Number[] myNumber = myInts;

Because according to the subtyping rules in Java, an array Integer[] is a subtype of an array Number[] because Integer is a subtype of Number.

But this subtyping rule can lead to an interesting question: what would happen if we try to do this?

myNumber[0] = 3.14; //attempt of heap pollution

This last line would compile just fine, but if we run this code, we would get an ArrayStoreException because we’re trying to put a double into an integer array. The fact that we are accessing the array through a Number reference is irrelevant here, what matters is that the array is an array of integers.

This means that we can fool the compiler, but we cannot fool the run-time type system. And this is so because arrays are what we call a reifiable type. This means that at run-time Java knows that this array was actually instantiated as an array of integers which simply happens to be accessed through a reference of type Number[].

So, as we can see, one thing is the actual type of the object, an another thing is the type of the reference that we use to access it, right?

The Problem with Java Generics

Now, the problem with generic types in Java is that the type information for type parameters is discarded by the compiler after the compilation of code is done; therefore this type information is not available at run time. This process is called type erasure. There are good reasons for implementing generics like this in Java, but that’s a long story, and it has to do with binary compatibility with pre-existing code.

The important point here is that since at run-time there is no type information, there is no way to ensure that we are not committing heap pollution.

Let’s consider now the following unsafe code:

List<Integer> myInts = newArrayList<Integer>();
myInts.add(1);
myInts.add(2);
List<Number> myNums = myInts; //compiler error
myNums.add(3.14); //heap polution

If the Java compiler does not stop us from doing this, the run-time type system cannot stop us either, because there is no way, at run time, to determine that this list was supposed to be a list of integers only. The Java run-time would let us put whatever we want into this list, when it should only contain integers, because when it was created, it was declared as a list of integers. That’s why the compiler rejects line number 4 because it is unsafe and if allowed could break the assumptions of the type system.

As such, the designers of Java made sure that we cannot fool the compiler. If we cannot fool the compiler (as we can do with arrays) then we cannot fool the run-time type system either.

As such, we say that generic types are non-reifiable, since at run time we cannot determine the true nature of the generic type.

I skipped some parts of this answers you can read full article here: https://dzone.com/articles/covariance-and-contravariance

yum error "Cannot retrieve metalink for repository: epel. Please verify its path and try again" updating ContextBroker

For boxes that does not have internet access, you can remove epel repository:

yum remove epel-release --disablerepo=epel

This happened to me as I accidentally installed epel-release using rpm on a prod box.

How to fix 'Notice: Undefined index:' in PHP form action

use isset for this purpose

<?php

 $index = 1;
 if(isset($_POST['filename'])) {
     $filename = $_POST['filename'];
     echo $filename;
 }

?>

How can I change the default credentials used to connect to Visual Studio Online (TFSPreview) when loading Visual Studio up?

After failing with cleaning the Credentials from the Manager and clearing the VS cache, consider to repair Visual Studio from the Visual Studio Installer (VS2017). I personally found no other solution working.

How to calculate UILabel width based on text length?

Here's something I came up with after applying a few principles other SO posts, including Aaron's link:

AnnotationPin *myAnnotation = (AnnotationPin *)annotation;

self = [super initWithAnnotation:myAnnotation reuseIdentifier:reuseIdentifier];
self.backgroundColor = [UIColor greenColor];
self.frame = CGRectMake(0,0,30,30);
imageView = [[UIImageView alloc] initWithImage:myAnnotation.THEIMAGE];
imageView.frame = CGRectMake(3,3,20,20);
imageView.layer.masksToBounds = NO;
[self addSubview:imageView];
[imageView release];

CGSize titleSize = [myAnnotation.THETEXT sizeWithFont:[UIFont systemFontOfSize:12]];
CGRect newFrame = self.frame;
newFrame.size.height = titleSize.height + 12;
newFrame.size.width = titleSize.width + 32;
self.frame = newFrame;
self.layer.borderColor = [UIColor colorWithRed:0 green:.3 blue:0 alpha:1.0f].CGColor;
self.layer.borderWidth = 3.0;
        
UILabel *infoLabel = [[UILabel alloc] initWithFrame:CGRectMake(26,5,newFrame.size.width-32,newFrame.size.height-12)];
infoLabel.text = myAnnotation.title;
infoLabel.backgroundColor = [UIColor clearColor];
infoLabel.textColor = [UIColor blackColor];
infoLabel.textAlignment = UITextAlignmentCenter;
infoLabel.font = [UIFont systemFontOfSize:12];

[self addSubview:infoLabel];
[infoLabel release];

In this example, I'm adding a custom pin to a MKAnnotation class that resizes a UILabel according to the text size. It also adds an image on the left side of the view, so you see some of the code managing the proper spacing to handle the image and padding.

The key is to use CGSize titleSize = [myAnnotation.THETEXT sizeWithFont:[UIFont systemFontOfSize:12]]; and then redefine the view's dimensions. You can apply this logic to any view.

Although Aaron's answer works for some, it didn't work for me. This is a far more detailed explanation that you should try immediately before going anywhere else if you want a more dynamic view with an image and resizable UILabel. I already did all the work for you!!

inherit from two classes in C#

Do you mean you want Class C to be the base class for A & B in that case.

public abstract class C
{
    public abstract void Method1();

    public abstract void Method2();
}

public class A : C
{
    public override void Method1()
    {
        throw new NotImplementedException();
    }

    public override void Method2()
    {
        throw new NotImplementedException();
    }
}


public class B : C
{
    public override void Method1()
    {
        throw new NotImplementedException();
    }

    public override void Method2()
    {
        throw new NotImplementedException();
    }
}

AngularJS - Any way for $http.post to send request parameters instead of JSON?

This might be a bit of a hack, but I avoided the issue and converted the json into PHP's POST array on the server side:

$_POST = json_decode(file_get_contents('php://input'), true);

What is JSONP, and why was it created?

Before understanding JSONP, you need to know JSON format and XML. Currently the most frequently used data format on the web is XML, but XML is very complicated. It makes users inconvenient to process embedded in Web pages.

To make JavaScript can easily exchange data, even as the data processing program, we use the wording according to JavaScript objects and developed a simple data exchange format, which is JSON. JSON can be used as data, or as a JavaScript program.

JSON can be directly embedded in JavaScript, using them you can directly execute certain JSON program, but due to security constraints, the browser Sandbox mechanism disables cross-domain JSON code execution.

To make JSON can be passed after the execution, we developed a JSONP. JSONP bypass the security limits of the browser with JavaScript Callback functionality and the < script > tag.

So in short it explains what JSONP is, what problem it solves (when to use it).

PostgreSQL naming conventions

Regarding tables names, case, etc, the prevalent convention is:

  • SQL keywords: UPPER CASE
  • names (identifiers): lower_case_with_underscores

For example:

UPDATE my_table SET name = 5;

This is not written in stone, but the bit about identifiers in lower case is highly recommended, IMO. Postgresql treats identifiers case insensitively when not quoted (it actually folds them to lowercase internally), and case sensitively when quoted; many people are not aware of this idiosyncrasy. Using always lowercase you are safe. Anyway, it's acceptable to use camelCase or PascalCase (or UPPER_CASE), as long as you are consistent: either quote identifiers always or never (and this includes the schema creation!).

I am not aware of many more conventions or style guides. Surrogate keys are normally made from a sequence (usually with the serial macro), it would be convenient to stick to that naming for those sequences if you create them by hand (tablename_colname_seq).

See also some discussion here, here and (for general SQL) here, all with several related links.

Note: Postgresql 10 introduced identity columns as an SQL-compliant replacement for serial.

CSS Positioning Elements Next to each other

If you want them to be displayed side by side, why is sideContent the child of mainContent? make them siblings then use:

float:left; display:inline; width: 49%;

on both of them.

#mainContent, #sideContent {float:left; display:inline; width: 49%;}

Is there a difference between using a dict literal and a dict constructor?

One big difference with python 3.4 + pycharm is that the dict() constructor produces a "syntax error" message if the number of keys exceeds 256.

I prefer using the dict literal now.

Facebook Post Link Image

If you used any plugin for seo then Check 1st your seo plugin settings.Then find out Noindex setting if Enable Media for Noindex then disable it.

How can I manually generate a .pyc file from a .py file

You can use compileall in the terminal. The following command will go recursively into sub directories and make pyc files for all the python files it finds. The compileall module is part of the python standard library, so you don't need to install anything extra to use it. This works exactly the same way for python2 and python3.

python -m compileall .

Carriage Return\Line feed in Java

Don't know who looks at your file, but if you open it in wordpad instead of notepad, the linebreaks will show correct. In case you're using a special file extension, associate it with wordpad and you're done with it. Or use any other more advanced text editor.

What is the "assert" function?

It is a function that will halt program execution if the value it has evaluated is false. Usually it is surrounded by a macro so that it is not compiled into the resultant binary when compiled with release settings.

It is designed to be used for testing the assumptions you have made. For example:

void strcpy(char* dest, char* src){
    //pointers shouldn't be null
    assert(dest!=null);
    assert(src!=null);

    //copy string
    while(*dest++ = *src++);
}

The ideal you want is that you can make an error in your program, like calling a function with invalid arguments, and you hit an assert before it segfaults (or fails to work as expected)

Python IndentationError unindent does not match any outer indentation level

I recently ran into the same problem but the issue wasn't related to tabs and spaces but an odd Unicode character that appeared invisible to the eye in my IDE. Eventually, I isolated the problem and typed out the line exactly as it was and checked the git diff:

enter image description here

If you are able to isolate the line before the reported line and type it out again, you might find that it solves your problem. Won't tell you why it happened in the first place, but it at least gets rid of the issue.

Converting double to integer in Java

Double perValue = 96.57;
int roundVal= (int) Math.round(perValue);

Solved my purpose.

jQuery disable a link

For others who came here via google like me - here's another approach:

css:
.disabled {
  color: grey; // ...whatever
}

jQuery:
$('#myLink').click(function (e) {
  e.preventDefault();
  if ($(this).hasClass('disabled'))
    return false; // Do something else in here if required
  else
    window.location.href = $(this).attr('href');
});

// Elsewhere in your code
if (disabledCondition == true)
  $('#myLink').addClass('disabled')
else
  $('#myLink').removeClass('disabled')

Remember: not only this is a css class

class="buttonstyle"

but also these two

class="buttonstyle disabled"

so you can easily add and remove further classes with jQuery. No need to touch href...

I love jQuery! ;-)

Testing if value is a function

I think the source of confusion is the distinction between a node's attribute and the corresponding property.

You're using:

$("a.button").parents("form").attr("onsubmit")

You're directly reading the onsubmit attribute's value (which must be a string). Instead, you should access the onsubmit property of the node:

$("a.button").parents("form").prop("onsubmit")

Here's a quick test:

<form id="form1" action="foo1.htm" onsubmit="return valid()"></form>
<script>
window.onload = function () {
    var form1 = document.getElementById("form1");

    function log(s) {
        document.write("<div>" + s + "</div>");
    }

    function info(v) {
        return "(" + typeof v + ") " + v;
    }

    log("form1 onsubmit property: " + info(form1.onsubmit));
    log("form1 onsubmit attribute: " + info(form1.getAttribute("onsubmit")));
};
</script> 

This yields:

form1 onsubmit property: (function) function onsubmit(event) { return valid(); }
form1 onsubmit attribute: (string) return valid()

AngularJS $resource RESTful example

$resource was meant to retrieve data from an endpoint, manipulate it and send it back. You've got some of that in there, but you're not really leveraging it for what it was made to do.

It's fine to have custom methods on your resource, but you don't want to miss out on the cool features it comes with OOTB.

EDIT: I don't think I explained this well enough originally, but $resource does some funky stuff with returns. Todo.get() and Todo.query() both return the resource object, and pass it into the callback for when the get completes. It does some fancy stuff with promises behind the scenes that mean you can call $save() before the get() callback actually fires, and it will wait. It's probably best just to deal with your resource inside of a promise then() or the callback method.

Standard use

var Todo = $resource('/api/1/todo/:id');

//create a todo
var todo1 = new Todo();
todo1.foo = 'bar';
todo1.something = 123;
todo1.$save();

//get and update a todo
var todo2 = Todo.get({id: 123});
todo2.foo += '!';
todo2.$save();

//which is basically the same as...
Todo.get({id: 123}, function(todo) {
   todo.foo += '!';
   todo.$save();
});

//get a list of todos
Todo.query(function(todos) {
  //do something with todos
  angular.forEach(todos, function(todo) {
     todo.foo += ' something';
     todo.$save();
  });
});

//delete a todo
Todo.$delete({id: 123});

Likewise, in the case of what you posted in the OP, you could get a resource object and then call any of your custom functions on it (theoretically):

var something = src.GetTodo({id: 123});
something.foo = 'hi there';
something.UpdateTodo();

I'd experiment with the OOTB implementation before I went and invented my own however. And if you find you're not using any of the default features of $resource, you should probably just be using $http on it's own.

Update: Angular 1.2 and Promises

As of Angular 1.2, resources support promises. But they didn't change the rest of the behavior.

To leverage promises with $resource, you need to use the $promise property on the returned value.

Example using promises

var Todo = $resource('/api/1/todo/:id');

Todo.get({id: 123}).$promise.then(function(todo) {
   // success
   $scope.todos = todos;
}, function(errResponse) {
   // fail
});

Todo.query().$promise.then(function(todos) {
   // success
   $scope.todos = todos;
}, function(errResponse) {
   // fail
});

Just keep in mind that the $promise property is a property on the same values it was returning above. So you can get weird:

These are equivalent

var todo = Todo.get({id: 123}, function() {
   $scope.todo = todo;
});

Todo.get({id: 123}, function(todo) {
   $scope.todo = todo;
});

Todo.get({id: 123}).$promise.then(function(todo) {
   $scope.todo = todo;
});

var todo = Todo.get({id: 123});
todo.$promise.then(function() {
   $scope.todo = todo;
});

Spring Boot: How can I set the logging level with application.properties?

You can try setting the log level to DEBUG it will show everything while starting the application

logging.level.root=DEBUG

Vue is not defined

jsBin demo

  1. You missed the order, first goes:

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/1.0.18/vue.min.js"></script>

and then:

<script>
    var demo = new Vue({
        el: '#demo',
        data: {
            message: 'Hello Vue.js!'
        }
    });
</script>
  1. And type="JavaScript" should be type="text/javascript" (or rather nothing at all)

Node.js: printing to console without a trailing newline?

As an expansion/enhancement to the brilliant addition made by @rodowi above regarding being able to overwrite a row:

process.stdout.write("Downloading " + data.length + " bytes\r");

Should you not want the terminal cursor to be located at the first character, as I saw in my code, the consider doing the following:

let dots = ''
process.stdout.write(`Loading `)

let tmrID = setInterval(() => {
  dots += '.'
  process.stdout.write(`\rLoading ${dots}`)
}, 1000)

setTimeout(() => {
  clearInterval(tmrID)
  console.log(`\rLoaded in [3500 ms]`)
}, 3500)

By placing the \r in front of the next print statement the cursor is reset just before the replacing string overwrites the previous.

Navigation Controller Push View Controller

UIViewController *vc=[self.storyboard instantiateViewControllerWithIdentifier:@"storyboardId"];
[self.navigationController pushViewController:vc animated:YES];

Can I change the checkbox size using CSS?

My understanding is that this isn't easy at all to do cross-browser. Instead of trying to manipulate the checkbox control, you could always build your own implementation using images, javascript, and hidden input fields. I'm assuming this is similar to what niceforms is (from Staicu lonut's answer above), but wouldn't be particularly difficult to implement. I believe jQuery has a plugin to allow for this custom behavior as well (will look for the link and post here if I can find it).

How to convert <font size="10"> to px?

the font size to em mapping is only accurate if there is no font-size defined and changes when your container is set to different sizes.

The following works best for me but it does not account for size=7 and anything above 7 only renders as 7.

font size=1 = font-size:x-small
font size=2 = font-size:small
font size=3 = font-size:medium
font size=4 = font-size:large
font size=5 = font-size:x-large
font size=6 = font-size:xx-large

enter image description here

Count immediate child div elements using jQuery

In response to mrCoders answer using jsperf why not just use the dom node ?

var $foo = $('#foo');
var count = $foo[0].childElementCount

You can try the test here: http://jsperf.com/jquery-child-ele-size/7

This method gets 46,095 op/s while the other methods at best 2000 op/s

What is the size limit of a post request?

By default, the post request has maximum size of 8mb. But you can modify it according to your requirements. The modification can be done by opening php.ini file (php configuration setting).

Find

post_max_size=8M  //for me, that was on line:771

replace 8 according to your requirements.

How to use Google App Engine with my own naked domain (not subdomain)?

Google does not provide an IP for us to set A record. If it would we could use naked domains.

There is another option, by setting A record to foreign web server's IP and that server could make an http redirect from e.g domain.com to www.domain.com (check out GiDNS)

How do I get the last character of a string?

Simple solution is:

public String frontBack(String str) {
  if (str == null || str.length() == 0) {
    return str;
  }
  char[] cs = str.toCharArray();
  char first = cs[0];
  cs[0] = cs[cs.length -1];
  cs[cs.length -1] = first;
  return new String(cs);
}

Using a character array (watch out for the nasty empty String or null String argument!)

Another solution uses StringBuilder (which is usually used to do String manupilation since String itself is immutable.

public String frontBack(String str) {
  if (str == null || str.length() == 0) {
    return str;
  }
  StringBuilder sb = new StringBuilder(str);  
  char first = sb.charAt(0);
  sb.setCharAt(0, sb.charAt(sb.length()-1));
  sb.setCharAt(sb.length()-1, first);
  return sb.toString();
}

Yet another approach (more for instruction than actual use) is this one:

public String frontBack(String str) {
  if (str == null || str.length() < 2) {
    return str;
  }
  StringBuilder sb = new StringBuilder(str);
  String sub = sb.substring(1, sb.length() -1);
  return sb.reverse().replace(1, sb.length() -1, sub).toString();
}

Here the complete string is reversed and then the part that should not be reversed is replaced with the substring. ;)

How do I dynamically assign properties to an object in TypeScript?

This solution is useful when your object has Specific Type. Like when obtaining the object to other source.

let user: User = new User();
(user as any).otherProperty = 'hello';
//user did not lose its type here.

Find the host name and port using PSQL commands

The default PostgreSQL port is 5432. The host that the database is operating on should have been provided by your hosting provider; I'd guess it would be the same host as the web server if one wasn't specified. Typically this would be configured as localhost, assuming your web server and database server are on the same host.

Number of lines in a file in Java

It seems that there are a few different approaches you can take with LineNumberReader.

I did this:

int lines = 0;

FileReader input = new FileReader(fileLocation);
LineNumberReader count = new LineNumberReader(input);

String line = count.readLine();

if(count.ready())
{
    while(line != null) {
        lines = count.getLineNumber();
        line = count.readLine();
    }
    
    lines+=1;
}
    
count.close();

System.out.println(lines);

Even more simply, you can use the Java BufferedReader lines() Method to return a stream of the elements, and then use the Stream count() method to count all of the elements. Then simply add one to the output to get the number of rows in the text file.

As example:

FileReader input = new FileReader(fileLocation);
LineNumberReader count = new LineNumberReader(input);

int lines = (int)count.lines().count() + 1;
    
count.close();

System.out.println(lines);

Linq to SQL .Sum() without group ... into

What about:

itemsInCart.AsEnumerable().Sum(o=>o.Price);

AsEnumerable makes the difference, this query will execute locally (Linq To Objects).

Adding blank spaces to layout

<View
    android:layout_width="fill_parent"
    android:layout_height="30dp"
    android:background="#80000000">
</View>

How do I list all the columns in a table?

Just a slight correction on the others in SQL Server (schema prefix is becoming more important!):

SELECT name
  FROM sys.columns 
  WHERE [object_id] = OBJECT_ID('dbo.tablename');

How do I remove the title bar from my app?

The easiest way: Just double click on this button and choose "NoTitleBar" ;)

Click here to see where it is :)

How to strip all whitespace from string

Remove the Starting Spaces in Python

string1="    This is Test String to strip leading space"
print string1
print string1.lstrip()

Remove the Trailing or End Spaces in Python

string2="This is Test String to strip trailing space     "
print string2
print string2.rstrip()

Remove the whiteSpaces from Beginning and end of the string in Python

string3="    This is Test String to strip leading and trailing space      "
print string3
print string3.strip()

Remove all the spaces in python

string4="   This is Test String to test all the spaces        "
print string4
print string4.replace(" ", "")

How to Convert date into MM/DD/YY format in C#

Have you tried the following?:

textbox1.text = System.DateTime.Today.ToString("MM/dd/yy");

Be aware that 2 digit years could be bad in the future...

How do you decrease navbar height in Bootstrap 3?

Instead of <nav class="navbar ... use <nav class="navbar navbar-xs...

and add these 3 line of css

.navbar-xs { min-height:28px; height: 28px; }
.navbar-xs .navbar-brand{ padding: 0px 12px;font-size: 16px;line-height: 28px; }
.navbar-xs .navbar-nav > li > a {  padding-top: 0px; padding-bottom: 0px; line-height: 28px; }

Output :

enter image description here

Function to check if a string is a date

In my project this seems to work:

function isDate($value) {
    if (!$value) {
        return false;
    } else {
        $date = date_parse($value);
        if($date['error_count'] == 0 && $date['warning_count'] == 0){
            return checkdate($date['month'], $date['day'], $date['year']);
        } else {
            return false;
        }
    }
}

Easy pretty printing of floats in python?

As of Python 3.6, you can use f-strings:

list_ = [9.0, 0.052999999999999999, 
         0.032575399999999997, 0.010892799999999999, 
         0.055702500000000002, 0.079330300000000006]

print(*[f"{element:.2f}" for element in list_])
#9.00 0.05 0.03 0.01 0.06 0.08

You can use print parameters while keeping code very readable:

print(*[f"{element:.2f}" for element in list_], sep='|', end='<--')
#9.00|0.05|0.03|0.01|0.06|0.08<--

How can I initialize a String array with length 0 in Java?

You can use ArrayUtils.EMPTY_STRING_ARRAY from org.apache.commons.lang3

import org.apache.commons.lang3.ArrayUtils;

    class Scratch {
        public static void main(String[] args) {
            String[] strings = ArrayUtils.EMPTY_STRING_ARRAY;
        }
    }

Debugging with Android Studio stuck at "Waiting For Debugger" forever

On some machines/projects the debugger do not attach automatically so you need to attach it manually (studio menu -> Run -> Attach debugger to Android process)

Using "margin: 0 auto;" in Internet Explorer 8

Add <!doctype html> at the top of your HTML output.

regular expression: match any word until first space

^([^\s]+) use this it correctly matches only the first word you can test this using this link https://regex101.com/

How to POST JSON request using Apache HttpClient?

As mentioned in the excellent answer by janoside, you need to construct the JSON string and set it as a StringEntity.

To construct the JSON string, you can use any library or method you are comfortable with. Jackson library is one easy example:

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;

ObjectMapper mapper = new ObjectMapper();
ObjectNode node = mapper.createObjectNode();
node.put("name", "value"); // repeat as needed
String JSON_STRING = node.toString();
postMethod.setEntity(new StringEntity(JSON_STRING, ContentType.APPLICATION_JSON));

How can I specify a display?

I faced similar problem today. So, here's a simple solution: While doing SSH to the machine, just add Ctrl - Y.

ssh user@ip_address -Y

After login, type firefox &. And you are good to go.

Git: How to squash all commits on branch

Based on reading several Stackoverflow questions and answers on squashing, I think this is a good one liner to squash all commits on a branch:

git reset --soft $(git merge-base master YOUR_BRANCH) && git commit -am "YOUR COMMIT MESSAGE" && git rebase -i master

This is assuming master is the base branch.

django order_by query set, ascending and descending

67

Reserved.objects.filter(client=client_id).order_by('-check_in')

'-' is indicates Descending order and for Ascending order just give class attribute

wamp server mysql user id and password

WAMP Server – MySQL – Resetting the Root Password (Windows)

  1. Log on to your system as Administrator.

  2. Click on the Wamp server icon > MySQL > MySQL Console

  3. Enter password: LEAVE BLANK AND HIT ENTER

  4. mysql> UPDATE mysql.user SET Password=PASSWORD(‘MyNewPass’) WHERE User=’root’; ENTER Query OK

  5. mysql>FLUSH PRIVILEGES; ENTER mysql>quit ENTER mysql>bye

  6. Edit phpmyadmin file called “config.inc.php” enter ‘MyNewPass’ ($cfg['Servers'][$i]['password'] = ‘MyNewPass‘;)

  7. Restart all services

  8. Clear all cookies – I got the No password error and it was because of the cookies. (ERROR 1045: Access denied for user: ‘root@localhost’ (Using password: NO))

Linux command line howto accept pairing for bluetooth device without pin

~ $ hciconfig noauth

It worked for me in "Linux mx 4.19"

The exact steps are:

1) open a terminal - run: "hciconfig noauth"
2) use the blueman-manager gui to pair the device (in my case it was a keyboard)
3) from the blueman-manager choose "connect to HID"

step(3) is normally asking for a password - the "hciconfig noauth" makes step(3) passwordless

javax vs java package

Some packages like javax.swing were not included in java standard library at first. Sun company decided to consider them official and included them into the early versions of java as standard libraries or standard extensions.

By convention, all the standard extensions start with an X while they can get promoted to first-class over time like what happened for javax.swing.

python replace single backslash with double backslash

Use:

string.replace(r"C:\Users\Josh\Desktop\20130216", "\\", "\\")

Escape the \ character.

How can I position my div at the bottom of its container?

Try this;

<div id="container">
  <div style="height: 100%; border:1px solid #ff0000;">
  <!-- Other elements here -->
  </div>
</div>
<div id="copyright" style="position:relative;border:1px solid #00ff00;top:-25px">
   Copyright Foo web designs
</div>

How to get year/month/day from a date object?

EUROPE (ENGLISH/SPANISH) FORMAT
I you need to get the current day too, you can use this one.

function getFormattedDate(today) 
{
    var week = new Array('Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday');
    var day  = week[today.getDay()];
    var dd   = today.getDate();
    var mm   = today.getMonth()+1; //January is 0!
    var yyyy = today.getFullYear();
    var hour = today.getHours();
    var minu = today.getMinutes();

    if(dd<10)  { dd='0'+dd } 
    if(mm<10)  { mm='0'+mm } 
    if(minu<10){ minu='0'+minu } 

    return day+' - '+dd+'/'+mm+'/'+yyyy+' '+hour+':'+minu;
}

var date = new Date();
var text = getFormattedDate(date);


*For Spanish format, just translate the WEEK variable.

var week = new Array('Domingo', 'Lunes', 'Martes', 'Miércoles', 'Jueves', 'Viernes', 'Sábado');


Output: Monday - 16/11/2015 14:24

Global variables in Javascript across multiple files

The variable can be declared in the .js file and simply referenced in the HTML file. My version of helpers.js:

var myFunctionWasCalled = false;

function doFoo()
{
    if (!myFunctionWasCalled) {
        alert("doFoo called for the very first time!");
        myFunctionWasCalled = true;
    }
    else {
        alert("doFoo called again");
    }
}

And a page to test it:

<html>
<head>
<title>Test Page</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
<script type="text/javascript" src="helpers.js"></script>
</head>

<body>


<p>myFunctionWasCalled is
<script type="text/javascript">document.write(myFunctionWasCalled);</script>
</p>

<script type="text/javascript">doFoo();</script>

<p>Some stuff in between</p>

<script type="text/javascript">doFoo();</script>

<p>myFunctionWasCalled is
<script type="text/javascript">document.write(myFunctionWasCalled);</script>
</p>

</body>
</html>

You'll see the test alert() will display two different things, and the value written to the page will be different the second time.

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:transformClassesWithDexForDebug'

Just a simple solution is here...it worked for me:

  1. Clean Project
  2. Rebuild project
  3. Sync project with gradle file

Vendor code 17002 to connect to SQLDeveloper

I encountered same problem with ORACLE 11G express on Windows. After a long time waiting I got the same error message.

My solution is to make sure the hostname in tnsnames.ora (usually it's not "localhost") and the default hostname in sql developer(usually it's "localhost") same. You can either do this by changing it in the tnsnames.ora, or filling up the same in the sql developer.

Oh, of course you need to reboot all the oracle services (just to be safe).

Hope it helps.


I came across the similar problem again on another machine, but this time above solution doesn't work. After some trying, I found restarting all the oracle related services can fix the problem. Originally when the installation is done, connection can be made. Somehow after several reboot of computer, there is problem. I change all the oracle services with start time as auto. And once I could not connect, I restart them all over again (the core service should be restarted at last order), and works fine.

Some article says it might be due to the MTS problem. Microsoft's problem. Maybe!

convert pfx format to p12

If you are looking for a quick and manual process with UI. I always use Mozilla Firefox to convert from PFX to P12. First import the certificate into the Firefox browser (Options > Privacy & Security > View Certificates... > Import...). Once installed, perform the export to create the P12 file by choosing the certificate name from the Certificate Manager and then click Backup... and enter the file name and then enter the password.

Rails - passing parameters in link_to

Try this

link_to "+ Service", my_services_new_path(:account_id => acct.id)

it will pass the account_id as you want.

For more details on link_to use this http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-link_to

How to truncate the time on a DateTime object in Python?

6 years later... I found this post and I liked more the numpy aproach:

import numpy as np
dates_array = np.array(['2013-01-01', '2013-01-15', '2013-01-30']).astype('datetime64[ns]')
truncated_dates = dates_array.astype('datetime64[D]')

cheers

Find element's index in pandas Series

Another way to do this, although equally unsatisfying is:

s = pd.Series([1,3,0,7,5],index=[0,1,2,3,4])

list(s).index(7)

returns: 3

On time tests using a current dataset I'm working with (consider it random):

[64]:    %timeit pd.Index(article_reference_df.asset_id).get_loc('100000003003614')
10000 loops, best of 3: 60.1 µs per loop

In [66]: %timeit article_reference_df.asset_id[article_reference_df.asset_id == '100000003003614'].index[0]
1000 loops, best of 3: 255 µs per loop


In [65]: %timeit list(article_reference_df.asset_id).index('100000003003614')
100000 loops, best of 3: 14.5 µs per loop

PostgreSQL "DESCRIBE TABLE"

The best way to describe a table such as a column, type, modifiers of columns, etc.

\d+ tablename or \d tablename

for or while loop to do something n times

The fundamental difference in most programming languages is that unless the unexpected happens a for loop will always repeat n times or until a break statement, (which may be conditional), is met then finish with a while loop it may repeat 0 times, 1, more or even forever, depending on a given condition which must be true at the start of each loop for it to execute and always false on exiting the loop, (for completeness a do ... while loop, (or repeat until), for languages that have it, always executes at least once and does not guarantee the condition on the first execution).

It is worth noting that in Python a for or while statement can have break, continue and else statements where:

  • break - terminates the loop
  • continue - moves on to the next time around the loop without executing following code this time around
  • else - is executed if the loop completed without any break statements being executed.

N.B. In the now unsupported Python 2 range produced a list of integers but you could use xrange to use an iterator. In Python 3 range returns an iterator.

So the answer to your question is 'it all depends on what you are trying to do'!

How can I solve a connection pool problem between ASP.NET and SQL Server?

Upon installing .NET Framework v4.6.1 our connections to a remote database immediately started timing out due to this change.

To fix simply add the parameter TransparentNetworkIPResolution in the connection string and set it to false:

Server=myServerName;Database=myDataBase;Trusted_Connection=True;TransparentNetworkIPResolution=False

C - reading command line parameters

When you write your main function, you typically see one of two definitions:

  • int main(void)
  • int main(int argc, char **argv)

The second form will allow you to access the command line arguments passed to the program, and the number of arguments specified (arguments are separated by spaces).

The arguments to main are:

  • int argc - the number of arguments passed into your program when it was run. It is at least 1.
  • char **argv - this is a pointer-to-char *. It can alternatively be this: char *argv[], which means 'array of char *'. This is an array of C-style-string pointers.

Basic Example

For example, you could do this to print out the arguments passed to your C program:

#include <stdio.h>

int main(int argc, char **argv)
{
    for (int i = 0; i < argc; ++i)
    {
        printf("argv[%d]: %s\n", i, argv[i]);
    }
}

I'm using GCC 4.5 to compile a file I called args.c. It'll compile and build a default a.out executable.

[birryree@lilun c_code]$ gcc -std=c99 args.c

Now run it...

[birryree@lilun c_code]$ ./a.out hello there
argv[0]: ./a.out
argv[1]: hello
argv[2]: there

So you can see that in argv, argv[0] is the name of the program you ran (this is not standards-defined behavior, but is common. Your arguments start at argv[1] and beyond.

So basically, if you wanted a single parameter, you could say...

./myprogram integral


A Simple Case for You

And you could check if argv[1] was integral, maybe like strcmp("integral", argv[1]) == 0.

So in your code...

#include <stdio.h>
#include <string.h>

int main(int argc, char **argv)
{
    if (argc < 2) // no arguments were passed
    {
        // do something
    }

    if (strcmp("integral", argv[1]) == 0)
    {
        runIntegral(...); //or something
    }
    else
    {
        // do something else.
    }
}

Better command line parsing

Of course, this was all very rudimentary, and as your program gets more complex, you'll likely want more advanced command line handling. For that, you could use a library like GNU getopt.

Error in plot.window(...) : need finite 'xlim' values

This error appears when the column contains character, if you check the data type it would be of type 'chr' converting the column to 'Factor' would solve this issue.

For e.g. In case you plot 'City' against 'Sales', you have to convert column 'City' to type 'Factor'

What does <? php echo ("<pre>"); ..... echo("</pre>"); ?> mean?

$testArray = [
[
  "name"   => "Dinesh Madusanka",
  "gender" => "male"
],
[
  "name"   => "Tharaka Devinda",
  "gender" => "male"
],
[
  "name"   => "Dumidu Ranasinghearachchi",
  "gender" => "male"
]


 ];

  print_r($testArray);

  echo "<pre>";
  print_r($testArray);

Angular 2 Sibling Component Communication

Updated to rc.4: When trying to get data passed between sibling components in angular 2, The simplest way right now (angular.rc.4) is to take advantage of angular2's hierarchal dependency injection and create a shared service.

Here would be the service:

import {Injectable} from '@angular/core';

@Injectable()
export class SharedService {
    dataArray: string[] = [];

    insertData(data: string){
        this.dataArray.unshift(data);
    }
}

Now, here would be the PARENT component

import {Component} from '@angular/core';
import {SharedService} from './shared.service';
import {ChildComponent} from './child.component';
import {ChildSiblingComponent} from './child-sibling.component';
@Component({
    selector: 'parent-component',
    template: `
        <h1>Parent</h1>
        <div>
            <child-component></child-component>
            <child-sibling-component></child-sibling-component>
        </div>
    `,
    providers: [SharedService],
    directives: [ChildComponent, ChildSiblingComponent]
})
export class parentComponent{

} 

and its two children

child 1

import {Component, OnInit} from '@angular/core';
import {SharedService} from './shared.service'

@Component({
    selector: 'child-component',
    template: `
        <h1>I am a child</h1>
        <div>
            <ul *ngFor="#data in data">
                <li>{{data}}</li>
            </ul>
        </div>
    `
})
export class ChildComponent implements OnInit{
    data: string[] = [];
    constructor(
        private _sharedService: SharedService) { }
    ngOnInit():any {
        this.data = this._sharedService.dataArray;
    }
}

child 2 (It's sibling)

import {Component} from 'angular2/core';
import {SharedService} from './shared.service'

@Component({
    selector: 'child-sibling-component',
    template: `
        <h1>I am a child</h1>
        <input type="text" [(ngModel)]="data"/>
        <button (click)="addData()"></button>
    `
})
export class ChildSiblingComponent{
    data: string = 'Testing data';
    constructor(
        private _sharedService: SharedService){}
    addData(){
        this._sharedService.insertData(this.data);
        this.data = '';
    }
}

NOW: Things to take note of when using this method.

  1. Only include the service provider for the shared service in the PARENT component and NOT the children.
  2. You still have to include constructors and import the service in the children
  3. This answer was originally answered for an early angular 2 beta version. All that has changed though are the import statements, so that is all you need to update if you used the original version by chance.

Center image horizontally within a div

_x000D_
_x000D_
.document {
  align-items: center;
  background-color: hsl(229, 57%, 11%);
  border-radius: 5px;
  display: flex;
  height: 40px;
  width: 40px;
}

.document img {
  display: block;
  margin: auto;
}
_x000D_
<div class="document">
  <img src="./images/icon-document.svg" alt="icon-document" />
</div>
_x000D_
_x000D_
_x000D_

Accessing Websites through a Different Port?

Unless you're browsing through a proxy, the web servers hosting the sites you want to access must be configured to listen to a port other than 80 or 8080.

Unresolved external symbol on static class members

Static data members declarations in the class declaration are not definition of them. To define them you should do this in the .CPP file to avoid duplicated symbols.

The only data you can declare and define is integral static constants. (Values of enums can be used as constant values as well)

You might want to rewrite your code as:

class test {
public:
  const static unsigned char X = 1;
  const static unsigned char Y = 2;
  ...
  test();
};

test::test() {
}

If you want to have ability to modify you static variables (in other words when it is inappropriate to declare them as const), you can separate you code between .H and .CPP in the following way:

.H :

class test {
public:

  static unsigned char X;
  static unsigned char Y;

  ...

  test();
};

.CPP :

unsigned char test::X = 1;
unsigned char test::Y = 2;

test::test()
{
  // constructor is empty.
  // We don't initialize static data member here, 
  // because static data initialization will happen on every constructor call.
}

How to convert a String to Bytearray

Since I cannot comment on the answer, I'd build on Jin Izzraeel's answer

var myBuffer = [];
var str = 'Stack Overflow';
var buffer = new Buffer(str, 'utf16le');
for (var i = 0; i < buffer.length; i++) {
    myBuffer.push(buffer[i]);
}

console.log(myBuffer);

by saying that you could use this if you want to use a Node.js buffer in your browser.

https://github.com/feross/buffer

Therefore, Tom Stickel's objection is not valid, and the answer is indeed a valid answer.

Apply CSS rules if browser is IE

A good way to avoid loading multiple CSS files or to have inline CSS is to hand a class to the body tag depending on the version of Internet Explorer. If you only need general IE hacks, you can do something like this, but it can be extended to be version specific:

<!--[if IE ]><body class="ie"><![endif]-->
<!--[if !IE]>--><body><!--<![endif]-->

Now in your css code, you can simply do:

.ie .abc {
  position:absolute;
  left:30;
  top:-10;
}

This also keeps your CSS files valid, as you do not have to use dirty (and invalid) CSS hacks.

How to convert column with dtype as object to string in Pandas Dataframe

since strings data types have variable length, it is by default stored as object dtype. If you want to store them as string type, you can do something like this.

df['column'] = df['column'].astype('|S80') #where the max length is set at 80 bytes,

or alternatively

df['column'] = df['column'].astype('|S') # which will by default set the length to the max len it encounters

How to convert the ^M linebreak to 'normal' linebreak in a file opened in vim?

On Solaris:

:%s/<CTRL+V><CTRL+M>//g

that is:

:%s/^M//g

That means:

  • % = all lines,
  • s = substitute,
  • ^M = what you desire to substitute
  • // = replace with nothing
  • g = globally (not only the first occurrance)

jQuery datepicker to prevent past date

I am using following code to format date and show 2 months in calendar...

<script>
$(function() {

    var dates = $( "#from, #to" ).datepicker({

        showOn: "button",
        buttonImage: "imgs/calendar-month.png",
        buttonImageOnly: true,                           
        defaultDate: "+1w",
        changeMonth: true,
        numberOfMonths: 2,

        onSelect: function( selectedDate ) {




            $( ".selector" ).datepicker({ defaultDate: +7 });
            var option = this.id == "from" ? "minDate" : "maxDate",


                instance = $( this ).data( "datepicker" ),
                date = $.datepicker.parseDate(
                    instance.settings.dateFormat ||
                    $.datepicker._defaults.dateFormat,
                    selectedDate, instance.settings );

            dates.not( this ).datepicker( "option", "dateFormat", 'yy-mm-dd' );


        }
    });
});

</script>

The problem is I am not sure how to restrict previous dates selection.

How to convert a single char into an int

#include<iostream>
#include<stdlib>
using namespace std;

void main()
{
     char ch;
     int x;
     cin >> ch;
     x = char (ar[1]);
     cout << x;
}

How to force reloading php.ini file?

You also can use graceful restart the apache server with service apache2 reload or apachectl -k graceful. As the apache doc says:

The USR1 or graceful signal causes the parent process to advise the children to exit after their current request (or to exit immediately if they're not serving anything). The parent re-reads its configuration files and re-opens its log files. As each child dies off the parent replaces it with a child from the new generation of the configuration, which begins serving new requests immediately.

How to customize listview using baseadapter

I suggest using a custom Adapter, first create a Xml-file, for example layout/customlistview.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="wrap_content" >
    <ImageView
        android:id="@+id/image"
        android:layout_alignParentRight="true"
        android:paddingRight="4dp" />
    <TextView
        android:id="@+id/title"
        android:layout_toLeftOf="@id/image"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="23sp"
        android:maxLines="1" />
    <TextView
        android:id="@+id/subtitle"
        android:layout_toLeftOf="@id/image" android:layout_below="@id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" /> 
</RelativeLayout>

Assuming you have a custom class like this

public class CustomClass {

    private long id;
    private String title, subtitle, picture;

    public CustomClass () {
    }

    public CustomClass (long id, String title, String subtitle, String picture) {
        this.id = id;
        this.title= title;
        this.subtitle= subtitle;
        this.picture= picture;
    }
    //add getters and setters
}

And a CustomAdapter.java uses the xml-layout

public class CustomAdapter extends ArrayAdapter {

private Context context;
private int resource;
private LayoutInflater inflater;

public CustomAdapter (Context context, List<CustomClass> values) { // or String[][] or whatever

    super(context, R.layout.customlistviewitem, values);

    this.context = context;
    this.resource = R.layout.customlistview;
    this.inflater = LayoutInflater.from(context);
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    convertView = (RelativeLayout) inflater.inflate(resource, null);

    CustomClass item = (CustomClass) getItem(position);

    TextView textviewTitle = (TextView) convertView.findViewById(R.id.title);
    TextView textviewSubtitle = (TextView) convertView.findViewById(R.id.subtitle);
    ImageView imageview = (ImageView) convertView.findViewById(R.id.image);

    //fill the textviews and imageview with the values
    textviewTitle = item.getTtile();
    textviewSubtitle = item.getSubtitle();

    if (item.getAfbeelding() != null) {
        int imageResource = context.getResources().getIdentifier("drawable/" + item.getImage(), null, context.getPackageName());
        Drawable image = context.getResources().getDrawable(imageResource);
    }
    imageview.setImageDrawable(image);

    return convertView;
    }
}

Did you manage to do it? Feel free to ask if you want more info on something :)

EDIT: Changed the adapter to suit a List instead of just a List

Execute SQL script from command line

If you want to run the script file then use below in cmd

sqlcmd -U user -P pass  -S servername -d databasename -i "G:\Hiren\Lab_Prodution.sql"

How to display an image from a path in asp.net MVC 4 and Razor view?

you can also try with this answer :

 <img src="~/Content/img/@Html.DisplayFor(model =>model.ImagePath)" style="height:200px;width:200px;"/>

Angular.js vs Knockout.js vs Backbone.js

It depends on the nature of your application. And, since you did not describe it in great detail, it is an impossible question to answer. I find Backbone to be the easiest, but I work in Angular all day. Performance is more up to the coder than the framework, in my opinion.

Are you doing heavy DOM manipulation? I would use jQuery and Backbone.

Very data driven app? Angular with its nice data binding.

Game programming? None - direct to canvas; maybe a game engine.

how to change namespace of entire project?

When I wanted to change namespace and the solution name I did as follows:
1) changed the namespace by selecting it and renaming it and I did the same with solution name
2) clicked on the light bulb and renamed all the instances of old namespace
3) removed all the projects from the solution
4) closed the visual studio
5) renamed all the projects in windows explorer
6) opened visual studio and added all the projects again
7) rename namespaces in all projects in their properties
8) removed bin folder (from all projects)
9) build the project again

That worked for me without any problems and my project had as well source control. All was fine after pushing those changes to the remote.

Creating for loop until list.length

The answer depends on what do you need a loop for.

of course you can have a loop similar to Java:

for i in xrange(len(my_list)):

but I never actually used loops like this,

because usually you want to iterate

for obj in my_list

or if you need an index as well

for index, obj in enumerate(my_list)

or you want to produce another collection from a list

map(some_func, my_list)

[somefunc[x] for x in my_list]

also there are itertools module that covers most of iteration related cases

also please take a look at the builtins like any, max, min, all, enumerate

I would say - do not try to write Java-like code in python. There is always a pythonic way to do it.

How to automate drag & drop functionality using Selenium WebDriver Java

Selenium has pretty good documentation. Here is a link to the specific part of the API you are looking for.

WebElement element = driver.findElement(By.name("source")); 

WebElement target = driver.findElement(By.name("target"));

(new Actions(driver)).dragAndDrop(element, target).perform();

Use of def, val, and var in scala

I'd start by the distinction that exists in Scala between def, val and var.

  • def - defines an immutable label for the right side content which is lazily evaluated - evaluate by name.

  • val - defines an immutable label for the right side content which is eagerly/immediately evaluated - evaluated by value.

  • var - defines a mutable variable, initially set to the evaluated right side content.

Example, def

scala> def something = 2 + 3 * 4 
something: Int
scala> something  // now it's evaluated, lazily upon usage
res30: Int = 14

Example, val

scala> val somethingelse = 2 + 3 * 5 // it's evaluated, eagerly upon definition
somethingelse: Int = 17

Example, var

scala> var aVariable = 2 * 3
aVariable: Int = 6

scala> aVariable = 5
aVariable: Int = 5

According to above, labels from def and val cannot be reassigned, and in case of any attempt an error like the below one will be raised:

scala> something = 5 * 6
<console>:8: error: value something_= is not a member of object $iw
       something = 5 * 6
       ^

When the class is defined like:

scala> class Person(val name: String, var age: Int)
defined class Person

and then instantiated with:

scala> def personA = new Person("Tim", 25)
personA: Person

an immutable label is created for that specific instance of Person (i.e. 'personA'). Whenever the mutable field 'age' needs to be modified, such attempt fails:

scala> personA.age = 44
personA.age: Int = 25

as expected, 'age' is part of a non-mutable label. The correct way to work on this consists in using a mutable variable, like in the following example:

scala> var personB = new Person("Matt", 36)
personB: Person = Person@59cd11fe

scala> personB.age = 44
personB.age: Int = 44    // value re-assigned, as expected

as clear, from the mutable variable reference (i.e. 'personB') it is possible to modify the class mutable field 'age'.

I would still stress the fact that everything comes from the above stated difference, that has to be clear in mind of any Scala programmer.

Reading Datetime value From Excel sheet

Or you can simply use OleDbDataAdapter to get data from Excel

Relative paths based on file location instead of current working directory

Just one line will be OK.

cat "`dirname $0`"/../some.txt

How do you move a file?

i think in the svn browser in tortoisesvn you can just drag it from one place to another.

Difference between a user and a schema in Oracle?

Schema is an encapsulation of DB.objects about an idea/domain of intrest, and owned by ONE user. It then will be shared by other users/applications with suppressed roles. So users need not own a schema, but a schema needs to have an owner.

Visual Studio keyboard shortcut to automatically add the needed 'using' statement

It's ctrl + . when, for example, you try to type List you need to type < at the end and press ctrl + . for it to work.

FFT in a single C-file

You could start converting this java snippet to C the author states he has converted it from C based on the book numerical recipies which you find online! here

How to get default gateway in Mac OSX

For getting the list of ip addresses associated, you can use netstat command

netstat -rn 

This gives a long list of ip addresses and it is not easy to find the required field. The sample result is as following:

Routing tables
Internet:
Destination        Gateway            Flags        Refs      Use   Netif Expire
default            192.168.195.1      UGSc           17        0     en2
127                127.0.0.1          UCS             0        0     lo0
127.0.0.1          127.0.0.1          UH              1   254107     lo0
169.254            link#7             UCS             0        0     en2
192.168.195        link#7             UCS             3        0     en2
192.168.195.1      0:27:22:67:35:ee   UHLWIi         22      397     en2   1193
192.168.195.5      127.0.0.1          UHS             0        0     lo0

More result is truncated.......

The ip address of gateway is in the first line; one with default at its first column.

To display only the selected lines of result, we can use grep command along with netstat

netstat -rn | grep 'default'

This command filters and displays those lines of result having default. In this case, you can see result like following:

default            192.168.195.1      UGSc           14        0     en2

If you are interested in finding only the ip address of gateway and nothing else you can further filter the result using awk. The awk command matches pattern in the input result and displays the output. This can be useful when you are using your result directly in some program or batch job.

netstat -rn | grep 'default' | awk '{print $2}'

The awk command tells to match and print the second column of the result in the text. The final result thus looks like this:

192.168.195.1

In this case, netstat displays all result, grep only selects the line with 'default' in it, and awk further matches the pattern to display the second column in the text.

You can similarly use route -n get default command to get the required result. The full command is

route -n get default | grep 'gateway' | awk '{print $2}'

These commands work well in linux as well as unix systems and MAC OS.

android splash screen sizes for ldpi,mdpi, hdpi, xhdpi displays ? - eg : 1024X768 pixels for ldpi

For Android Mobile Devices

LDPI- icon-36x36, splash-426x320 (now with correct values)


MDPI- icon-48x48, splash-470x320


HDPI- icon 72x72, splash- 640x480


XHDPI- icon-96x96, splash- 960x720


XXHDPI- icon- 144x144

All in pixels.

For Android Tablet Devices

LDPI:
    Portrait: 200x320px
    Landscape: 320x200px
MDPI:
    Portrait: 320x480px
    Landscape: 480x320px
HDPI:
    Portrait: 480x800px
    Landscape: 800x480px
XHDPI:
    Portrait: 720px1280px
    Landscape: 1280x720px

Visual Studio: Relative Assembly References Paths

I might be off here, but it seems that the answer is quite obvious: Look at reference paths in the project properties. In our setup I added our common repository folder, to the ref path GUI window, like so

Reference Paths in VS20xx

That way I can copy my dlls (ready for publish) to this folder and every developer now gets the updated DLL every time it builds from this folder.

If the dll is found in the Solution, the builder should prioritize the local version over the published team version.

Array initializing in Scala

If you know Array's length but you don't know its content, you can use

val length = 5
val temp = Array.ofDim[String](length)

If you want to have two dimensions array but you don't know its content, you can use

val row = 5
val column = 3
val temp = Array.ofDim[String](row, column)

Of course, you can change String to other type.

If you already know its content, you can use

val temp = Array("a", "b")

How can I prevent the backspace key from navigating back?

Have you tried the very simple solution of just adding the following attribute to your read only text field:

onkeydown="return false;"

This will keep the browser from going back in history when the Backspace key is pressed in a read only text field. Maybe I am missing your true intent, but seems like this would be the simplest solution to your issue.

Rotating videos with FFmpeg

Since ffmpeg transpose command is very slow, use the command below to rotate a video by 90 degrees clockwise.

Fast command (Without encoding)-

ffmpeg -i input.mp4 -c copy -metadata:s:v:0 rotate=270 output.mp4

For full video encoding (Slow command, does encoding)

ffmpeg -i inputFile -vf "transpose=1" -c:a copy outputFile

ASP.NET MVC 3 Razor: Include JavaScript file in the head tag

You can use Named Sections.

_Layout.cshtml

<head>
    <script type="text/javascript" src="@Url.Content("/Scripts/jquery-1.6.2.min.js")"></script>
    @RenderSection("JavaScript", required: false)
</head>

_SomeView.cshtml

@section JavaScript
{
   <script type="text/javascript" src="@Url.Content("/Scripts/SomeScript.js")"></script>
   <script type="text/javascript" src="@Url.Content("/Scripts/AnotherScript.js")"></script>
}

Google Maps API v3 adding an InfoWindow to each marker

Try this:

for (var i in tracks[racer_id].data.points) {
    values = tracks[racer_id].data.points[i];                
    point = new google.maps.LatLng(values.lat, values.lng);
    if (values.qst) {
        var marker = new google.maps.Marker({map: map, position: point, clickable: true});
        tracks[racer_id].markers[i] = marker;
        var info = new google.maps.InfoWindow({
            content: '<b>Speed:</b> ' + values.inst + ' knots'
        });
        tracks[racer_id].info[i] = info;
        google.maps.event.addListener(tracks[racer_id].markers[i], 'click', function() {
            tracks[racer_id].info[i].open(map, tracks[racer_id].markers[i]);
        });
    }
    track_coordinates.push(point);
    bd.extend(point);
}

Maximum concurrent Socket.IO connections

I tried to use socket.io on AWS, I can at most keep around 600 connections stable.

And I found out it is because socket.io used long polling first and upgraded to websocket later.

after I set the config to use websocket only, I can keep around 9000 connections.

Set this config at client side:

const socket = require('socket.io-client')
const conn = socket(host, { upgrade: false, transports: ['websocket'] })

How to type ":" ("colon") in regexp?

Be careful, - has a special meaning with regexp. In a [], you can put it without problem if it is placed at the end. In your case, ,-: is taken as from , to :.

Display number with leading zeros

df['Col1']=df['Col1'].apply(lambda x: '{0:0>5}'.format(x))

The 5 is the number of total digits.

I used this link: http://www.datasciencemadesimple.com/add-leading-preceding-zeros-python/

A Space between Inline-Block List Items

Another solution, similar to Gerbus' solution, but this also works with relative font sizing.

ul {
    letter-spacing: -1em; /* Effectively collapses white-space */
}
ul li {
    display: inline;
    letter-spacing: normal; /* Reset letter-spacing to normal value */
}

Does `anaconda` create a separate PYTHONPATH variable for each new environment?

No, the only thing that needs to be modified for an Anaconda environment is the PATH (so that it gets the right Python from the environment bin/ directory, or Scripts\ on Windows).

The way Anaconda environments work is that they hard link everything that is installed into the environment. For all intents and purposes, this means that each environment is a completely separate installation of Python and all the packages. By using hard links, this is done efficiently. Thus, there's no need to mess with PYTHONPATH because the Python binary in the environment already searches the site-packages in the environment, and the lib of the environment, and so on.

How to make a whole 'div' clickable in html and css without JavaScript?

My solution without JavaScript/images. Only CSS used. It works in all browsers.

HTML:

<a class="add_to_cart" href="https://www.redracingparts.com" title="Add to Cart!">
  buy now<br />free shipping<br />no further costs
</a>

CSS:

.add_to_cart:hover {
  background-color:#FF9933;
  text-decoration:none;
  color:#FFFFFF;
}

.add_to_cart {
  cursor:pointer;
  background-color:#EC5500;
  display:block;
  text-align:center;
  margin-top:8px;
  width:90px;
  height:31px;
  border-radius:5px;
  border-width:1px;
  border-style:solid;
  border-color:#E70000;
}

There is an example on https://www.redracingparts.com/english/motorbikesmotorcycles/stackoverflow/examples/div/clickable.php

Resize a picture to fit a JLabel

Outline

Here are the steps to follow.

  • Read the picture as a BufferedImage.
  • Resize the BufferedImage to another BufferedImage that's the size of the JLabel.
  • Create an ImageIcon from the resized BufferedImage.

You do not have to set the preferred size of the JLabel. Once you've scaled the image to the size you want, the JLabel will take the size of the ImageIcon.

Read the picture as a BufferedImage

BufferedImage img = null;
try {
    img = ImageIO.read(new File("strawberry.jpg"));
} catch (IOException e) {
    e.printStackTrace();
}

Resize the BufferedImage

Image dimg = img.getScaledInstance(label.getWidth(), label.getHeight(),
        Image.SCALE_SMOOTH);

Make sure that the label width and height are the same proportions as the original image width and height. In other words, if the picture is 600 x 900 pixels, scale to 100 X 150. Otherwise, your picture will be distorted.

Create an ImageIcon

ImageIcon imageIcon = new ImageIcon(dimg);

Select DataFrame rows between two dates

you can do it with pd.date_range() and Timestamp. Let's say you have read a csv file with a date column using parse_dates option:

df = pd.read_csv('my_file.csv', parse_dates=['my_date_col'])

Then you can define a date range index :

rge = pd.date_range(end='15/6/2020', periods=2)

and then filter your values by date thanks to a map:

df.loc[df['my_date_col'].map(lambda row: row.date() in rge)]

Set a default parameter value for a JavaScript function

If you are using ES6+ you can set default parameters in the following manner:

_x000D_
_x000D_
function test (foo = 1, bar = 2) {_x000D_
  console.log(foo, bar);_x000D_
}_x000D_
_x000D_
test(5); // foo gets overwritten, bar remains default parameter
_x000D_
_x000D_
_x000D_

If you need ES5 syntax you can do it in the following manner:

_x000D_
_x000D_
function test(foo, bar) {_x000D_
  foo = foo || 2;_x000D_
  bar = bar || 0;_x000D_
  _x000D_
  console.log(foo, bar);_x000D_
}_x000D_
_x000D_
test(5); // foo gets overwritten, bar remains default parameter
_x000D_
_x000D_
_x000D_

In the above syntax the OR operator is used. The OR operator always returns the first value if this can be converted to true if not it returns the righthandside value. When the function is called with no corresponding argument the parameter variable (bar in our example) is set to undefined by the JS engine. undefined Is then converted to false and thus does the OR operator return the value 0.

ClientScript.RegisterClientScriptBlock?

See if the below helps you:

I was using the following earlier:

ClientScript.RegisterClientScriptBlock(Page.GetType(), "AlertMsg", "<script language='javascript'>alert('The Web Policy need to be accepted to submit the new assessor information.');</script>");

After implementing AJAX in this page, it stopped working. After reading your blog, I changed the above to:

ScriptManager.RegisterClientScriptBlock(imgBtnSubmit, this.GetType(), "AlertMsg", "<script language='javascript'>alert('The Web Policy need to be accepted to submit the new assessor information.');</script>", false);

This is working perfectly fine.

(It’s .NET 2.0 Framework, I am using)

C# JSON Serialization of Dictionary into {key:value, ...} instead of {key:key, value:value, ...}

Unfortunately, this is not currently possible in the latest version of DataContractJsonSerializer. See: http://connect.microsoft.com/VisualStudio/feedback/details/558686/datacontractjsonserializer-should-serialize-dictionary-k-v-as-a-json-associative-array

The current suggested workaround is to use the JavaScriptSerializer as Mark suggested above.

Good luck!

Doing a cleanup action just before Node.js exits

function fnAsyncTest(callback) {
    require('fs').writeFile('async.txt', 'bye!', callback);
}

function fnSyncTest() {
    for (var i = 0; i < 10; i++) {}
}

function killProcess() {

    if (process.exitTimeoutId) {
        return;
    }

    process.exitTimeoutId = setTimeout(() => process.exit, 5000);
    console.log('process will exit in 5 seconds');

    fnAsyncTest(function() {
        console.log('async op. done', arguments);
    });

    if (!fnSyncTest()) {
        console.log('sync op. done');
    }
}

// https://nodejs.org/api/process.html#process_signal_events
process.on('SIGTERM', killProcess);
process.on('SIGINT', killProcess);

process.on('uncaughtException', function(e) {

    console.log('[uncaughtException] app will be terminated: ', e.stack);

    killProcess();
    /**
     * @https://nodejs.org/api/process.html#process_event_uncaughtexception
     *  
     * 'uncaughtException' should be used to perform synchronous cleanup before shutting down the process. 
     * It is not safe to resume normal operation after 'uncaughtException'. 
     * If you do use it, restart your application after every unhandled exception!
     * 
     * You have been warned.
     */
});

console.log('App is running...');
console.log('Try to press CTRL+C or SIGNAL the process with PID: ', process.pid);

process.stdin.resume();
// just for testing

Delete an element in a JSON object

with open('writing_file.json', 'w') as w:
    with open('reading_file.json', 'r') as r:
        for line in r:
            element = json.loads(line.strip())
            if 'hours' in element:
                del element['hours']
            w.write(json.dumps(element))

this is the method i use..

Hexadecimal To Decimal in Shell Script

Shortest way yet:

$ echo $[0x3F]
63