SyntaxFix

Programs & Examples On #Popup

In general, popup refers to any UI element that floats above a window or application surface. This may include tooltips, context menus, and modal dialog windows.

jQuery override default validation error message display (Css) Popup/Tooltip like

Unfortunately I can't comment with my newbie reputation, but I have a solution for the issue of the screen going blank, or at least this is what worked for me. Instead of setting the wrapper class inside of the errorPlacement function, set it immediately when you're setting the wrapper type. 

$('#myForm').validate({
    errorElement: "div",
    wrapper: "div class=\"message\"",
    errorPlacement: function(error, element) {
        offset = element.offset();
        error.insertBefore(element);
        //error.addClass('message');  // add a class to the wrapper
        error.css('position', 'absolute');
        error.css('left', offset.left + element.outerWidth() + 5);
        error.css('top', offset.top - 3);
    }

});

I'm assuming doing it this way allows the validator to know which div elements to remove, instead of all of them. Worked for me but I'm not entirely sure why, so if someone could elaborate that might help others out a ton.

jQuery: How can I show an image popup onclick of the thumbnail?

There are a lot of jQuery plugins available for this

Thickbox

LightBox

FancyBox

FaceBox

NyroModal

PiroBox

Thickbox Examples

For a single image

  1. Create a link element ()
  2. Give the link a class attribute with a value of thickbox (class="thickbox")
  3. Provide a path in the href attribute to an image file (.jpg .jpeg .png .gif .bmp)

How to handle authentication popup with Selenium WebDriver using Java

If you have to deal with NTLM proxy authentication a good alternative is to use a configure a local proxy using CNTLM.

The credentials and domain are configured in /etc/cntlm.conf.

Afterwards you can just use you own proxy that handles all the NTLM stuff. 

DesiredCapabilities capabilities = DesiredCapabilities.chrome();

Proxy proxy = new Proxy();
proxy.setHttpProxy("localhost:3128");
capabilities.setCapability(CapabilityType.PROXY, proxy);

driver = new ChromeDriver(capabilities);

How to make PopUp window in java

The same answer : JOptionpane with an example :) 

package experiments;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;

public class CreateDialogFromOptionPane {

    public static void main(final String[] args) {
        final JFrame parent = new JFrame();
        JButton button = new JButton();

        button.setText("Click me to show dialog!");
        parent.add(button);
        parent.pack();
        parent.setVisible(true);

        button.addActionListener(new java.awt.event.ActionListener() {
            @Override
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                String name = JOptionPane.showInputDialog(parent,
                        "What is your name?", null);
            }
        });
    }
}

enter image description here

How to handle Pop-up in Selenium WebDriver using Java

When the toastr message poped up on the screen of firefox. the below tag was displayed in fire bug. 

<div class="toast-message">Invalid Credentials, Please check Password</div>.

I took the screenshot at that time. And did the below changes in selenium java code.

String alertText = "";
WebDriverWait wait = new WebDriverWait(driver, 5);
wait.until(ExpectedConditions.visibilityOfElementLocated(By.className("toast-message")));
WebElement toast1 = driver.findElement(By.className("toast-message"));  
alertText = toast1.getText();
System.out.println( alertText);

And my issue of toastr popup got resolved.

Detecting the onload event of a window opened with window.open

The core problem seems to be you are opening a window to show a page whose content is already cached in the browser. Therefore no loading happens and therefore no load-event happens.

One possibility could be to use the 'pageshow' -event instead, as described in:

https://support.microsoft.com/en-us/help/3011939/onload-event-does-not-occur-when-clicking-the-back-button-to-a-previou

how to make window.open pop up Modal?

I was able to make parent window disable. However making the pop-up always keep raised didn't work. Below code works even for frame tags. Just add id and class property to frame tag and it works well there too.

In parent window use:

<head>    
<style>
.disableWin{
     pointer-events: none;
}
</style>
<script type="text/javascript">
    function openPopUp(url) {
      disableParentWin(); 
      var win = window.open(url);
      win.focus();
      checkPopUpClosed(win);
    }
    /*Function to detect pop up is closed and take action to enable parent window*/
   function checkPopUpClosed(win) {
         var timer = setInterval(function() {
              if(win.closed) {
                  clearInterval(timer);                  
                  enableParentWin();
              }
          }, 1000);
     }
     /*Function to enable parent window*/ 
     function enableParentWin() {
          window.document.getElementById('mainDiv').class="";
     }
     /*Function to enable parent window*/ 
     function disableParentWin() {
          window.document.getElementById('mainDiv').class="disableWin";
     }

</script>
</head>

<body>
<div id="mainDiv class="">
</div>
</body>

Show pop-ups the most elegant way

See http://adamalbrecht.com/2013/12/12/creating-a-simple-modal-dialog-directive-in-angular-js/ for a simple way of doing modal dialog with Angular and without needing bootstrap

Edit: I've since been using ng-dialog from http://likeastore.github.io/ngDialog which is flexible and doesn't have any dependencies.

javascript - pass selected value from popup window to parent window input box

(parent window) 

<html> 
<script language="javascript"> 
function openWindow() { 
  window.open("target.html","_blank","height=200,width=400, status=yes,toolbar=no,menubar=no,location=no"); 
} 
</script> 
<body> 
<form name=frm> 
<input id=text1 type=text> 
<input type=button onclick="javascript:openWindow()" value="Open window.."> 
</form> 
</body> 
</html>

(child window) 

<html> 
<script language="javascript"> 
function changeParent() { 
  window.opener.document.getElementById('text1').value="Value changed..";
  window.close();
} 
</script> 
<body> 
<form> 
<input type=button onclick="javascript:changeParent()" value="Change opener's textbox's value.."> 
</form> 
</body> 
</html>

http://www.codehappiness.com/post/access-parent-window-from-child-window-or-access-child-window-from-parent-window-using-javascript.aspx

Javascript Confirm popup Yes, No button instead of OK and Cancel

Have a look at http://bootboxjs.com/

Very easy to use:

 bootbox.confirm("Are you sure?", function(result) {
  Example.show("Confirm result: "+result);
});

Android Pop-up message

Suppose you want to set a pop-up text box for clicking a button lets say bt whose id is button, then code using Toast will somewhat look like this: 

Button bt;
bt = (Button) findViewById(R.id.button);
bt.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {            
Toast.makeText(getApplicationContext(),"The text you want to display",Toast.LENGTH_LONG)
}

Javascript Array Alert

If you want to see the array as an array, you can say

alert(JSON.stringify(aCustomers));

instead of all those document.writes.

http://jsfiddle.net/5b2eb/

However, if you want to display them cleanly, one per line, in your popup, do this:

alert(aCustomers.join("\n"));

http://jsfiddle.net/5b2eb/1/

Close popup window

In my case, I just needed to close my pop-up and redirect the user to his profile page when he clicks "ok" after reading some message I tried with a few hacks, including setTimeout + self.close(), but with IE, this was closing the whole tab...

Solution : I replaced my link with a simple submit button.
<button type="submit" onclick="window.location.href='profile.html';">buttonText</button>. Nothing more.

This may sound stupid, but I didn't think to such a simple solution, since my pop-up did not have any form.

I hope it will help some front-end noobs like me !

jQuery select element in parent window

Use the context-parameter 

$("#testdiv",parent.document)

But if you really use a popup, you need to access opener instead of parent

$("#testdiv",opener.document)

Display UIViewController as Popup in iPhone

Feel free to use my form sheet controller MZFormSheetControllerfor iPhone, in example project there are many examples on how to present modal view controller which will not cover full window and has many presentation/transition styles.

You can also try newest version of MZFormSheetController which is called MZFormSheetPresentationController and have a lot of more features.

How do I make a Mac Terminal pop-up/alert? Applescript?

This would restore focus to the previous application and exit the script if the answer was empty.

a=$(osascript -e 'try
tell app "SystemUIServer"
set answer to text returned of (display dialog "" default answer "")
end
end
activate app (path to frontmost application as text)
answer' | tr '\r' ' ')
[[ -z "$a" ]] && exit

If you told System Events to display the dialog, there would be a small delay if it wasn't running before.

For documentation about display dialog, open the dictionary of Standard Additions in AppleScript Editor or see the AppleScript Language Guide.

Simple Popup by using Angular JS

Built a modal popup example using syarul's jsFiddle link. Here is the updated fiddle.

Created an angular directive called modal and used in html. Explanation:-

HTML

<div ng-controller="MainCtrl" class="container">
  <button ng-click="toggleModal('Success')" class="btn btn-default">Success</button>
  <button ng-click="toggleModal('Remove')" class="btn btn-default">Remove</button>
  <button ng-click="toggleModal('Deny')" class="btn btn-default">Deny</button>
  <button ng-click="toggleModal('Cancel')" class="btn btn-default">Cancel</button>
  <modal visible="showModal">
      Any additional data / buttons
  </modal>
</div>

On button click toggleModal() function is called with the button message as parameter. This function toggles the visibility of popup. Any tags that you put inside will show up in the popup as content since ng-transclude is placed on modal-body in the directive template.

JS

var mymodal = angular.module('mymodal', []);

mymodal.controller('MainCtrl', function ($scope) {
    $scope.showModal = false;
    $scope.buttonClicked = "";
    $scope.toggleModal = function(btnClicked){
        $scope.buttonClicked = btnClicked;
        $scope.showModal = !$scope.showModal;
    };
  });

mymodal.directive('modal', function () {
    return {
      template: '<div class="modal fade">' + 
          '<div class="modal-dialog">' + 
            '<div class="modal-content">' + 
              '<div class="modal-header">' + 
                '<button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>' + 
                '<h4 class="modal-title">{{ buttonClicked }} clicked!!</h4>' + 
              '</div>' + 
              '<div class="modal-body" ng-transclude></div>' + 
            '</div>' + 
          '</div>' + 
        '</div>',
      restrict: 'E',
      transclude: true,
      replace:true,
      scope:true,
      link: function postLink(scope, element, attrs) {
        scope.title = attrs.title;

        scope.$watch(attrs.visible, function(value){
          if(value == true)
            $(element).modal('show');
          else
            $(element).modal('hide');
        });

        $(element).on('shown.bs.modal', function(){
          scope.$apply(function(){
            scope.$parent[attrs.visible] = true;
          });
        });

        $(element).on('hidden.bs.modal', function(){
          scope.$apply(function(){
            scope.$parent[attrs.visible] = false;
          });
        });
      }
    };
  });

UPDATE

<!doctype html>
<html ng-app="mymodal">


<body>

<div ng-controller="MainCtrl" class="container">
  <button ng-click="toggleModal('Success')" class="btn btn-default">Success</button>
  <button ng-click="toggleModal('Remove')" class="btn btn-default">Remove</button>
  <button ng-click="toggleModal('Deny')" class="btn btn-default">Deny</button>
  <button ng-click="toggleModal('Cancel')" class="btn btn-default">Cancel</button>
  <modal visible="showModal">
      Any additional data / buttons
  </modal>
</div>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.1/css/bootstrap.min.css">
        <!-- Scripts -->
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="http://netdna.bootstrapcdn.com/bootstrap/3.0.3/js/bootstrap.min.js"></script>

<script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.2.26/angular.min.js"></script>

    <!-- App -->
    <script>
        var mymodal = angular.module('mymodal', []);

mymodal.controller('MainCtrl', function ($scope) {
    $scope.showModal = false;
    $scope.buttonClicked = "";
    $scope.toggleModal = function(btnClicked){
        $scope.buttonClicked = btnClicked;
        $scope.showModal = !$scope.showModal;
    };
  });

mymodal.directive('modal', function () {
    return {
      template: '<div class="modal fade">' + 
          '<div class="modal-dialog">' + 
            '<div class="modal-content">' + 
              '<div class="modal-header">' + 
                '<button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>' + 
                '<h4 class="modal-title">{{ buttonClicked }} clicked!!</h4>' + 
              '</div>' + 
              '<div class="modal-body" ng-transclude></div>' + 
            '</div>' + 
          '</div>' + 
        '</div>',
      restrict: 'E',
      transclude: true,
      replace:true,
      scope:true,
      link: function postLink(scope, element, attrs) {
          scope.$watch(attrs.visible, function(value){
          if(value == true)
            $(element).modal('show');
          else
            $(element).modal('hide');
        });

        $(element).on('shown.bs.modal', function(){
          scope.$apply(function(){
            scope.$parent[attrs.visible] = true;
          });
        });

        $(element).on('hidden.bs.modal', function(){
          scope.$apply(function(){
            scope.$parent[attrs.visible] = false;
          });
        });
      }
    };
  });

    </script>
</body>
</html>

UPDATE 2 restrict : 'E' : directive to be used as an HTML tag (element). Example in our case is 

<modal>

Other values are 'A' for attribute 

<div modal>

'C' for class (not preferable in our case because modal is already a class in bootstrap.css)

<div class="modal">

Avoid browser popup blockers

Based on Jason Sebring's very useful tip, and on the stuff covered here and there, I found a perfect solution for my case:

Pseudo code with Javascript snippets:

  1. immediately create a blank popup on user action

     var importantStuff = window.open('', '_blank');

    (Enrich the call to window.open with whatever additional options you need.)

    Optional: add some "waiting" info message. Examples:

    a) An external HTML page: replace the above line with

     var importantStuff = window.open('http://example.com/waiting.html', '_blank');

    b) Text: add the following line below the above one:

     importantStuff.document.write('Loading preview...');

  2. fill it with content when ready (when the AJAX call is returned, for instance)

     importantStuff.location.href = 'https://example.com/finally.html';

    Alternatively, you could close the window here if you don't need it after all (if ajax request fails, for example - thanks to @Goose for the comment):

     importantStuff.close();

I actually use this solution for a mailto redirection, and it works on all my browsers (windows 7, Android). The _blank bit helps for the mailto redirection to work on mobile, btw.

how to implement a pop up dialog box in iOS

Although I already wrote an overview of different kinds of popups, most people just need an Alert.

How to implement a popup dialog box

enter image description here

class ViewController: UIViewController {

    @IBAction func showAlertButtonTapped(_ sender: UIButton) {

        // create the alert
        let alert = UIAlertController(title: "My Title", message: "This is my message.", preferredStyle: UIAlertController.Style.alert)

        // add an action (button)
        alert.addAction(UIAlertAction(title: "OK", style: UIAlertAction.Style.default, handler: nil))

        // show the alert
        self.present(alert, animated: true, completion: nil)
    }
}

My fuller answer is here.

Background blur with CSS

In which way do you want it dynamic? If you want the popup to successfully map to the background, you need to create two backgrounds. It requires both the use of element() or -moz-element() and a filter (for Firefox, use a SVG filter like filter: url(#svgBlur) since Firefox does not support -moz-filter: blur() as yet?). It only works in Firefox at the time of writing.

See demo here.

I still need to create a simple demo to show how it is done. You're welcome to view the source.

How to handle login pop up window using Selenium WebDriver?

Solution: Windows active directory authentication using Thread and Robot

I used Java Thread and Robot with Selenium webdriver to automate windows active directory authentication process of our website. This logic worked fine in Firefox and Chrome but it didn't work in IE. For some reason IE kills the webdriver when authentication window pops up whereas Chrome and Firefox prevents the web driver from getting killed. I didn't try in other web browser such as Safari.

//...
//Note: this logic works in Chrome and Firefox. It did not work in IE and I did not try Safari.
//...

//import relevant packages here

public class TestDemo {

    static WebDriver driver;

    public static void main(String[] args) {

        //setup web driver
        System.setProperty("webdriver.chrome.driver", "path to your chromedriver.exe");
        driver = new ChromeDriver();

        //create new thread for interaction with windows authentication window
        (new Thread(new LoginWindow())).start();                

        //open your url. this will prompt you for windows authentication
        driver.get("your url");

        //add test scripts below ...
        driver.findElement(By.linkText("Home")).click();    
        //.....
        //.....
    }

    //inner class for Login thread    
    public class LoginWindow implements Runnable {

        @Override
        public void run() {
            try {
                login();
            } catch (Exception ex) {
                System.out.println("Error in Login Thread: " + ex.getMessage());
            }
        }

        public void login() throws Exception {

            //wait - increase this wait period if required
            Thread.sleep(5000);

            //create robot for keyboard operations
            Robot rb = new Robot();

            //Enter user name by ctrl-v
            StringSelection username = new StringSelection("username");
            Toolkit.getDefaultToolkit().getSystemClipboard().setContents(username, null);            
            rb.keyPress(KeyEvent.VK_CONTROL);
            rb.keyPress(KeyEvent.VK_V);
            rb.keyRelease(KeyEvent.VK_V);
            rb.keyRelease(KeyEvent.VK_CONTROL);

            //tab to password entry field
            rb.keyPress(KeyEvent.VK_TAB);
            rb.keyRelease(KeyEvent.VK_TAB);
            Thread.sleep(2000);

            //Enter password by ctrl-v
            StringSelection pwd = new StringSelection("password");
            Toolkit.getDefaultToolkit().getSystemClipboard().setContents(pwd, null);
            rb.keyPress(KeyEvent.VK_CONTROL);
            rb.keyPress(KeyEvent.VK_V);
            rb.keyRelease(KeyEvent.VK_V);
            rb.keyRelease(KeyEvent.VK_CONTROL);

            //press enter
            rb.keyPress(KeyEvent.VK_ENTER);
            rb.keyRelease(KeyEvent.VK_ENTER);

            //wait
            Thread.sleep(5000);
        }                        
    }      
}

How to make popup look at the centre of the screen?

In order to get the popup exactly centered, it's a simple matter of applying a negative top margin of half the div height, and a negative left margin of half the div width. For this example, like so:

.div {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 50%;
}

Popup window in winform c#

"But the thing is I also want to be able to add textboxes etc in this popup window thru the form designer."

It's unclear from your description at what stage in the development process you're in. If you haven't already figured it out, to create a new Form you click on Project --> Add Windows Form, then type in a name for the form and hit the "Add" button. Now you can add controls to your form as you'd expect.

When it comes time to display it, follow the advice of the other posts to create an instance and call Show() or ShowDialog() as appropriate.

HTML / CSS Popup div on text click

DEMO

In the content area you can provide whatever you want to display in it.

_x000D_
_x000D_ 
.black_overlay {_x000D_
  display: none;_x000D_
  position: absolute;_x000D_
  top: 0%;_x000D_
  left: 0%;_x000D_
  width: 100%;_x000D_
  height: 100%;_x000D_
  background-color: black;_x000D_
  z-index: 1001;_x000D_
  -moz-opacity: 0.8;_x000D_
  opacity: .80;_x000D_
  filter: alpha(opacity=80);_x000D_
}_x000D_
.white_content {_x000D_
  display: none;_x000D_
  position: absolute;_x000D_
  top: 25%;_x000D_
  left: 25%;_x000D_
  width: 50%;_x000D_
  height: 50%;_x000D_
  padding: 16px;_x000D_
  border: 16px solid orange;_x000D_
  background-color: white;_x000D_
  z-index: 1002;_x000D_
  overflow: auto;_x000D_
}
_x000D_ 
<html>_x000D_
_x000D_
<head>_x000D_
  <title>LIGHTBOX EXAMPLE</title>_x000D_
</head>_x000D_
_x000D_
<body>_x000D_
  <p>This is the main content. To display a lightbox click <a href="javascript:void(0)" onclick="document.getElementById('light').style.display='block';document.getElementById('fade').style.display='block'">here</a>_x000D_
  </p>_x000D_
  <div id="light" class="white_content">This is the lightbox content. <a href="javascript:void(0)" onclick="document.getElementById('light').style.display='none';document.getElementById('fade').style.display='none'">Close</a>_x000D_
  </div>_x000D_
  <div id="fade" class="black_overlay"></div>_x000D_
</body>_x000D_
_x000D_
</html>
_x000D_
_x000D_
_x000D_

Open page in new window without popup blocking

 
function openLinkNewTab (url){
    $('body').append('<a id="openLinkNewTab" href="' + url + '" target="_blank"><span></span></a>').find('#openLinkNewTab span').click().remove();
}

How to generate a simple popup using jQuery

Here is a very simple popup:

<!DOCTYPE html>
<html>
    <head>
        <style>
            #modal {
                position:absolute;
                background:gray;
                padding:8px;
            }

            #content {
                background:white;
                padding:20px;
            }

            #close {
                position:absolute;
                background:url(close.png);
                width:24px;
                height:27px;
                top:-7px;
                right:-7px;
            }
        </style>
        <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
        <script>
            var modal = (function(){
                // Generate the HTML and add it to the document
                $modal = $('<div id="modal"></div>');
                $content = $('<div id="content"></div>');
                $close = $('<a id="close" href="#"></a>');

                $modal.hide();
                $modal.append($content, $close);

                $(document).ready(function(){
                    $('body').append($modal);                       
                });

                $close.click(function(e){
                    e.preventDefault();
                    $modal.hide();
                    $content.empty();
                });
                // Open the modal
                return function (content) {
                    $content.html(content);
                    // Center the modal in the viewport
                    $modal.css({
                        top: ($(window).height() - $modal.outerHeight()) / 2, 
                        left: ($(window).width() - $modal.outerWidth()) / 2
                    });
                    $modal.show();
                };
            }());

            // Wait until the DOM has loaded before querying the document
            $(document).ready(function(){
                $('a#popup').click(function(e){
                    modal("<p>This is popup's content.</p>");
                    e.preventDefault();
                });
            });
        </script>
    </head>
    <body>
        <a id='popup' href='#'>Simple popup</a>
    </body>
</html>

More flexible solution can be found in this tutorial: http://www.jacklmoore.com/notes/jquery-modal-tutorial/ Here's close.png for the sample.

Javascript to open popup window and disable parent window

To my knowledge, you cannot disable the browser window.

What you can do is create a jQuery (or a similar kind of ) popup and when this popup appears your parent browser will be disabled.

Open your child page in popup.

How to make a simple popup box in Visual C#?

In Visual Studio 2015 (community edition), System.Windows.Forms is not available and hence we can't use MessageBox.Show("text").

Use this Instead:

var Msg = new MessageDialog("Some String here", "Title of Message Box");    
await Msg.ShowAsync();

Note: Your function must be defined async to use above await Msg.ShowAsync().

Using JQuery to open a popup window and print

Got it! I found an idea here

http://www.mail-archive.com/[email protected]/msg18410.html

In this example, they loaded a blank popup window into an object, cloned the contents of the element to be displayed, and appended it to the body of the object. Since I already knew what the contents of view-details (or any page I load in the lightbox), I just had to clone that content instead and load it into an object. Then, I just needed to print that object. The final outcome looks like this:

$('.printBtn').bind('click',function() {
    var thePopup = window.open( '', "Customer Listing", "menubar=0,location=0,height=700,width=700" );
    $('#popup-content').clone().appendTo( thePopup.document.body );
    thePopup.print();
});

I had one small drawback in that the style sheet I was using in view-details.php was using a relative link. I had to change it to an absolute link. The reason being that the window didn't have a URL associated with it, so it had no relative position to draw on.

Works in Firefox. I need to test it in some other major browsers too.

I don't know how well this solution works when you're dealing with images, videos, or other process intensive solutions. Although, it works pretty well in my case, since I'm just loading tables and text values.

Thanks for the input! You gave me some ideas of how to get around this.

How do you add a scroll bar to a div?

Css class to have a nice Div with scroll

.DivToScroll{   
    background-color: #F5F5F5;
    border: 1px solid #DDDDDD;
    border-radius: 4px 0 4px 0;
    color: #3B3C3E;
    font-size: 12px;
    font-weight: bold;
    left: -1px;
    padding: 10px 7px 5px;
}

.DivWithScroll{
    height:120px;
    overflow:scroll;
    overflow-x:hidden;
}

How to open a WPF Popup when another control is clicked, using XAML markup only?

another way to do it:

<Border x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="true">
                    <StackPanel>
                        <Image Source="{Binding ProductImage,RelativeSource={RelativeSource TemplatedParent}}" Stretch="Fill" Width="65" Height="85"/>
                        <ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
                        <Button x:Name="myButton" Width="40" Height="10">
                            <Popup Width="100" Height="70" IsOpen="{Binding ElementName=myButton,Path=IsMouseOver, Mode=OneWay}">
                                <StackPanel Background="Yellow">
                                    <ItemsControl ItemsSource="{Binding Produkt.SubProducts}"/>
                                </StackPanel>
                            </Popup>
                        </Button>
                    </StackPanel>
                </Border>

Submit a form in a popup, and then close the popup

Try like this as well

covertPostSub("/xyz/test.jsp","?param1=param1&param2=param2","_self","true");
covertPostSub("/xyz/test.jsp","?param1=param1&param2=param2","_blank","true");

var convPop = null;
function covertPostSub(action,paramsTosend,targetIframe,isWindow){
    var Popup = null;
    var form = document.createElement("form");
    form.setAttribute("method", "POST");
    form.setAttribute("id","TheForm");
    form.setAttribute("action", action);
    form.setAttribute("target", targetIframe);
    var params = paramsTosend;
    params = params.substring(1, params.length);
    params = params.split("&");
    for(var key=0; key<params.length; key++) {
        var sa = params[key];
        sa = sa.split("=");
        var xs = (sa[1]);

        if(params.hasOwnProperty(key)) {
            var hiddenField = document.createElement("input");
            hiddenField.setAttribute("type", "hidden");
            hiddenField.setAttribute("name", sa[0]);
            hiddenField.setAttribute("value",xs);

            form.appendChild(hiddenField);
         }
    }
    document.body.appendChild(form);
    form.style.display = "none";
    if(isWindow){
        window.open('', "formpopup","width=900,height=590,toolbar=no,scrollbars=yes,resizable=no,location=0,directories=0,status=1,menubar=0,left=60,top=60");
        form.target = 'formpopup';
        form.submit();
    }else{
        form.submit();
    }

}

Why is Chrome showing a "Please Fill Out this Field" tooltip on empty fields?

You need to add the attribute "formnovalidate" to the control that is triggering the browser validation, e.g.:

<input type="image" id="fblogin" formnovalidate src="/images/facebook_connect.png">

How to make a Div appear on top of everything else on the screen?

One form to do this is insert the panel that you want to expand inside a DIV setted as relative: let me show you:

<div style="position:relative">
  <div style="position:absolute; z-index: 1000;">
    your code
  </div>
</div>

You use the first div to position the inner content in a specific area inside your page and the second absolute should be referred to the container (because is relative) The z-index in this case is referred also to container and if it higher that the container should be at top. You can put the style in a CSS class and change the size of the absolute div to expand it on hover or another action that you want to control.

I hope that this help

How can you create pop up messages in a batch script?

So, i present cmdmsg.bat.

The code is:

@echo off
echo WScript.Quit MsgBox(%1, vbYesNo) > #.vbs
cscript //nologo #.vbs
echo. >%ERRORLEVEL%.cm
del #.vbs
exit /b

And a example file:

@echo off 
cls 
call cmdmsg "hi select yes or no"

if exist "6.cm" call :yes
if exist "7.cm" call :no

:yes
cls
if exist "6.cm" del 6.cm
if exist "7.cm" del 7.cm
echo.
echo you selected yes
echo.
pause >nul
exit /b

:no
cls
if exist "6.cm" del 6.cm
if exist "7.cm" del 7.cm
echo.
echo aw man, you selected no
echo.
pause >nul
exit /b

Show popup after page load

try something like this

<script type="text/javascript">
function PopUp(hideOrshow) {
    if (hideOrshow == 'hide') document.getElementById('ac-wrapper').style.display = "none";
    else document.getElementById('ac-wrapper').removeAttribute('style');
}
window.onload = function () {
    setTimeout(function () {
        PopUp('show');
    }, 5000);
}
</script>

and your html

<div id="ac-wrapper" style='display:none'>
    <div id="popup">
        <center>
             <h2>Popup Content Here</h2>    
            <input type="submit" name="submit" value="Submit" onClick="PopUp('hide')" />
        </center>
    </div>
</div>

Demo JsFiddle

Alert handling in Selenium WebDriver (selenium 2) with Java

You could try

 try{
        if(webDriver.switchTo().alert() != null){
           Alert alert = webDriver.switchTo().alert();
           alert.getText();
           //etc.
        }
    }catch(Exception e){}

If that doesn't work, you could try looping through all the window handles and see if the alert exists. I'm not sure if the alert opens as a new window using selenium.

for(String s: webDriver.getWindowHandles()){
 //see if alert exists here.
}

Python list sort in descending order

you simple type:

timestamps.sort()
timestamps=timestamps[::-1]

How to use bootstrap-theme.css with bootstrap 3?

For an example of the css styles have a look at: http://getbootstrap.com/examples/theme/

If you want to see how the example looks without the bootstrap-theme.css file open up your browser developer tools and delete the link from the <head> of the example and then you can compare it.

I know this is an old question but posted it just in case anyone is looking for an example of how it looks like I was.

Update

bootstrap.css = main css framework (grids, basic styles, etc)

bootstrap-theme.css = extended styling (3D buttons, gradients etc). This file is optional and does not effect the functionality of bootstrap at all, it only enhances the appearance.

Update 2

With the release of v3.2.0 Bootstrap have added an option to view the theme css on the doc pages. If you go to one of the doc pages (css, components, javascript) you should see a "Preview theme" link at the bottom of the side nav which you can use to turn the theme css on and off.

Wireshark localhost traffic capture

On Windows platform, it is also possible to capture localhost traffic using Wireshark. What you need to do is to install the Microsoft loopback adapter, and then sniff on it.

How to remove CocoaPods from a project?

From terminal cd to move to the project folder. The below steps help to de-integrate the pod from the project

$ sudo gem install cocoapods-deintegrate cocoapods-clean
$ pod deintegrate
$ pod clean
$ rm Podfile

Then just open the project file and remove the Pod folder if it is still on the Project Explorer with red color. Build the project

setSupportActionBar toolbar cannot be applied to (android.widget.Toolbar) error

With the addition of androidx in Studio 3.0+ the Toolbar compatibility is now in a new library, accessible like this

import androidx.appcompat.widget.Toolbar

Getting "Skipping JaCoCo execution due to missing execution data file" upon executing JaCoCo

I have added a Maven/Java project with 1 Domain class with the following features:

  • Unit or Integration testing with the plugins Surefire and Failsafe.
  • Findbugs.
  • Test coverage via Jacoco.

Where are the Jacoco results? After testing and running 'mvn clean', you can find the results in 'target/site/jacoco/index.html'. Open this file in the browser.

Enjoy!

I tried to keep the project as simple as possible. The project puts many suggestions from these posts together in an example project. Thank you, contributors!

SQL ORDER BY multiple columns

Sorting in an ORDER BY is done by the first column, and then by each additional column in the specified statement.

For instance, consider the following data:

Column1    Column2
=======    =======
1          Smith
2          Jones
1          Anderson
3          Andrews

The query

SELECT Column1, Column2 FROM thedata ORDER BY Column1, Column2

would first sort by all of the values in Column1

and then sort the columns by Column2 to produce this:

Column1    Column2
=======    =======
1          Anderson
1          Smith
2          Jones
3          Andrews

In other words, the data is first sorted in Column1 order, and then each subset (Column1 rows that have 1 as their value) are sorted in order of the second column.

The difference between the two statements you posted is that the rows in the first one would be sorted first by prod_price (price order, from lowest to highest), and then by order of name (meaning that if two items have the same price, the one with the lower alpha value for name would be listed first), while the second would sort in name order only (meaning that prices would appear in order based on the prod_name without regard for price).

jQuery check if it is clicked or not

 
    <script type="text/javascript" src="jquery-1.6.1.min.js"></script>
<script type="text/javascript">
var val;
        $(document).ready(function () {
            $("#click").click(function () {
                val = 1;
                get();
                });
                });
          function get(){
            if (val == 1){
                alert(val);
                }

          }
</script>
    <table>
    <tr><td id='click'>ravi</td></tr>
    </table>

How do you use window.postMessage across domains?

Here is an example that works on Chrome 5.0.375.125.

The page B (iframe content):

<html>
    <head></head>
    <body>
        <script>
            top.postMessage('hello', 'A');
        </script>
    </body>
</html>

Note the use of top.postMessage or parent.postMessage not window.postMessage here

The page A:

<html>
<head></head>
<body>
    <iframe src="B"></iframe>
    <script>
        window.addEventListener( "message",
          function (e) {
                if(e.origin !== 'B'){ return; } 
                alert(e.data);
          },
          false);
    </script>
</body>
</html>

A and B must be something like http://domain.com

EDIT:

From another question, it looks the domains(A and B here) must have a / for the postMessage to work properly.

best practice to generate random token for forgot password

In PHP, use random_bytes(). Reason: your are seeking the way to get a password reminder token, and, if it is a one-time login credentials, then you actually have a data to protect (which is - whole user account)

So, the code will be as follows:

//$length = 78 etc
$token = bin2hex(random_bytes($length));

Update: previous versions of this answer was referring to uniqid() and that is incorrect if there is a matter of security and not only uniqueness. uniqid() is essentially just microtime() with some encoding. There are simple ways to get accurate predictions of the microtime() on your server. An attacker can issue a password reset request and then try through a couple of likely tokens. This is also possible if more_entropy is used, as the additional entropy is similarly weak. Thanks to @NikiC and @ScottArciszewski for pointing this out.

For more details see

Pattern matching using a wildcard

You can also use package data.table and it's Like function, details given below How to select R data.table rows based on substring match (a la SQL like)

Running Python code in Vim

I have this in my .vimrc file:

imap <F5> <Esc>:w<CR>:!clear;python %<CR>

When I'm done editing a Python script, I just press <F5>. The script is saved and then executed in a blank screen.

proper hibernate annotation for byte[]

What is the portable way to annotate a byte[] property?

It depends on what you want. JPA can persist a non annotated byte[]. From the JPA 2.0 spec:

11.1.6 Basic Annotation

The Basic annotation is the simplest type of mapping to a database column. The Basic annotation can be applied to a persistent property or instance variable of any of the following types: Java primitive, types, wrappers of the primitive types, java.lang.String, java.math.BigInteger, java.math.BigDecimal, java.util.Date, java.util.Calendar, java.sql.Date, java.sql.Time, java.sql.Timestamp, byte[], Byte[], char[], Character[], enums, and any other type that implements Serializable. As described in Section 2.8, the use of the Basic annotation is optional for persistent fields and properties of these types. If the Basic annotation is not specified for such a field or property, the default values of the Basic annotation will apply.

And Hibernate will map a it "by default" to a SQL VARBINARY (or a SQL LONGVARBINARY depending on the Column size?) that PostgreSQL handles with a bytea.

But if you want the byte[] to be stored in a Large Object, you should use a @Lob. From the spec:

11.1.24 Lob Annotation

A Lob annotation specifies that a persistent property or field should be persisted as a large object to a database-supported large object type. Portable applications should use the Lob annotation when mapping to a database Lob type. The Lob annotation may be used in conjunction with the Basic annotation or with the ElementCollection annotation when the element collection value is of basic type. A Lob may be either a binary or character type. The Lob type is inferred from the type of the persistent field or property and, except for string and character types, defaults to Blob.

And Hibernate will map it to a SQL BLOB that PostgreSQL handles with a oid .

Is this fixed in some recent version of hibernate?

Well, the problem is that I don't know what the problem is exactly. But I can at least say that nothing has changed since 3.5.0-Beta-2 (which is where a changed has been introduced)in the 3.5.x branch.

But my understanding of issues like HHH-4876, HHH-4617 and of PostgreSQL and BLOBs (mentioned in the javadoc of the PostgreSQLDialect) is that you are supposed to set the following property

hibernate.jdbc.use_streams_for_binary=false

if you want to use oid i.e. byte[] with @Lob (which is my understanding since VARBINARY is not what you want with Oracle). Did you try this?

As an alternative, HHH-4876 suggests using the deprecated PrimitiveByteArrayBlobType to get the old behavior (pre Hibernate 3.5).

References

  • JPA 2.0 Specification
    • Section 2.8 "Mapping Defaults for Non-Relationship Fields or Properties"
    • Section 11.1.6 "Basic Annotation"
    • Section 11.1.24 "Lob Annotation"

Resources

bash: mkvirtualenv: command not found

On Windows 10, to create the virtual environment, I replace "pip mkvirtualenv myproject" by "mkvirtualenv myproject" and that works well.

JQuery - Call the jquery button click event based on name property

You can use the name property for that particular element. For example to set a border of 2px around an input element with name xyz, you can use;

$(function() {
    $("input[name = 'xyz']").css("border","2px solid red");
})

DEMO

Angular 6 Material mat-select change method removed

I have this issue today with mat-option-group. The thing which solved me the problem is using in other provided event of mat-select : valueChange

I put here a little code for understanding : 

<mat-form-field >
  <mat-label>Filter By</mat-label>
  <mat-select  panelClass="" #choosedValue (valueChange)="doSomething1(choosedValue.value)"> <!-- (valueChange)="doSomething1(choosedValue.value)" instead of (change) or other event-->

    <mat-option >-- None --</mat-option>
      <mat-optgroup  *ngFor="let group of filterData" [label]="group.viewValue"
                    style = "background-color: #0c5460">
        <mat-option *ngFor="let option of group.options" [value]="option.value">
          {{option.viewValue}}
        </mat-option>
      </mat-optgroup>
  </mat-select>
</mat-form-field>

Mat Version:

"@angular/material": "^6.4.7",

Self-reference for cell, column and row in worksheet functions

I was looking for a solution to this and used the indirect one found on this page initially, but I found it quite long and clunky for what I was trying to do. After a bit of research, I found a more elegant solution (to my problem) using R1C1 notation - I think you can't mix different notation styles without using VBA though.

Depending on what you're trying to do with the self referenced cell, something like this example should get a cell to reference itself where the cell is F13:

Range("F13").FormulaR1C1 = "RC"

And you can then reference cells in relative positions to that cell such as - where your cell is F13 and you need to reference G12 from it.

Range("F13").FormulaR1C1 = "R[-1]C[1]"

You're essentially telling Excel to find F13 and then move down 1 row and up one column from that.

How this fit into my project was to apply a vlookup across a range where the lookup value was relative to each cell in the range without having to specify each lookup cell separately:

Sub Code()
    Dim Range1 As Range
    Set Range1 = Range("B18:B23")
        Range1.Locked = False
        Range1.FormulaR1C1 = "=IFERROR(VLOOKUP(RC[-1],DATABYCODE,2,FALSE),"""")"
        Range1.Locked = True
End Sub

My lookup value is the cell to the left of each cell (column -1) in my DIM'd range and DATABYCODE is the named range I'm looking up against.

Hope that makes a little sense? Thought it was worth throwing into the mix as another way to approach the problem.

How do I measure separate CPU core usage for a process?

The ps solution was nearly what I needed and with some bash thrown in does exactly what the original question asked for: to see per-core usage of specific processes

This shows per-core usage of multi-threaded processes too.

Use like: cpustat `pgrep processname` `pgrep otherprocessname` ...

#!/bin/bash

pids=()
while [ $# != 0 ]; do
        pids=("${pids[@]}" "$1")
        shift
done

if [ -z "${pids[0]}" ]; then
        echo "Usage: $0 <pid1> [pid2] ..."
        exit 1
fi

for pid in "${pids[@]}"; do
        if [ ! -e /proc/$pid ]; then
                echo "Error: pid $pid doesn't exist"
                exit 1
        fi
done

while [ true ]; do
        echo -e "\033[H\033[J"
        for pid in "${pids[@]}"; do
                ps -p $pid -L -o pid,tid,psr,pcpu,comm=
        done
        sleep 1
done

Note: These stats are based on process lifetime, not the last X seconds, so you'll need to restart your process to reset the counter.

Sorted array list in Java

Aioobe's approach is the way to go. I would like to suggest the following improvement over his solution though.

class SortedList<T> extends ArrayList<T> {

    public void insertSorted(T value) {
        int insertPoint = insertPoint(value);
        add(insertPoint, value);
    }

    /**
     * @return The insert point for a new value. If the value is found the insert point can be any
     * of the possible positions that keeps the collection sorted (.33 or 3.3 or 33.).
     */
    private int insertPoint(T key) {
        int low = 0;
        int high = size() - 1;

        while (low <= high) {
            int mid = (low + high) >>> 1;
            Comparable<? super T> midVal = (Comparable<T>) get(mid);
            int cmp = midVal.compareTo(key);

            if (cmp < 0)
                low = mid + 1;
            else if (cmp > 0)
                high = mid - 1;
            else {
                return mid; // key found
            }
        }

        return low;  // key not found
    }
}

aioobe's solution gets very slow when using large lists. Using the fact that the list is sorted allows us to find the insert point for new values using binary search.

I would also use composition over inheritance, something along the lines of 

SortedList<E> implements List<E>, RandomAccess, Cloneable, java.io.Serializable

How to replace text in a column of a Pandas dataframe?

For anyone else arriving here from Google search on how to do a string replacement on all columns (for example, if one has multiple columns like the OP's 'range' column): Pandas has a built in replace method available on a dataframe object.

df.replace(',', '-', regex=True)

Source: Docs

iPhone App Icons - Exact Radius?

Update (as of Jan. 2018) for App Icon requirements:

https://developer.apple.com/ios/human-interface-guidelines/icons-and-images/app-icon/

Keep icon corners square. The system applies a mask that rounds icon corners automatically.

Keep the background simple and avoid transparency. Make sure your icon is opaque, and don’t clutter the background. Give it a simple background so it doesn’t overpower other app icons nearby. You don’t need to fill the entire icon with content.

HttpServletRequest to complete URL

The HttpServletRequest has the following methods:

  • getRequestURL() - returns the part of the full URL before query string separator character ?
  • getQueryString() - returns the part of the full URL after query string separator character ?

So, to get the full URL, just do:

public static String getFullURL(HttpServletRequest request) {
    StringBuilder requestURL = new StringBuilder(request.getRequestURL().toString());
    String queryString = request.getQueryString();

    if (queryString == null) {
        return requestURL.toString();
    } else {
        return requestURL.append('?').append(queryString).toString();
    }
}

Convert date to datetime in Python

You can use datetime.combine(date, time); for the time, you create a datetime.time object initialized to midnight.

from datetime import date
from datetime import datetime

dt = datetime.combine(date.today(), datetime.min.time())

GridView sorting: SortDirection always Ascending

The way I did this is similar to the code that the accepted answer provided, bit is a bit different so I thought I would put it out there as well. Note that this sorting is being done to a DataTable before it is being bound to the GridView.DataSource.

Option One: Using ViewState

void DataGrid_Sorting(object sender, GridViewSortEventArgs e)
{
    if (e.SortExpression == (string)ViewState["SortColumn"])
    {
        // We are resorting the same column, so flip the sort direction
        e.SortDirection = 
            ((SortDirection)ViewState["SortColumnDirection"] == SortDirection.Ascending) ? 
            SortDirection.Descending : SortDirection.Ascending;
    }
    // Apply the sort
    this._data.DefaultView.Sort = e.SortExpression +
        (string)((e.SortDirection == SortDirection.Ascending) ? " ASC" : " DESC");
    ViewState["SortColumn"] = e.SortExpression;
    ViewState["SortColumnDirection"] = e.SortDirection;
}

Option Two: Using Session

Note that the following is being provided for legacy purposes in the event that you see it in the field, or that you are still supporting company systems that are targeting older browsers.

void DataGrid_Sorting(object sender, GridViewSortEventArgs e)
{
    if (e.SortExpression == (string)HttpContext.Current.Session["SortColumn"])
    {
        // We are resorting the same column, so flip the sort direction
        e.SortDirection = 
            ((SortDirection)HttpContext.Current.Session["SortColumnDirection"] == SortDirection.Ascending) ? 
            SortDirection.Descending : SortDirection.Ascending;
    }
    // Apply the sort
    this._data.DefaultView.Sort = e.SortExpression +
        (string)((e.SortDirection == SortDirection.Ascending) ? " ASC" : " DESC");
    HttpContext.Current.Session["SortColumn"] = e.SortExpression;
    HttpContext.Current.Session["SortColumnDirection"] = e.SortDirection;
}

When should I use GET or POST method? What's the difference between them?

I use GET when I'm retrieving information from a URL and POST when I'm sending information to a URL.

Git fatal: protocol 'https' is not supported

 You tried this:

clt + V

Just right click and click on paste

Hope this will work

$(window).scrollTop() vs. $(document).scrollTop()

I've just had some of the similar problems with scrollTop described here.

In the end I got around this on Firefox and IE by using the selector $('*').scrollTop(0);

Not perfect if you have elements you don't want to effect but it gets around the Document, Body, HTML and Window disparity. If it helps...

Setting and getting localStorage with jQuery

The localStorage can only store string content and you are trying to store a jQuery object since html(htmlString) returns a jQuery object.

You need to set the string content instead of an object. And use the setItem method to add data and getItem to get data.

window.localStorage.setItem('content', 'Test');
$('#test').html(window.localStorage.getItem('content'));

How to get files in a relative path in C#

 
string currentDirectory = Path.GetDirectoryName(Assembly.GetEntryAssembly().Location);
string archiveFolder = Path.Combine(currentDirectory, "archive");
string[] files = Directory.GetFiles(archiveFolder, "*.zip");

The first parameter is the path. The second is the search pattern you want to use.

Complexities of binary tree traversals

Depth first traversal of a binary tree is of order O(n).

Algo -- <b>
    PreOrderTrav():-----------------T(n)<b>
    if root is null---------------O(1)<b>
      return null-----------------O(1)<b>
    else:-------------------------O(1)<b>
      print(root)-----------------O(1)<b>
      PreOrderTrav(root.left)-----T(n/2)<b>
      PreOrderTrav(root.right)----T(n/2)<b>

If the time complexity of the algo is T(n) then it can be written as T(n) = 2*T(n/2) + O(1). If we apply back substitution we will get T(n) = O(n).

Set keyboard caret position in html textbox

Excerpted from Josh Stodola's Setting keyboard caret Position in a Textbox or TextArea with Javascript

A generic function that will allow you to insert the caret at any position of a textbox or textarea that you wish:

function setCaretPosition(elemId, caretPos) {
    var elem = document.getElementById(elemId);

    if(elem != null) {
        if(elem.createTextRange) {
            var range = elem.createTextRange();
            range.move('character', caretPos);
            range.select();
        }
        else {
            if(elem.selectionStart) {
                elem.focus();
                elem.setSelectionRange(caretPos, caretPos);
            }
            else
                elem.focus();
        }
    }
}

The first expected parameter is the ID of the element you wish to insert the keyboard caret on. If the element is unable to be found, nothing will happen (obviously). The second parameter is the caret positon index. Zero will put the keyboard caret at the beginning. If you pass a number larger than the number of characters in the elements value, it will put the keyboard caret at the end.

Tested on IE6 and up, Firefox 2, Opera 8, Netscape 9, SeaMonkey, and Safari. Unfortunately on Safari it does not work in combination with the onfocus event).

An example of using the above function to force the keyboard caret to jump to the end of all textareas on the page when they receive focus:

function addLoadEvent(func) {
    if(typeof window.onload != 'function') {
        window.onload = func;
    }
    else {
        if(func) {
            var oldLoad = window.onload;

            window.onload = function() {
                if(oldLoad)
                        oldLoad();

                func();
            }
        }
    }
}

// The setCaretPosition function belongs right here!

function setTextAreasOnFocus() {
/***
 * This function will force the keyboard caret to be positioned
 * at the end of all textareas when they receive focus.
 */
    var textAreas = document.getElementsByTagName('textarea');

    for(var i = 0; i < textAreas.length; i++) {
        textAreas[i].onfocus = function() {
            setCaretPosition(this.id, this.value.length);
        }
    }

    textAreas = null;
}

addLoadEvent(setTextAreasOnFocus);

How to get PHP $_GET array?

When you don't want to change the link (e.g. foo.php?id=1&id=2&id=3) you could probably do something like this (although there might be a better way...):

$id_arr = array();
foreach (explode("&", $_SERVER['QUERY_STRING']) as $tmp_arr_param) {
    $split_param = explode("=", $tmp_arr_param);
    if ($split_param[0] == "id") {
        $id_arr[] = urldecode($split_param[1]);
    }
}
print_r($id_arr);

Way to ng-repeat defined number of times instead of repeating over array?

 
$scope.number = 5;

<div ng-repeat="n in [] | range:$scope.number">
      <span>{{$index}}</span>
</div>

How to avoid pressing Enter with getchar() for reading a single character only?

Since you are working on a Unix derivative (Ubuntu), here is one way to do it - not recommended, but it will work (as long as you can type commands accurately):

echo "stty -g $(stty -g)" > restore-sanity
stty cbreak
./your_program

Use interrupt to stop the program when you are bored with it.

sh restore-sanity
  • The 'echo' line saves the current terminal settings as a shell script that will restore them.
  • The 'stty' line turns off most of the special processing (so Control-D has no effect, for example) and sends characters to the program as soon as they are available. It means you cannot edit your typing any more.
  • The 'sh' line reinstates your original terminal settings.

You can economize if 'stty sane' restores your settings sufficiently accurately for your purposes. The format of '-g' is not portable across versions of 'stty' (so what is generated on Solaris 10 won't work on Linux, or vice versa), but the concept works everywhere. The 'stty sane' option is not universally available, AFAIK (but is on Linux).

Remove spacing between table cells and rows

If you see table class it has border-spacing: 2px; You could override table class in your css and set its border-spacing: 0px!important in table; I did it like 

table {
      border-collapse: separate;
      white-space: normal;
      line-height: normal;
      font-weight: normal;
      font-size: medium;
      font-style: normal;
      color: -internal-quirk-inherit;
      text-align: start;
      border-spacing: 0px!important;
      font-variant: normal;   }

It saved my day.Hope it would be of help. Thanks.

How to Add Incremental Numbers to a New Column Using Pandas

Here:

df = df.reset_index()
df.columns[0] = 'New_ID'
df['New_ID'] = df.index + 880

jQuery: value.attr is not a function

The second parameter of the callback function passed to each() will contain the actual DOM element and not a jQuery wrapper object. You can call the getAttribute() method of the element:

$('#category_sorting_form_save').click(function() {
    var elements = $("#category_sorting_elements > div");
    $.each(elements, function(key, value) {
        console.info(key, ": ", value);
        console.info("cat_id: ", value.getAttribute('cat_id'));
    });
});

Or wrap the element in a jQuery object yourself:

$('#category_sorting_form_save').click(function() {
    var elements = $("#category_sorting_elements > div");
    $.each(elements, function(key, value) {
        console.info(key, ": ", value);
        console.info("cat_id: ", $(value).attr('cat_id'));
    });
});

Or simply use $(this):

$('#category_sorting_form_save').click(function() {
    var elements = $("#category_sorting_elements > div");
    $.each(elements, function() {
        console.info("cat_id: ", $(this).attr('cat_id'));
    });
});

jQuery bind to Paste Event, how to get the content of the paste

On modern browsers it's easy: just use the input event along with the inputType attribute:

$(document).on('input', 'input, textarea', function(e){
  if (e.originalEvent.inputType == 'insertFromPaste') {
    alert($(this).val());
  }
});

https://codepen.io/anon/pen/jJOWxg

Volatile Vs Atomic

The volatile keyword is used:

  • to make non atomic 64-bit operations atomic: long and double. (all other, primitive accesses are already guaranteed to be atomic!)
  • to make variable updates guaranteed to be seen by other threads + visibility effects: after writing to a volatile variable, all the variables that where visible before writing that variable become visible to another thread after reading the same volatile variable (happen-before ordering).

The java.util.concurrent.atomic.* classes are, according to the java docs:

A small toolkit of classes that support lock-free thread-safe programming on single variables. In essence, the classes in this package extend the notion of volatile values, fields, and array elements to those that also provide an atomic conditional update operation of the form:

boolean compareAndSet(expectedValue, updateValue);

The atomic classes are built around the atomic compareAndSet(...) function that maps to an atomic CPU instruction. The atomic classes introduce the happen-before ordering as the volatile variables do. (with one exception: weakCompareAndSet(...)).

From the java docs:

When a thread sees an update to an atomic variable caused by a weakCompareAndSet, it does not necessarily see updates to any other variables that occurred before the weakCompareAndSet.

To your question:

Does this mean that whosoever takes lock on it, that will be setting its value first. And in if meantime, some other thread comes up and read old value while first thread was changing its value, then doesn't new thread will read its old value?

You don't lock anything, what you are describing is a typical race condition that will happen eventually if threads access shared data without proper synchronization. As already mentioned declaring a variable volatile in this case will only ensure that other threads will see the change of the variable (the value will not be cached in a register of some cache that is only seen by one thread).

What is the difference between AtomicInteger and volatile int?

AtomicInteger provides atomic operations on an int with proper synchronization (eg. incrementAndGet(), getAndAdd(...), ...), volatile int will just ensure the visibility of the int to other threads.

IE Enable/Disable Proxy Settings via Registry

I know this is an old question, however here is a simple one-liner to switch it on or off depending on its current state:

set-itemproperty 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Internet Settings'  -name ProxyEnable -value (-not ([bool](get-itemproperty 'HKCU:\Software\Microsoft\Windows\CurrentVersion\Internet Settings'  -name ProxyEnable).proxyenable))

Does C# have an equivalent to JavaScript's encodeURIComponent()?

Uri.EscapeDataString or HttpUtility.UrlEncode is the correct way to escape a string meant to be part of a URL.

Take for example the string "Stack Overflow":

  • HttpUtility.UrlEncode("Stack Overflow") --> "Stack+Overflow"

  • Uri.EscapeUriString("Stack Overflow") --> "Stack%20Overflow"

  • Uri.EscapeDataString("Stack + Overflow") --> Also encodes "+" to "%2b" ---->Stack%20%2B%20%20Overflow

Only the last is correct when used as an actual part of the URL (as opposed to the value of one of the query string parameters)

How can I undo git reset --hard HEAD~1?

Before answering lets add some background, explaining what is this HEAD.

First of all what is HEAD?

HEAD is simply a reference to the current commit (latest) on the current branch.
There can only be a single HEAD at any given time. (excluding git worktree)

The content of HEAD is stored inside .git/HEAD and it contains the 40 bytes SHA-1 of the current commit.

detached HEAD

If you are not on the latest commit - meaning that HEAD is pointing to a prior commit in history its called detached HEAD.

enter image description here

On the command line it will look like this- SHA-1 instead of the branch name since the HEAD is not pointing to the the tip of the current branch

enter image description here

A few options on how to recover from a detached HEAD:

git checkout

git checkout <commit_id>
git checkout -b <new branch> <commit_id>
git checkout HEAD~X // x is the number of commits t go back

This will checkout new branch pointing to the desired commit.
This command will checkout to a given commit.
At this point you can create a branch and start to work from this point on.

# Checkout a given commit. 
# Doing so will result in a `detached HEAD` which mean that the `HEAD`
# is not pointing to the latest so you will need to checkout branch
# in order to be able to update the code.
git checkout <commit-id>

# create a new branch forked to the given commit
git checkout -b <branch name>

git reflog

You can always use the reflog as well.
git reflog will display any change which updated the HEAD and checking out the desired reflog entry will set the HEAD back to this commit.

Every time the HEAD is modified there will be a new entry in the reflog

git reflog
git checkout HEAD@{...}

This will get you back to your desired commit

enter image description here

git reset HEAD --hard <commit_id>

"Move" your head back to the desired commit.

# This will destroy any local modifications.
# Don't do it if you have uncommitted work you want to keep.
git reset --hard 0d1d7fc32

# Alternatively, if there's work to keep:
git stash
git reset --hard 0d1d7fc32
git stash pop
# This saves the modifications, then reapplies that patch after resetting.
# You could get merge conflicts, if you've modified things which were
# changed since the commit you reset to.
  • Note: (Since Git 2.7)
    you can also use the git rebase --no-autostash as well.

git revert <sha-1>

"Undo" the given commit or commit range.
The reset command will "undo" any changes made in the given commit.
A new commit with the undo patch will be commited while the original commit will remain in the history as well.

# add new commit with the undo of the original one.
# the <sha-1> can be any commit(s) or commit range
git revert <sha-1>

This schema illustrate which command does what.
As you can see there reset && checkout modify the HEAD.

enter image description here

Cursor adapter and sqlite example

Really simple example.

Here is a really simple, but very effective, example. Once you have the basics down you can easily build off of it.

There are two main parts to using a Cursor Adapter with SQLite:

  1. Create a proper Cursor from the Database.

  2. Create a custom Cursor Adapter that takes the Cursor data from the database and pairs it with the View you intend to represent the data with.

1. Create a proper Cursor from the Database.

In your Activity:

SQLiteOpenHelper sqLiteOpenHelper = new SQLiteOpenHelper( 
        context, DATABASE_NAME, null, DATABASE_VERSION);

SQLiteDatabase sqLiteDatabase = sqLiteOpenHelper.getReadableDatabase();

String query = "SELECT * FROM clients ORDER BY company_name ASC"; // No trailing ';'

Cursor cursor = sqLiteDatabase.rawQuery(query, null); 

ClientCursorAdapter adapter = new ClientCursorAdapter(
        this, R.layout.clients_listview_row, cursor, 0 );

this.setListAdapter(adapter);

2. Create a Custom Cursor Adapter.

Note: Extending from ResourceCursorAdapter assumes you use XML to create your views.

public class ClientCursorAdapter extends ResourceCursorAdapter {

    public ClientCursorAdapter(Context context, int layout, Cursor cursor, int flags) {
        super(context, layout, cursor, flags);
    }

    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        TextView name = (TextView) view.findViewById(R.id.name);
        name.setText(cursor.getString(cursor.getColumnIndex("name")));

        TextView phone = (TextView) view.findViewById(R.id.phone);
        phone.setText(cursor.getString(cursor.getColumnIndex("phone")));
    }
}

Getting byte array through input type = file

This is simple way to convert files to Base64 and avoid "maximum call stack size exceeded at FileReader.reader.onload" with the file has big size.

_x000D_
_x000D_ 
document.querySelector('#fileInput').addEventListener('change',   function () {_x000D_
_x000D_
    var reader = new FileReader();_x000D_
    var selectedFile = this.files[0];_x000D_
_x000D_
    reader.onload = function () {_x000D_
        var comma = this.result.indexOf(',');_x000D_
        var base64 = this.result.substr(comma + 1);_x000D_
        console.log(base64);_x000D_
    }_x000D_
    reader.readAsDataURL(selectedFile);_x000D_
}, false);
_x000D_ 
<input id="fileInput" type="file" />
_x000D_
_x000D_
_x000D_

Override body style for content in an iframe

An iframe is a 'hole' in your page that displays another web page inside of it. The contents of the iframe is not in any shape or form part of your parent page.

As others have stated, your options are:

  • give the file that is being loaded in the iframe the necessary CSS
  • if the file in the iframe is from the same domain as your parent, then you can access the DOM of the document in the iframe from the parent.

Trying to check if username already exists in MySQL database using PHP

$query = mysql_query("SELECT username FROM Users WHERE username='$username' ")

Use prepared statements, do not use mysql as it is deprecated.

// check if name is taken already
$stmt = $link->prepare("SELECT username FROM users WHERE username = :username");
$stmt->execute([
    'username' => $username
]);
$user = $stmt->fetch(PDO::FETCH_ASSOC);

if (isset($user) && !empty($user)){
    // Username already taken
}

Using COALESCE to handle NULL values in PostgreSQL

If you're using 0 and an empty string '' and null to designate undefined you've got a data problem. Just update the columns and fix your schema.

UPDATE pt.incentive_channel
SET   pt.incentive_marketing = NULL
WHERE pt.incentive_marketing = '';

UPDATE pt.incentive_channel
SET   pt.incentive_advertising = NULL
WHERE pt.incentive_marketing = '';

UPDATE pt.incentive_channel
SET   pt.incentive_channel = NULL
WHERE pt.incentive_marketing = '';

This will make joining and selecting substantially easier moving forward.

phpMyAdmin access denied for user 'root'@'localhost' (using password: NO)

found a solution, in my config file I just changed 

$cfg['Servers'][$i]['auth_type'] = 'config';

to

$cfg['Servers'][$i]['auth_type'] = 'HTTP';

Python Flask, how to set content type

As simple as this

x = "some data you want to return"
return x, 200, {'Content-Type': 'text/css; charset=utf-8'}

Hope it helps

Update: Use this method because it will work with both python 2.x and python 3.x

and secondly it also eliminates multiple header problem.

from flask import Response
r = Response(response="TEST OK", status=200, mimetype="application/xml")
r.headers["Content-Type"] = "text/xml; charset=utf-8"
return r

How to initialize an array in Java?

When you create an array of size 10 it allocated 10 slots but from 0 to 9. This for loop might help you see that a little better.

public class Array {
    int[] data = new int[10]; 
    /** Creates a new instance of an int Array */
    public Array() {
        for(int i = 0; i < data.length; i++) {
            data[i] = i*10;
        }
    }
}

Reading large text files with streams in C#

You might be better off to use memory-mapped files handling here.. The memory mapped file support will be around in .NET 4 (I think...I heard that through someone else talking about it), hence this wrapper which uses p/invokes to do the same job..

Edit: See here on the MSDN for how it works, here's the blog entry indicating how it is done in the upcoming .NET 4 when it comes out as release. The link I have given earlier on is a wrapper around the pinvoke to achieve this. You can map the entire file into memory, and view it like a sliding window when scrolling through the file.

How to use continue in jQuery each() loop?

return or return false are not the same as continue. If the loop is inside a function the remainder of the function will not execute as you would expect with a true "continue".

JSON character encoding - is UTF-8 well-supported by browsers or should I use numeric escape sequences?

The JSON spec requires UTF-8 support by decoders. As a result, all JSON decoders can handle UTF-8 just as well as they can handle the numeric escape sequences. This is also the case for Javascript interpreters, which means JSONP will handle the UTF-8 encoded JSON as well.

The ability for JSON encoders to use the numeric escape sequences instead just offers you more choice. One reason you may choose the numeric escape sequences would be if a transport mechanism in between your encoder and the intended decoder is not binary-safe.

Another reason you may want to use numeric escape sequences is to prevent certain characters appearing in the stream, such as <, & and ", which may be interpreted as HTML sequences if the JSON code is placed without escaping into HTML or a browser wrongly interprets it as HTML. This can be a defence against HTML injection or cross-site scripting (note: some characters MUST be escaped in JSON, including " and \).

Some frameworks, including PHP's implementation of JSON, always do the numeric escape sequences on the encoder side for any character outside of ASCII. This is intended for maximum compatibility with limited transport mechanisms and the like. However, this should not be interpreted as an indication that JSON decoders have a problem with UTF-8.

So, I guess you just could decide which to use like this:

  • Just use UTF-8, unless your method of storage or transport between encoder and decoder is not binary-safe.

  • Otherwise, use the numeric escape sequences.

how to redirect to home page

strRetMsg ="<script>window.location.href = '../Other/Home.htm';</script>";

Page.ClientScript.RegisterStartupScript(this.GetType(), "Script", strRetMsg,false);

Put this code in Page Load.

Django check for any exists for a query

Use count():

sc=scorm.objects.filter(Header__id=qp.id)

if sc.count() > 0:
   ...

The advantage over e.g. len() is, that the QuerySet is not yet evaluated:

count() performs a SELECT COUNT(*) behind the scenes, so you should always use count() rather than loading all of the record into Python objects and calling len() on the result.

Having this in mind, When QuerySets are evaluated can be worth reading.

If you use get(), e.g. scorm.objects.get(pk=someid), and the object does not exists, an ObjectDoesNotExist exception is raised:

from django.core.exceptions import ObjectDoesNotExist
try:
    sc = scorm.objects.get(pk=someid)
except ObjectDoesNotExist:
    print ...

Update: it's also possible to use exists():

if scorm.objects.filter(Header__id=qp.id).exists():
    ....

Returns True if the QuerySet contains any results, and False if not. This tries to perform the query in the simplest and fastest way possible, but it does execute nearly the same query as a normal QuerySet query.

Confused about UPDLOCK, HOLDLOCK

Why would UPDLOCK block selects? The Lock Compatibility Matrix clearly shows N for the S/U and U/S contention, as in No Conflict.

As for the HOLDLOCK hint the documentation states:

HOLDLOCK: Is equivalent to SERIALIZABLE. For more information, see SERIALIZABLE later in this topic.

...

SERIALIZABLE: ... The scan is performed with the same semantics as a transaction running at the SERIALIZABLE isolation level...

and the Transaction Isolation Level topic explains what SERIALIZABLE means:

No other transactions can modify data that has been read by the current transaction until the current transaction completes.

Other transactions cannot insert new rows with key values that would fall in the range of keys read by any statements in the current transaction until the current transaction completes.

Therefore the behavior you see is perfectly explained by the product documentation:

  • UPDLOCK does not block concurrent SELECT nor INSERT, but blocks any UPDATE or DELETE of the rows selected by T1
  • HOLDLOCK means SERALIZABLE and therefore allows SELECTS, but blocks UPDATE and DELETES of the rows selected by T1, as well as any INSERT in the range selected by T1 (which is the entire table, therefore any insert).
  • (UPDLOCK, HOLDLOCK): your experiment does not show what would block in addition to the case above, namely another transaction with UPDLOCK in T2:
    SELECT * FROM dbo.Test WITH (UPDLOCK) WHERE ...
  • TABLOCKX no need for explanations

The real question is what are you trying to achieve? Playing with lock hints w/o an absolute complete 110% understanding of the locking semantics is begging for trouble...

After OP edit:

I would like to select rows from a table and prevent the data in that table from being modified while I am processing it.

The you should use one of the higher transaction isolation levels. REPEATABLE READ will prevent the data you read from being modified. SERIALIZABLE will prevent the data you read from being modified and new data from being inserted. Using transaction isolation levels is the right approach, as opposed to using query hints. Kendra Little has a nice poster exlaining the isolation levels.

How to make two plots side-by-side using Python?

You can use - matplotlib.gridspec.GridSpec

Check - https://matplotlib.org/stable/api/_as_gen/matplotlib.gridspec.GridSpec.html

The below code displays a heatmap on right and an Image on left.

#Creating 1 row and 2 columns grid
gs = gridspec.GridSpec(1, 2) 
fig = plt.figure(figsize=(25,3))

#Using the 1st row and 1st column for plotting heatmap
ax=plt.subplot(gs[0,0])
ax=sns.heatmap([[1,23,5,8,5]],annot=True)

#Using the 1st row and 2nd column to show the image
ax1=plt.subplot(gs[0,1])
ax1.grid(False)
ax1.set_yticklabels([])
ax1.set_xticklabels([])

#The below lines are used to display the image on ax1
image = io.imread("https://images-na.ssl-images- amazon.com/images/I/51MvhqY1qdL._SL160_.jpg")

plt.imshow(image)
plt.show()

Output image

How to create major and minor gridlines with different linestyles in Python

A simple DIY way would be to make the grid yourself:

import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)

ax.plot([1,2,3], [2,3,4], 'ro')

for xmaj in ax.xaxis.get_majorticklocs():
  ax.axvline(x=xmaj, ls='-')
for xmin in ax.xaxis.get_minorticklocs():
  ax.axvline(x=xmin, ls='--')

for ymaj in ax.yaxis.get_majorticklocs():
  ax.axhline(y=ymaj, ls='-')
for ymin in ax.yaxis.get_minorticklocs():
  ax.axhline(y=ymin, ls='--')
plt.show()

Stopping Docker containers by image name - Ubuntu

If you want to prefer a simple AWK approach, here Is my take:

docker rm -f $(docker ps | awk '{ if($2 == "<your image name>") { print $NF}}')

$(docker ps | awk '{ if($2 == "<your image name>") { print $NF}}') - prints the docker container names based on input image

docker ps - list all containers

awk '{ if($2 == "<your-image-name>") { print $NF}}' - The second parsed column of docker ps gives the image name. Comparing it with your image name will execute print $NF which prints the container name.

docker rm -f removes the containers

For example, removing all running containers of ubuntu image, can be done simply as:

docker rm -f $(docker ps | awk '{ if($2 == "ubuntu:latest") { print $NF}}')

PS: Remember to include the image tag in AWK, since it's a equal comparator.

File Not Found when running PHP with Nginx

I had been having the same issues, And during my tests, I have faced both problems:

1º: "File not found"

and

2º: 404 Error page

And I found out that, in my case:

I had to mount volumes for my public folders both on the Nginx volumes and the PHP volumes.

If it's mounted in Nginx and is not mounted in PHP, it will give: "File not found"

Examples (Will show "File not found error"):


services:
  php-fpm:
    build:
      context: ./docker/php-fpm
  nginx:
    build:
      context: ./docker/nginx
    volumes:
        #Nginx Global Configurations
      - ./docker/nginx/nginx.conf:/etc/nginx/nginx.conf
      - ./docker/nginx/conf.d/:/etc/nginx/conf.d

        #Nginx Configurations for you Sites:

        # - Nginx Server block
      - ./sites/example.com/site.conf:/etc/nginx/sites-available/example.com.conf
        # - Copy Public Folder:
      - ./sites/example.com/root/public/:/var/www/example.com/public
    ports:
      - "80:80"
      - "443:443"
    depends_on:
      - php-fpm
    restart: always

If it's mounted in PHP and is not mounted in Nginx, it will give a 404 Page Not Found error.

Example (Will throw 404 Page Not Found Error):

version: '3'

services:
  php-fpm:
    build:
      context: ./docker/php-fpm
    volumes:
      - ./sites/example.com/root/public/:/var/www/example.com/public
  nginx:
    build:
      context: ./docker/nginx
    volumes:
        #Nginx Global Configurations
      - ./docker/nginx/nginx.conf:/etc/nginx/nginx.conf
      - ./docker/nginx/conf.d/:/etc/nginx/conf.d

        #Nginx Configurations for you Sites:

        # - Nginx Server block
      - ./sites/example.com/site.conf:/etc/nginx/sites-available/example.com.conf
    ports:
      - "80:80"
      - "443:443"
    depends_on:
      - php-fpm
    restart: always

And this would work just fine (mounting on both sides) (Assuming everything else is well configured and you're facing the same problem as me):

version: '3'

services:
  php-fpm:
    build:
      context: ./docker/php-fpm
    volumes:
      # Mount PHP for Public Folder
      - ./sites/example.com/root/public/:/var/www/example.com/public
  nginx:
    build:
      context: ./docker/nginx
    volumes:
        #Nginx Global Configurations
      - ./docker/nginx/nginx.conf:/etc/nginx/nginx.conf
      - ./docker/nginx/conf.d/:/etc/nginx/conf.d

        #Nginx Configurations for you Sites:

        # - Nginx Server block
      - ./sites/example.com/site.conf:/etc/nginx/sites-available/example.com.conf
        # - Copy Public Folder:
      - ./sites/example.com/root/public/:/var/www/example.com/public
    ports:
      - "80:80"
      - "443:443"
    depends_on:
      - php-fpm
    restart: always

Also here's a Full working example project using Nginx/Php, for serving multiple sites: https://github.com/Pablo-Camara/simple-multi-site-docker-compose-nginx-alpine-php-fpm-alpine-https-ssl-certificates

I hope this helps someone, And if anyone knows more about this please let me know, Thanks!

Change button background color using swift language

After you connect the UIButton that you want to change its background as an OUtlet to your ViewController.swift file you can use the following:

 yourUIButton.backgroundColor = UIColor.blue

Cannot push to GitHub - keeps saying need merge

I have resolve this issue at my GIT repository. No need to rebase or force commit in this case. Use below steps to resolve this -

local_barnch> git branch --set-upstream to=origin/<local_branch_name> 

local_barnch>git pull origin <local_branch_name>

local_barnch> git branch --set-upstream to=origin/master

local_barnch>git push origin <local_branch_name>

hope it will help.

How to submit a form on enter when the textarea has focus?

 
<form id="myform">
    <input type="textbox" id="field"/>
    <input type="button" value="submit">
</form>

<script>
    $(function () {
        $("#field").keyup(function (event) {
            if (event.which === 13) {
                document.myform.submit();
            }
        }
    });
</script>

Jenkins vs Travis-CI. Which one would you use for a Open Source project?

Travis-ci and Jenkins, while both are tools for continuous integration are very different.

Travis is a hosted service (free for open source) while you have to host, install and configure Jenkins.

Travis does not have jobs as in Jenkins. The commands to run to test the code are taken from a file named .travis.yml which sits along your project code. This makes it easy to have different test code per branch since each branch can have its own version of the .travis.yml file.

You can have a similar feature with Jenkins if you use one of the following plugins:

  • Travis YML Plugin - warning: does not seem to be popular, probably not feature complete in comparison to the real Travis.
  • Jervis - a modification of Jenkins to make it read create jobs from a .jervis.yml file found at the root of project code. If .jervis.yml does not exist, it will fall back to using .travis.yml file instead.

There are other hosted services you might also consider for continuous integration (non exhaustive list):

How to choose ?

You might want to stay with Jenkins because you are familiar with it or don't want to depend on 3rd party for your continuous integration system. Else I would drop Jenkins and go with one of the free hosted CI services as they save you a lot of trouble (host, install, configure, prepare jobs)

Depending on where your code repository is hosted I would make the following choices:

  • in-house ? Jenkins or gitlab-ci
  • Github.com ? Travis-CI

To setup Travis-CI on a github project, all you have to do is:

  • add a .travis.yml file at the root of your project
  • create an account at travis-ci.com and activate your project

The features you get are:

  • Travis will run your tests for every push made on your repo
  • Travis will run your tests on every pull request contributors will make

Remove plot axis values

Remove numbering on x-axis or y-axis:

plot(1:10, xaxt='n')
plot(1:10, yaxt='n')

If you want to remove the labels as well:

plot(1:10, xaxt='n', ann=FALSE)
plot(1:10, yaxt='n', ann=FALSE)

Responsively change div size keeping aspect ratio

You can do this using pure CSS; no JavaScript needed. This utilizes the (somewhat counterintuitive) fact that padding-top percentages are relative to the containing block's width. Here's an example:

_x000D_
_x000D_ 
.wrapper {_x000D_
  width: 50%;_x000D_
  /* whatever width you want */_x000D_
  display: inline-block;_x000D_
  position: relative;_x000D_
}_x000D_
.wrapper:after {_x000D_
  padding-top: 56.25%;_x000D_
  /* 16:9 ratio */_x000D_
  display: block;_x000D_
  content: '';_x000D_
}_x000D_
.main {_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  bottom: 0;_x000D_
  right: 0;_x000D_
  left: 0;_x000D_
  /* fill parent */_x000D_
  background-color: deepskyblue;_x000D_
  /* let's see it! */_x000D_
  color: white;_x000D_
}
_x000D_ 
<div class="wrapper">_x000D_
  <div class="main">_x000D_
    This is your div with the specified aspect ratio._x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Eclipse Problems View not showing Errors anymore

I have the same issue with Eclipse Helios and the m2eclipse plugin. They just can't seem to get this thing to work with WTP or WPT or whatever the blasted acronym is.

If I do a clean on the project and watch the Maven console then I can see the compilation issues in the console but eclipse won't touch it. It seems eclipse or WTP/WPT and m2eclipse are busy playing slap hands.

How to force NSLocalizedString to use a specific language

What do you think about this solution for Swift 3?

extension String {

    func localized(forLanguage language: String = Locale.preferredLanguages.first!.components(separatedBy: "-").first!) -> String {

        guard let path = Bundle.main.path(forResource: language == "en" ? "Base" : language, ofType: "lproj") else {

            let basePath = Bundle.main.path(forResource: "Base", ofType: "lproj")!

            return Bundle(path: basePath)!.localizedString(forKey: self, value: "", table: nil)
        }

        return Bundle(path: path)!.localizedString(forKey: self, value: "", table: nil)
    }
}

Simple usage:

"report".localized(forLanguage: "pl") //forced language
"report".localized() //default language selected by user in settings, in case when your app doesnt support selected lanaguage, the default one is selected, here is an english.

How to set the default value for radio buttons in AngularJS?

 
<div ng-app="" ng-controller="myCntrl">    
        <input type="radio" ng-model="people" value="1"/><label>1</label>
        <input type="radio" ng-model="people" value="2"/><label>2</label>
        <input type="radio" ng-model="people" value="3"/><label>3</label>
</div>
<script>
    function myCntrl($scope){
        $scope.people=1;
    }
</script>

How to scale a UIImageView proportionally?

I think you can do something like

image.center = [[imageView window] center];

How to run iPhone emulator WITHOUT starting Xcode?

From Terminal just run this command:

ios-sim  start

Or,add this to your ~/.profile to save yourself a few keystrokes:

alias ios="ios-sim  start"

Not sure which version of Max OS X and Xcode this command became available. I'm running 10.10.3 and 6.3 respectively.

macro - open all files in a folder

You have to add this line just before loop

    MyFile = Dir
Loop

How to bring view in front of everything?

Try FrameLayout, it gives you the possibility to put views one above another. You can create two LinearLayouts: one with the background views, and one with foreground views, and combine them using the FrameLayout. Hope this helps.

how to break the _.each function in underscore.js

It's also good to note that an each loop cannot be broken out of — to break, use _.find instead.

http://underscorejs.org/#each

C# Pass Lambda Expression as Method Parameter

You should use a delegate type and specify that as your command parameter. You could use one of the built in delegate types - Action and Func.

In your case, it looks like your delegate takes two parameters, and returns a result, so you could use Func:

List<IJob> GetJobs(Func<FullTimeJob, Student, FullTimeJob> projection)

You could then call your GetJobs method passing in a delegate instance. This could be a method which matches that signature, an anonymous delegate, or a lambda expression.

P.S. You should use PascalCase for method names - GetJobs, not getJobs.

How do I pass a variable by reference?

Effbot (aka Fredrik Lundh) has described Python's variable passing style as call-by-object: http://effbot.org/zone/call-by-object.htm

Objects are allocated on the heap and pointers to them can be passed around anywhere.

  • When you make an assignment such as x = 1000, a dictionary entry is created that maps the string "x" in the current namespace to a pointer to the integer object containing one thousand.

  • When you update "x" with x = 2000, a new integer object is created and the dictionary is updated to point at the new object. The old one thousand object is unchanged (and may or may not be alive depending on whether anything else refers to the object).

  • When you do a new assignment such as y = x, a new dictionary entry "y" is created that points to the same object as the entry for "x".

  • Objects like strings and integers are immutable. This simply means that there are no methods that can change the object after it has been created. For example, once the integer object one-thousand is created, it will never change. Math is done by creating new integer objects.

  • Objects like lists are mutable. This means that the contents of the object can be changed by anything pointing to the object. For example, x = []; y = x; x.append(10); print y will print [10]. The empty list was created. Both "x" and "y" point to the same list. The append method mutates (updates) the list object (like adding a record to a database) and the result is visible to both "x" and "y" (just as a database update would be visible to every connection to that database).

Hope that clarifies the issue for you.

Creating a selector from a method name with parameters

Beyond what's been said already about selectors, you may want to look at the NSInvocation class.

An NSInvocation is an Objective-C message rendered static, that is, it is an action turned into an object. NSInvocation objects are used to store and forward messages between objects and between applications, primarily by NSTimer objects and the distributed objects system.

An NSInvocation object contains all the elements of an Objective-C message: a target, a selector, arguments, and the return value. Each of these elements can be set directly, and the return value is set automatically when the NSInvocation object is dispatched.

Keep in mind that while it's useful in certain situations, you don't use NSInvocation in a normal day of coding. If you're just trying to get two objects to talk to each other, consider defining an informal or formal delegate protocol, or passing a selector and target object as has already been mentioned.

Installation failed with message Invalid File

I found the solution go to

settings>build,execute,deployment>instant run>Enable instant run to hot swap code /resource change on deploy(unchecked this option)

`

How to squash commits in git after they have been pushed?

A lot of problems can be avoided by only creating a branch to work on & not working on master:

git checkout -b mybranch

The following works for remote commits already pushed & a mixture of remote pushed commits / local only commits:

# example merging 4 commits

git checkout mybranch
git rebase -i mybranch~4 mybranch

# at the interactive screen
# choose fixup for commit: 2 / 3 / 4

git push -u origin +mybranch

I also have some pull request notes which may be helpful.

VBScript to send email without running Outlook

Yes. Blat or any other self contained SMTP mailer. Blat is a fairly full featured SMTP client that runs from command line

Blat is here

Jquery Date picker Default Date

i suspect that your default date format is different than the scripts default settigns. test your script with the 'dateformat' option

$( "#datepicker" ).datepicker({ 
    dateFormat: 'dd-mm-yy'
});

instead of dd-mm-yy, your desired format

Invalid length parameter passed to the LEFT or SUBSTRING function

That would only happen if PostCode is missing a space. You could add conditionality such that all of PostCode is retrieved should a space not be found as follows

select SUBSTRING(PostCode, 1 ,
case when  CHARINDEX(' ', PostCode ) = 0 then LEN(PostCode) 
else CHARINDEX(' ', PostCode) -1 end)

How do I put an already-running process under nohup?

These are good answers above, I just wanted to add a clarification:

You can't disown a pid or process, you disown a job, and that is an important distinction.

A job is something that is a notion of a process that is attached to a shell, therefore you have to throw the job into the background (not suspend it) and then disown it.

Issue:

%  jobs
[1]  running java 
[2]  suspended vi
%  disown %1

See http://www.quantprinciple.com/invest/index.php/docs/tipsandtricks/unix/jobcontrol/ for a more detailed discussion of Unix Job Control.

Get response from PHP file using AJAX

 
<script type="text/javascript">
        function returnwasset(){
            alert('return sent');
            $.ajax({
                type: "POST",
                url: "process.php",
                data: somedata;
                dataType:'text'; //or HTML, JSON, etc.
                success: function(response){
                    alert(response);
                    //echo what the server sent back...
                }
            });
        }
    </script>

Open a local HTML file using window.open in Chrome

This worked for me fine:

File 1:

    <html>
    <head></head>
    <body>
        <a href="#" onclick="window.open('file:///D:/Examples/file2.html'); return false">CLICK ME</a>
    </body>
    <footer></footer>
    </html>

File 2:

    <html>
        ...
    </html>

This method works regardless of whether or not the 2 files are in the same directory, BUT both files must be local.

For obvious security reasons, if File 1 is located on a remote server you absolutely cannot open a file on some client's host computer and trying to do so will open a blank target.

DataRow: Select cell value by a given column name

You can get the column value in VB.net

Dim row As DataRow = fooTable.Rows(0)
Dim temp = Convert.ToString(row("ColumnName"))

And in C# you can use Jimmy's Answer, just be careful while converting it to ToString(). It can throw null exception if the data is null instead Use Convert.ToString(your_expression) to avoid null exception reference

Opening Android Settings programmatically

To achieve this just use an Intent using the constant ACTION_SETTINGS, specifically defined to show the System Settings:

startActivity(new Intent(Settings.ACTION_SETTINGS));

startActivityForResult() is optional, only if you want to return some data when the settings activity is closed.

startActivityForResult(new Intent(Settings.ACTION_SETTINGS), 0);

here you can find a list of contants to show specific settings or details of an aplication.

Eclipse change project files location

Much more simple: Right click -> Refactor -> Move.

Neither user 10102 nor current process has android.permission.READ_PHONE_STATE

I was experiencing this problem on Samsung devices (fine on others). like zyamys suggested in his/her comment, I added the manifest.permission line but in addition to rather than instead of the original line, so:

<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.Manifest.permission.READ_PHONE_STATE" />

I'm targeting API 22, so don't need to explicitly ask for permissions.

Performing a Stress Test on Web Application?

I've used The Grinder. It's open source, pretty easy to use, and very configurable. It is Java based and uses Jython for the scripts. We ran it against a .NET web application, so don't think it's a Java only tool (by their nature, any web stress tool should not be tied to the platform it uses).

We did some neat stuff with it... we were a web based telecom application, so one cool use I set up was to mimick dialing a number through our web application, then used an auto answer tool we had (which was basically a tutorial app from Microsoft to connect to their RTC LCS server... which is what Microsoft Office Communicator connects to on a local network... then modified to just pick up calls automatically). This then allowed us to use this instead of an expensive telephony tool called The Hammer (or something like that).

Anyways, we also used the tool to see how our application held up under high load, and it was very effective in finding bottlenecks. The tool has built in reporting to show how long requests are taking, but we never used it. The logs can also store all the responses and whatnot, or custom logging.

I highly recommend this tool, very useful for the price... but expect to do some custom setup with it (it has a built in proxy to record a script, but it may need customization for capturing something like sessions... I know I had to customize it to utilize a unique session per thread).

Why Local Users and Groups is missing in Computer Management on Windows 10 Home?

Windows 10 Home Edition does not have Local Users and Groups option so that is the reason you aren't able to see that in Computer Management.

You can use User Accounts by pressing Window+R, typing netplwiz and pressing OK as described here.

Loading custom functions in PowerShell

You have to dot source them:

. .\build_funtions.ps1
. .\build_builddefs.ps1

Note the extra .

This heyscriptingguy article should be of help - How to Reuse Windows PowerShell Functions in Scripts

How to maximize a plt.show() window using Python

The one solution that worked on Win 10 flawlessly.

import matplotlib.pyplot as plt

plt.plot(x_data, y_data)

mng = plt.get_current_fig_manager()
mng.window.state("zoomed")
plt.show()

What does it mean to "call" a function in Python?

When you "call" a function you are basically just telling the program to execute that function. So if you had a function that added two numbers such as:

def add(a,b):
    return a + b

you would call the function like this:

add(3,5)

which would return 8. You can put any two numbers in the parentheses in this case. You can also call a function like this:

answer = add(4,7)

Which would set the variable answer equal to 11 in this case.

What is the difference between Tomcat, JBoss and Glassfish?

jboss and glassfish include a servlet container(like tomcat), however the two application servers (jboss and glassfish) also provide a bean container (and a few other things aswell I imagine)

How to execute cmd commands via Java

If you want to run several commands in the cmd shell then you can construct a single command like this:

  rt.exec("cmd /c start cmd.exe /K \"cd c:/ && dir\"");

This page explains more.

Find files in a folder using Java

Consider Apache Commons IO, it has a class called FileUtils that has a listFiles method that might be very useful in your case.

How to know the size of the string in bytes?

 
System.Text.ASCIIEncoding.Unicode.GetByteCount(yourString);

Or

System.Text.ASCIIEncoding.ASCII.GetByteCount(yourString);

Exception of type 'System.OutOfMemoryException' was thrown. Why?

It runs successfully the first time, but if I run it again, I keep getting a System.OutOfMemoryException. What are some reasons this could be happening?

Regardless of what the others have said, the error has nothing to do with forgetting to dispose your DBCommand or DBConnection, and you will not fix your error by disposing of either of them.

The error has everything to do with your dataset which contains nearly 600,000 rows of data. Apparently your dataset consumes more than 50% of the available memory on your machine. Clearly, you'll run out of memory when you return another dataset of the same size before the first one has been garbage collected. Simple as that.

You can remedy this problem in a few ways:

  • Consider returning fewer records. I personally can't imagine a time when returning 600K records has ever been useful to a user. To minimize the records returned, try:

    • Limiting your query to the first 1000 records. If there are more than 1000 results returned from the query, inform the user to narrow their search results.

    • If your users really insist on seeing that much data at once, try paging the data. Remember: Google never shows you all 22 bajillion results of a search at once, it shows you 20 or so records at a time. Google probably doesn't hold all 22 bajillion results in memory at once, it probably finds its more memory efficient to requery its database to generate a new page.

  • If you just need to iterate through the data and you don't need random access, try returning a datareader instead. A datareader only loads one record into memory at a time.

If none of those are an option, then you need to force .NET to free up the memory used by the dataset before calling your method using one of these methods:

  • Remove all references to your old dataset. Anything holding on to a refenence of your dataset will prevent it from being reclaimed by memory.

  • If you can't null all the references to your dataset, clear all of the rows from the dataset and any objects bound to those rows instead. This removes references to the datarows and allows them to be eaten by the garbage collector.

I don't believe you'll need to call GC.Collect() to force a gen cycle. Not only is it generally a bad idea to call GC.Collect(), because sufficient memory pressure will cause .NET invoke the garbage collector on its own.

Note: calling Dispose on your dataset does not free any memory, nor does it invoke the garbage collector, nor does it remove a reference to your dataset. Dispose is used to clean up unmanaged resources, but the DataSet does not have any unmanaged resources. It only implements IDispoable because it inherents from MarshalByValueComponent, so the Dispose method on the dataset is pretty much useless.

Is there a way to suppress JSHint warning for one given line?

The "evil" answer did not work for me. Instead, I used what was recommended on the JSHints docs page. If you know the warning that is thrown, you can turn it off for a block of code. For example, I am using some third party code that does not use camel case functions, yet my JSHint rules require it, which led to a warning. To silence it, I wrote:

/*jshint -W106 */
save_state(id);
/*jshint +W106 */

How do I do a case-insensitive string comparison?

How about converting to lowercase first? you can use string.lower().

Compiling problems: cannot find crt1.o

./configure --disable-multilib

works for it

Using LIKE operator with stored procedure parameters

Your datatype for @location nchar(20) should be @location nvarchar(20), since nChar has a fixed length (filled with Spaces).
If Location is nchar too you will have to convert it: 

 ... Cast(Location as nVarchar(200)) like '%'+@location+'%' ...

To enable nullable parameters with and AND condition just use IsNull or Coalesce for comparison, which is not needed in your example using OR.

e.g. if you would like to compare for Location AND Date and Time. 

@location nchar(20),
@time time,
@date date
as
select DonationsTruck.VechileId, Phone, Location, [Date], [Time]
from Vechile, DonationsTruck
where Vechile.VechileId = DonationsTruck.VechileId
and (((Location like '%'+IsNull(@location,Location)+'%')) and [Date]=IsNUll(@date,date) and [Time] = IsNull(@time,Time))

Count occurrences of a char in a string using Bash

I would use the following awk command:

string="text,text,text,text"
char=","
awk -F"${char}" '{print NF-1}' <<< "${string}"

I'm splitting the string by $char and print the number of resulting fields minus 1.

If your shell does not support the <<< operator, use echo:

echo "${string}" | awk -F"${char}" '{print NF-1}'

Check if current directory is a Git repository

Not sure if there is a publicly accessible/documented way to do this (there are some internal git functions which you can use/abuse in the git source itself)

You could do something like;

if ! git ls-files >& /dev/null; then
  echo "not in git"
fi

jQuery .live() vs .on() method for adding a click event after loading dynamic html

Try this:

$('#parent').on('click', '#child', function() {
    // Code
});

From the $.on() documentation:

Event handlers are bound only to the currently selected elements; they must exist on the page at the time your code makes the call to .on().

Your #child element doesn't exist when you call $.on() on it, so the event isn't bound (unlike $.live()). #parent, however, does exist, so binding the event to that is fine.

The second argument in my code above acts as a 'filter' to only trigger if the event bubbled up to #parent from #child.

Android adding simple animations while setvisibility(view.Gone)

Find the below code to make visible the view in Circuler reveal, if you send true, it'll get Invisible/Gone. If you send false, it'll get visible. anyView is the view you're going to visible/hide, it could be any view (Layouts, Buttons etc)

 private fun toggle(flag: Boolean, anyView: View) {
    if (flag) {
        val cx = anyView.width / 2
        val cy = anyView.height / 2
        val initialRadius = Math.hypot(cx.toDouble(), cy.toDouble()).toFloat()
        val anim = ViewAnimationUtils.createCircularReveal(anyView, cx, cy, initialRadius, 0f)
        anim.addListener(object : AnimatorListenerAdapter() {
            override fun onAnimationEnd(animation: Animator) {
                super.onAnimationEnd(animation)
                anyView.visibility = View.INVISIBLE
            }
        })
        anim.start()
    } else {
        val cx = anyView.width / 2
        val cy = anyView.height / 2
        val finalRadius = Math.hypot(cx.toDouble(), cy.toDouble()).toFloat()
        val anim = ViewAnimationUtils.createCircularReveal(anyView, cx, cy, 0f, finalRadius)
        anyView.visibility = View.VISIBLE
        anim.start()
    }
}

Set element width or height in Standards Mode

The style property lets you specify values for CSS properties.

The CSS width property takes a length as its value.

Lengths require units. In quirks mode, browsers tend to assume pixels if provided with an integer instead of a length. Specify units.

e1.style.width = "400px";

What is the difference between screenX/Y, clientX/Y and pageX/Y?

The difference between those will depend largely on what browser you are currently referring to. Each one implements these properties differently, or not at all. Quirksmode has great documentation regarding browser differences in regards to W3C standards like the DOM and JavaScript Events.

How to create a session using JavaScript?

Use HTML5 Local Storage. you can store and use the data anytime you please.

<script>
    // Store
    localStorage.setItem("lastname", "Smith");

    // Retrieve
    var data = localStorage.getItem("lastname");

</script>

Tuples( or arrays ) as Dictionary keys in C#

Between tuple and nested dictionaries based approaches, it's almost always better to go for tuple based.

From maintainability point of view,

  • its much easier to implement a functionality that looks like:

    var myDict = new Dictionary<Tuple<TypeA, TypeB, TypeC>, string>();

    than

    var myDict = new Dictionary<TypeA, Dictionary<TypeB, Dictionary<TypeC, string>>>();

    from the callee side. In the second case each addition, lookup, removal etc require action on more than one dictionary.

  • Furthermore, if your composite key require one more (or less) field in future, you will need to change code a significant lot in the second case (nested dictionary) since you have to add further nested dictionaries and subsequent checks.

From performance perspective, the best conclusion you can reach is by measuring it yourself. But there are a few theoretical limitations which you can consider beforehand:

  • In the nested dictionary case, having an additional dictionary for every keys (outer and inner) will have some memory overhead (more than what creating a tuple would have).

  • In the nested dictionary case, every basic action like addition, updation, lookup, removal etc need to be carried out in two dictionaries. Now there is a case where nested dictionary approach can be faster, i.e., when the data being looked up is absent, since the intermediate dictionaries can bypass the full hash code computation & comparison, but then again it should be timed to be sure. In presence of data, it should be slower since lookups should be performed twice (or thrice depending on nesting).

  • Regarding tuple approach, .NET tuples are not the most performant when they're meant to be used as keys in sets since its Equals and GetHashCode implementation causes boxing for value types.

I would go with tuple based dictionary, but if I want more performance, I would use my own tuple with better implementation.

On a side note, few cosmetics can make the dictionary cool:

  1. Indexer style calls can be a lot cleaner and intuitive. For eg,

    string foo = dict[a, b, c]; //lookup
dict[a, b, c] = ""; //update/insertion

    So expose necessary indexers in your dictionary class which internally handles the insertions and lookups.

  2. Also, implement a suitable IEnumerable interface and provide an Add(TypeA, TypeB, TypeC, string) method which would give you collection initializer syntax, like:

    new MultiKeyDictionary<TypeA, TypeB, TypeC, string> 
{ 
    { a, b, c, null }, 
    ...
};

rbind error: "names do not match previous names"

check all the variables names in both of the combined files. Name of variables of both files to be combines should be exact same or else it will produce the above mentioned errors. I was facing the same problem as well, and after making all names same in both the file, rbind works accurately.

Thanks

JOptionPane Yes or No window

"if(true)" will always be true and it will never make it to the else. If you want it to work correctly you have to do this:

int reply = JOptionPane.showConfirmDialog(null, message, title, JOptionPane.YES_NO_OPTION);
if (reply == JOptionPane.YES_OPTION) {
    JOptionPane.showMessageDialog(null, "HELLO");
} else {
    JOptionPane.showMessageDialog(null, "GOODBYE");
    System.exit(0);
}

Failure [INSTALL_FAILED_ALREADY_EXISTS] when I tried to update my application

If u still facing problem then try to uninstall application using command prompt. just add command adb uninstall com.example.yourpackagename then try to re-install again.It works!

javax.naming.NoInitialContextException - Java

We need to specify the INITIAL_CONTEXT_FACTORY, PROVIDER_URL, USERNAME, PASSWORD etc. of JNDI to create an InitialContext.

In a standalone application, you can specify that as below

Hashtable env = new Hashtable();
env.put(Context.INITIAL_CONTEXT_FACTORY, 
    "com.sun.jndi.ldap.LdapCtxFactory");
env.put(Context.PROVIDER_URL, "ldap://ldap.wiz.com:389");
env.put(Context.SECURITY_PRINCIPAL, "joeuser");
env.put(Context.SECURITY_CREDENTIALS, "joepassword");

Context ctx = new InitialContext(env);

But if you are running your code in a Java EE container, these values will be fetched by the container and used to create an InitialContext as below

System.getProperty(Context.PROVIDER_URL);

and

these values will be set while starting the container as JVM arguments. So if you are running the code in a container, the following will work

InitialContext ctx = new InitialContext();

JPG vs. JPEG image formats

There's no difference between the file extensions, and they are used interchangeably. I guess the 3-letter version stems from the DOS era...

However, there are different "flavors" of JPEG files. Most notably the JFIF standard and the EXIF standard. Most often these just use .jpg or .jpeg as file extensions, JFIF sometimes uses .jif or .jfif.

What is the volatile keyword useful for?

A variable declared with volatile keyword, has two main qualities which make it special.

  1. If we have a volatile variable, it cannot be cached into the computer's(microprocessor) cache memory by any thread. Access always happened from main memory.

  2. If there is a write operation going on a volatile variable, and suddenly a read operation is requested, it is guaranteed that the write operation will be finished prior to the read operation.

Two above qualities deduce that

  • All the threads reading a volatile variable will definitely read the latest value. Because no cached value can pollute it. And also the read request will be granted only after the completion of the current write operation.

And on the other hand,

  • If we further investigate the #2 that I have mentioned, we can see that volatile keyword is an ideal way to maintain a shared variable which has 'n' number of reader threads and only one writer thread to access it. Once we add the volatile keyword, it is done. No any other overhead about thread safety.

Conversly,

We can't make use of volatile keyword solely, to satisfy a shared variable which has more than one writer thread accessing it.

Call a child class method from a parent class object

Many of the answers here are suggesting implementing variant types using "Classical Object-Oriented Decomposition". That is, anything which might be needed on one of the variants has to be declared at the base of the hierarchy. I submit that this is a type-safe, but often very bad, approach. You either end up exposing all internal properties of all the different variants (most of which are "invalid" for each particular variant) or you end up cluttering the API of the hierarchy with tons of procedural methods (which means you have to recompile every time a new procedure is dreamed up).

I hesitate to do this, but here is a shameless plug for a blog post I wrote that outlines about 8 ways to do variant types in Java. They all suck, because Java sucks at variant types. So far the only JVM language that gets it right is Scala.

http://jazzjuice.blogspot.com/2010/10/6-things-i-hate-about-java-or-scala-is.html

The Scala creators actually wrote a paper about three of the eight ways. If I can track it down, I'll update this answer with a link.

UPDATE: found it here.

Plot bar graph from Pandas DataFrame

To plot just a selection of your columns you can select the columns of interest by passing a list to the subscript operator:

ax = df[['V1','V2']].plot(kind='bar', title ="V comp", figsize=(15, 10), legend=True, fontsize=12)

What you tried was df['V1','V2'] this will raise a KeyError as correctly no column exists with that label, although it looks funny at first you have to consider that your are passing a list hence the double square brackets [[]].

import matplotlib.pyplot as plt
ax = df[['V1','V2']].plot(kind='bar', title ="V comp", figsize=(15, 10), legend=True, fontsize=12)
ax.set_xlabel("Hour", fontsize=12)
ax.set_ylabel("V", fontsize=12)
plt.show()

enter image description here

How to check empty object in angular 2 template using *ngIf

Above answers are okay. But I have found a really nice option to use following in the view:

{{previous_info?.title}}

probably duplicated question Angular2 - error if don't check if {{object.field}} exists

Android get Current UTC time

see my answer here:

How can I get the current date and time in UTC or GMT in Java?

I've fully tested it by changing the timezones on the emulator

Decompile Python 2.7 .pyc

Here is a great tool to decompile pyc files.

It was coded by me and supports python 1.0 - 3.3

Its based on uncompyle2 and decompyle++

http://sourceforge.net/projects/easypythondecompiler/

How to get a view table query (code) in SQL Server 2008 Management Studio

Use sp_helptext before the view_name. Example:

sp_helptext Example_1

Hence you will get the query:

CREATE VIEW dbo.Example_1
AS
SELECT       a, b, c
FROM         dbo.table_name JOIN blah blah blah
WHERE        blah blah blah

sp_helptext will give stored procedures.

How do I combine a background-image and CSS3 gradient on the same element?

I wanted to make span button with background image, background gradient combination.

http://enjoycss.com/ helped to do my work task. Only I have to remove some auto generated additional CSS. But it's really nice site build your scratch work.

#nav a.link-style span {
    background: url("../images/order-now-mobile.png"), -webkit-linear-gradient(0deg, rgba(190,20,27,1) 0, rgba(224,97,102,1) 51%, rgba(226,0,0,1) 100%);
    background: url("../images/order-now-mobile.png"), -moz-linear-gradient(90deg, rgba(190,20,27,1) 0, rgba(224,97,102,1) 51%, rgba(226,0,0,1) 100%);
    background: url("../images/order-now-mobile.png"), linear-gradient(90deg, rgba(170,31,0,1) 0, rgba(214,18,26,1) 51%, rgba(170,31,0,1) 100%);
    background-repeat: no-repeat;
    background-position: 50% 50%;
    border-radius: 8px;
    border: 3px solid #b30a11;
}

CR LF notepad++ removal

enter image description hereGoto View -> Show Symbol Select as per screen-shot, you will get correct

How to get HTML 5 input type="date" working in Firefox and/or IE 10

The type="date" is not an actual specification at this point. It is a concept Google came up with and is in their whatwg specifications (not official) and is only partially supported by Chrome.

http://caniuse.com/#search=date

I would not rely on this input type at this point. It would be nice to have, but I do not foresee this one actually making it. The #1 reason is it puts too much burden on the browser to determine the best UI for a somewhat complicated input. Think about it from a responsive perspective, how would any of the vendors know what will work best with your UI say at 400 pixels, 800 pixels and 1200 pixels wide?

ReactJS map through Object

I use the below Object.entries to easily output the key and the value:

{Object.entries(someObject).map(([key, val], i) => (
    <p key={i}>
        {key}: {val}
    </p>
))}

How do you extract a column from a multi-dimensional array?

check it out!

a = [[1, 2], [2, 3], [3, 4]]
a2 = zip(*a)
a2[0]

it is the same thing as above except somehow it is neater the zip does the work but requires single arrays as arguments, the *a syntax unpacks the multidimensional array into single array arguments

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

Updating Proguard to latest version solved it for me.

  • My proguard path was C:\Program Files (x86)\Android\android-sdk\tools\proguard\
  • I downloaded the new version from here
  • and replaced both bin and lib folders

THANK GOD!

Warning: mysqli_query() expects parameter 1 to be mysqli, null given in

The getPosts() function seems to be expecting $con to be global, but you're not declaring it as such.

A lot of programmers regard bald global variables as a "code smell". The alternative at the other end of the scale is to always pass around the connection resource. Partway between the two is a singleton call that always returns the same resource handle.

IndentationError expected an indented block

If you are using a mac and sublime text 3, this is what you do.

Go to your /Packages/User/ and create a file called Python.sublime-settings.

Typically /Packages/User is inside your ~/Library/Application Support/Sublime Text 3/Packages/User/Python.sublime-settings if you are using mac os x.

Then you put this in the Python.sublime-settings.

{
    "tab_size": 4,
    "translate_tabs_to_spaces": false
}

Credit goes to Mark Byer's answer, sublime text 3 docs and python style guide.

This answer is mostly for readers who had the same issue and stumble upon this and are using sublime text 3 on Mac OS X.

Counting lines, words, and characters within a text file using Python

 
fname = "feed.txt"
feed = open(fname, 'r')

num_lines = len(feed.splitlines())
num_words = 0
num_chars = 0

for line in lines:
    num_words += len(line.split())

Why does HTML think “chucknorris” is a color?

I now this this is not an image made by me, but this image can help a lot... enter image description here

So, here is an little app that I created so you can play with the values

_x000D_
_x000D_ 
function parseColor(input) {
  input = input.trim();
  if (input.length > 128) {
    input = input.slice(0, 128);
  }
  if (input.charAt(0) === "#") {
    input = input.slice(1);
  }
  input = input.replace(/[^0-9A-Fa-f]/g, "0");
  while (input.length === 0 || input.length % 3 > 0) {
    input += "0";
  }
  var r = input.slice(0, input.length / 3);
  var g = input.slice(input.length / 3, input.length * 2 / 3);
  var b = input.slice(input.length * 2 / 3);
  if (r.length > 8) {
    r = r.slice(-8);
    g = g.slice(-8);
    b = b.slice(-8);
  }
  while (r.length > 2 && r.charAt(0) === "0" && g.charAt(0) === "0" && b.charAt(0) === "0") {
    r = r.slice(1);
    g = g.slice(1);
    b = b.slice(1);
  }
  if (r.length > 2) {
    r = r.slice(0, 2);
    g = g.slice(0, 2);
    b = b.slice(0, 2);
  }
  return "#" + r.padStart(2, "0") + g.padStart(2, "0") + b.padStart(2, "0");
}

$(function() {
  $("#input").on("change", function() {
    var input = $(this).val();
    var color = parseColor(input);
    var $cells = $("#result tbody td");
    $cells.eq(0).attr("bgcolor", input);
    $cells.eq(1).attr("bgcolor", color);

    var color1 = $cells.eq(0).css("background-color");
    var color2 = $cells.eq(1).css("background-color");
    $cells.eq(2).empty().append("background-color: " + input, "<br>", "getComputedStyle: " + color1);
    $cells.eq(3).empty().append("background-color: " + color, "<br>", "getComputedStyle: " + color2);
  });
});
_x000D_ 
* { font: monospace; }
input { width: 100hv; }
table { table-layout: fixed; width: 100%; }
input {border: 1px solid black;border-radius: 5px;outline:none;padding: 10px; }
_x000D_ 
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>

<p><input id="input" placeholder="Enter color e.g. demofothedayischur000! or ffffssssrrrddswww!"></p><details>
<summary>Color examples (drag-and-drop)</summary>
Try this colors:<br>
Batato<br>
Muatre!<br>
fsdyelow"<br>
000meandthis<br>
!!!!!<br>
entrcolor<br>
yellowofthe!<br>
!!!me!!!you!!!aregre!:;H<br>
!"#$%&/()=<br>
/()=??»»<br>
thsdem<br></details>
<details>
<summary>
Or.... Want a big example?
</summary>
Here it goes:<br>
Batato Muatre! dtexbtfe dodx42 f 1dzxwq lorem ip os dh4huryx nyxze eimqdmuezo fsdyelow" 000meandthis !!!!! entrcolor yellowofthe! !!!me!!!you!!!aregre!:;H !"#$%&/()= /()=??»» thsdem
</details>
<table id="result">
  <thead>
    <tr>
      <th>Left Color</th>
      <th>Right Color</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>&nbsp;</td>
      <td>&nbsp;</td>
    </tr>
    <tr>
      <td>&nbsp;</td>
      <td>&nbsp;</td>
    </tr>
  </tbody>
</table>
_x000D_
_x000D_
_x000D_

Change color inside strings.xml

For those who want to put color in String.xml directly and don't want to use color...

example

<string name="status_stop"><font fgcolor='#FF8E8E93'>Stopped</font></string> <!--gray-->
<string name="status_running"><font fgcolor='#FF4CD964'>Running</font></string> <!--green-->
<string name="status_error"><font fgcolor='#FFFF3B30'>Error</font></string> <!--red-->

as you see there is gray, red, and green, there is 8 characters, first two for transparency and other for color.

Example

This a description of color and transparency
#   FF               FF3B30    
    Opacity          Color

Note: Put color in text in the same string.xml will not work in Android 6.0 and above

Table of opacity

100% — FF
99% — FC
98% — FA
97% — F7
96% — F5
95% — F2
94% — F0
93% — ED
92% — EB
91% — E8
90% — E6
89% — E3
88% — E0
87% — DE
86% — DB
85% — D9
84% — D6
83% — D4
82% — D1
81% — CF
80% — CC
79% — C9
78% — C7
77% — C4
76% — C2
75% — BF
74% — BD
73% — BA
72% — B8
71% — B5
70% — B3
69% — B0
68% — AD
67% — AB
66% — A8
65% — A6
64% — A3
63% — A1
62% — 9E
61% — 9C
60% — 99
59% — 96
58% — 94
57% — 91
56% — 8F
55% — 8C
54% — 8A
53% — 87
52% — 85
51% — 82
50% — 80
49% — 7D
48% — 7A
47% — 78
46% — 75
45% — 73
44% — 70
43% — 6E
42% — 6B
41% — 69
40% — 66
39% — 63
38% — 61
37% — 5E
36% — 5C
35% — 59
34% — 57
33% — 54
32% — 52
31% — 4F
30% — 4D
29% — 4A
28% — 47
27% — 45
26% — 42
25% — 40
24% — 3D
23% — 3B
22% — 38
21% — 36
20% — 33
19% — 30
18% — 2E
17% — 2B
16% — 29
15% — 26
14% — 24
13% — 21
12% — 1F
11% — 1C
10% — 1A
9% — 17
8% — 14
7% — 12
6% — 0F
5% — 0D
4% — 0A
3% — 08
2% — 05
1% — 03
0% — 00

Reference: Understanding colors in Android (6 characters)

Update: 10/OCT/2016

This function is compatible with all version of android, I didn't test in android 7.0. Use this function to get color and set in textview

Example format xml in file string and colors

<!-- /res/values/strings.xml -->
<string name="status_stop">Stopped</string>
<string name="status_running">Running</string>
<string name="status_error">Error</string>

<!-- /res/values/colors.xml -->
<color name="status_stop">#8E8E93</color>
<color name="status_running">#4CD964</color>
<color name="status_error">#FF3B30</color>

Function to get color from xml with validation for android 6.0 and above

public static int getColorWrapper(Context context, int id) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {//if actual version is >= 6.0
            return context.getColor(id);
        } else {
            //noinspection deprecation
            return context.getResources().getColor(id);
        }
    }

Example:

TextView status = (TextView)findViewById(R.id.tvstatus);
status.setTextColor(getColorWrapper(myactivity.this,R.color.status_stop));

Reference: getColor(int id) deprecated on Android 6.0 Marshmallow (API 23)

What does axis in pandas mean?

Axis in view of programming is the position in the shape tuple. Here is an example:

import numpy as np

a=np.arange(120).reshape(2,3,4,5)

a.shape
Out[3]: (2, 3, 4, 5)

np.sum(a,axis=0).shape
Out[4]: (3, 4, 5)

np.sum(a,axis=1).shape
Out[5]: (2, 4, 5)

np.sum(a,axis=2).shape
Out[6]: (2, 3, 5)

np.sum(a,axis=3).shape
Out[7]: (2, 3, 4)

Mean on the axis will cause that dimension to be removed.

Referring to the original question, the dff shape is (1,2). Using axis=1 will change the shape to (1,).

Fetch API request timeout?

If you haven't configured timeout in your code, It will be the default request timeout of your browser.

1) Firefox - 90 seconds

Type about:config in Firefox URL field. Find the value corresponding to key network.http.connection-timeout

2) Chrome - 300 seconds

Source

Converting pixels to dp

 
/**
 * This method converts dp unit to equivalent pixels, depending on device density. 
 * 
 * @param dp A value in dp (density independent pixels) unit. Which we need to convert into pixels
 * @param context Context to get resources and device specific display metrics
 * @return A float value to represent px equivalent to dp depending on device density
 */
public static float convertDpToPixel(float dp, Context context){
    return dp * ((float) context.getResources().getDisplayMetrics().densityDpi / DisplayMetrics.DENSITY_DEFAULT);
}

/**
 * This method converts device specific pixels to density independent pixels.
 * 
 * @param px A value in px (pixels) unit. Which we need to convert into db
 * @param context Context to get resources and device specific display metrics
 * @return A float value to represent dp equivalent to px value
 */
public static float convertPixelsToDp(float px, Context context){
    return px / ((float) context.getResources().getDisplayMetrics().densityDpi / DisplayMetrics.DENSITY_DEFAULT);
}

Display all dataframe columns in a Jupyter Python Notebook

Python 3.x for large (but not too large) DataFrames

Maybe because I have an older version of pandas but on Jupyter notebook this work for me

import pandas as pd
from IPython.core.display import HTML

df=pd.read_pickle('Data1')
display(HTML(df.to_html()))

How to Delete a topic in apache kafka

Deletion of a topic has been supported since 0.8.2.x version. You have to enable topic deletion (setting delete.topic.enable to true) on all brokers first.

Note: Ever since 1.0.x, the functionality being stable, delete.topic.enable is by default true.

Follow this step by step process for manual deletion of topics

  1. Stop Kafka server
  2. Delete the topic directory, on each broker (as defined in the logs.dirs and log.dir properties) with rm -rf command
  3. Connect to Zookeeper instance: zookeeper-shell.sh host:port
  4. From within the Zookeeper instance:
    1. List the topics using: ls /brokers/topics
    2. Remove the topic folder from ZooKeeper using: rmr /brokers/topics/yourtopic
    3. Exit the Zookeeper instance (Ctrl+C)
  5. Restart Kafka server
  6. Confirm if it was deleted or not by using this command kafka-topics.sh --list --zookeeper host:port

default value for struct member in C

Another approach, if the struct allows it, is to use a #define with the default values inside:

#define MYSTRUCT_INIT { 0, 0, true }

typedef struct
{
    int id;
    int flag;
    bool foo;
} MyStruct;

Use:

MyStruct val = MYSTRUCT_INIT;

Uncaught TypeError: $(...).datepicker is not a function(anonymous function)

What went wrong?

When you include jQuery the first time:

<script src="http://code.jquery.com/jquery-1.9.1.js"></script>
<script src="http://code.jquery.com/ui/1.11.0/jquery-ui.js"></script>

The second script plugs itself into jQuery, and "adds" $(...).datepicker.

But then you are including jQuery once again:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>

It undoes the plugging in and therefore $(...).datepicker becomes undefined.

Although the first $(document).ready block appears before that, the anonymous callback function body is not executed until all scripts are loaded, and by then $(...) (window.$ to be precise) is referring to the most recently loaded jQuery.

You would not run into this if you called $('.dateinput').datepicker immediately rather than in $(document).ready callback, but then you'd need to make sure that the target element (with class dateinput) is already in the document before the script, and it's generally advised to use the ready callback.

Solution

If you want to use datepicker from jquery-ui, it would probably make most sense to include the jquery-ui script after bootstrap. jquery-ui 1.11.4 is compatible with jquery 1.6+ so it will work fine.

Alternatively (in particular if you are not using jquery-ui for anything else), you could try bootstrap-datepicker.

ExpressJS - throw er Unhandled error event

Simple just check your teminal in Visual Studio Code Because me was running my node app and i hibernate my laptop then next morning i turn my laptop on back to development of software. THen i run the again command nodemon app.js First waas running from night and the second was running my latest command so two command prompts are listening to same ports that's why you are getting this issue. Simple Close one termianl or all terminal then run your node app.js or nodemon app.js

How can I get nth element from a list?

The straight answer was already given: Use !!.

However newbies often tend to overuse this operator, which is expensive in Haskell (because you work on single linked lists, not on arrays). There are several useful techniques to avoid this, the easiest one is using zip. If you write zip ["foo","bar","baz"] [0..], you get a new list with the indices "attached" to each element in a pair: [("foo",0),("bar",1),("baz",2)], which is often exactly what you need.

setting y-axis limit in matplotlib

Just for fine tuning. If you want to set only one of the boundaries of the axis and let the other boundary unchanged, you can choose one or more of the following statements

plt.xlim(right=xmax) #xmax is your value
plt.xlim(left=xmin) #xmin is your value
plt.ylim(top=ymax) #ymax is your value
plt.ylim(bottom=ymin) #ymin is your value

Take a look at the documentation for xlim and for ylim

java.sql.SQLException: Exhausted Resultset

Problem behind the error: If you are trying to access Oracle database you will not able to access inserted data until the transaction has been successful and to complete the transaction you have to fire a commit query after inserting the data into the table. Because Oracle database is not on auto commit mode by default.

Solution:

Go to SQL PLUS and follow the following queries..

SQL*Plus: Release 11.2.0.1.0 Production on Tue Nov 28 15:29:43 2017

Copyright (c) 1982, 2010, Oracle.  All rights reserved.

Enter user-name: scott
Enter password:

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> desc empdetails;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 ENO                                                NUMBER(38)
 ENAME                                              VARCHAR2(20)
 SAL                                                FLOAT(126)

SQL> insert into empdetails values(1010,'John',45000.00);

1 row created.

SQL> commit;

Commit complete.

Keep background image fixed during scroll using css

Just add background-attachment to your code

body {
    background-position: center;
    background-image: url(../images/images5.jpg);
    background-attachment: fixed;
}

Select single item from a list

just saw this now, if you are working with a list of object you can try this

 public class user
{
    public string username { get; set; }
    public string password { get; set; }
}

  List<user> userlist = new List<user>();

        userlist.Add(new user { username = "macbruno", password = "1234" });
        userlist.Add(new user { username = "james", password = "5678" });
        string myusername = "james";
        string mypassword = "23432";

  user theUser = userlist.Find(
            delegate (user thisuser)
            {
                return thisuser.username== myusername && thisuser.password == mypassword;
            }
            );

            if (theUser != null)
            {
               Dosomething();
            }
            else
            {
                DoSomethingElse();

            }

Creating watermark using html and css

you may use opacity:0.5;//what ever you wish between 0 and 1 for this.

working Fiddle

'this' is undefined in JavaScript class methods

How are you calling the start function?

This should work (new is the key)

var o = new Request(destination, stay_open);
o.start();

If you directly call it like Request.prototype.start(), this will refer to the global context (window in browsers).

Also, if this is undefined, it results in an error. The if expression does not evaluate to false.

Update: this object is not set based on declaration, but by invocation. What it means is that if you assign the function property to a variable like x = o.start and call x(), this inside start no longer refers to o. This is what happens when you do setTimeout. To make it work, do this instead:

 var o = new Request(...);
 setTimeout(function() { o.start(); }, 1000);

Import and insert sql.gz file into database with putty

Creating a Dump File SQL.gz on the current server

$ sudo apt-get install pigz pv

$ pv | mysqldump --user=<yourdbuser> --password=<yourdbpassword> <currentexistingdbname> --single-transaction --routines --triggers --events --quick --opt -Q --flush-logs --allow-keywords --hex-blob --order-by-primary --skip-comments --skip-disable-keys --skip-add-locks --extended-insert --log-error=/var/log/mysql/<dbname>_backup.log | pigz > /path/to/folder/<dbname>_`date +\%Y\%m\%d_\%H\%M`.sql.gz

Optional: Command Arguments for connection

--host=127.0.0.1 / localhost / IP Address of the Dump Server
--port=3306

Importing the dumpfile created above to a different Server

$ sudo apt-get install pigz pv

$ zcat /path/to/folder/<dbname>_`date +\%Y\%m\%d_\%H\%M`.sql.gz | pv | mysql --user=<yourdbuser> --password=<yourdbpassword> --database=<yournewdatabasename> --compress --reconnect --unbuffered --net_buffer_length=1048576 --max_allowed_packet=1073741824 --connect_timeout=36000 --line-numbers --wait --init-command="SET GLOBAL net_buffer_length=1048576;SET GLOBAL max_allowed_packet=1073741824;SET FOREIGN_KEY_CHECKS=0;SET UNIQUE_CHECKS = 0;SET AUTOCOMMIT = 1;FLUSH NO_WRITE_TO_BINLOG QUERY CACHE, STATUS, SLOW LOGS, GENERAL LOGS, ERROR LOGS, ENGINE LOGS, BINARY LOGS, LOGS;"

Optional: Command Arguments for connection

--host=127.0.0.1 / localhost / IP Address of the Import Server
--port=3306

mysql: [Warning] Using a password on the command line interface can be insecure. 1.0GiB 00:06:51 [8.05MiB/s] [<=> ]

The optional software packages are helpful to import your database SQL file faster

  • with a progress view (pv)
  • Parallel gzip (pigz/unpigz) to gzip/gunzip files in parallel

for faster zipping of the output

Display PDF file inside my android application

This is the perfect solution that worked for me without any 3rd party library.

Rendering a PDF Document in Android Activity/Fragment (Using PdfRenderer)

How to wrap text using CSS?

If you type "AAAAAAAAAAAAAAAAAAAAAARRRRRRRRRRRRRRRRRRRRRRGGGGGGGGGGGGGGGGGGGGG" this will produce:

AARRRRRRRRRRRRRRRRRRRR
RRGGGGGGGGGGGGGGGGGGGG
G

I have taken my example from a couple different websites on google. I have tested this on ff 5.0, IE 8.0, and Chrome 10. It works on all of them.

.wrapword {
    white-space: -moz-pre-wrap !important;  /* Mozilla, since 1999 */
    white-space: -pre-wrap;      /* Opera 4-6 */
    white-space: -o-pre-wrap;    /* Opera 7 */
    white-space: pre-wrap;       /* css-3 */
    word-wrap: break-word;       /* Internet Explorer 5.5+ */
    white-space: -webkit-pre-wrap; /* Newer versions of Chrome/Safari*/
    word-break: break-all;
    white-space: normal;
}

<table style="table-layout:fixed; width:400px">
    <tr>
        <td class="wrapword"></td>
    </tr>
</table>

Single line sftp from terminal

sftp supports batch files.

From the man page:

-b batchfile

Batch mode reads a series of commands from an input batchfile instead of stdin.  
Since it lacks user interaction it should be used in conjunction with non-interactive
authentication.  A batchfile of `-' may be used to indicate standard input.  sftp 
will abort if any of the following commands fail: get, put, rename, ln, rm, mkdir, 
chdir, ls, lchdir, chmod, chown, chgrp, lpwd, df, symlink, and lmkdir.  Termination 
on error can be suppressed on a command by command basis by prefixing the command 
with a `-' character (for example, -rm /tmp/blah*).

"undefined" function declared in another file?

If you're using go run, do go run *.go. It will automatically find all go files in the current working directory, compile and then run your main function.

How to pause a vbscript execution?

You can use a WScript object and call the Sleep method on it:

Set WScript = CreateObject("WScript.Shell")
WScript.Sleep 2000 'Sleeps for 2 seconds

Another option is to import and use the WinAPI function directly (only works in VBA, thanks @Helen):

Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Sleep 2000

Mockito. Verify method arguments

An alternative to ArgumentMatcher is ArgumentCaptor.

Official example:

ArgumentCaptor<Person> argument = ArgumentCaptor.forClass(Person.class);
verify(mock).doSomething(argument.capture());
assertEquals("John", argument.getValue().getName());

A captor can also be defined using the @Captor annotation: 

@Captor ArgumentCaptor<Person> captor;
//... MockitoAnnotations.initMocks(this);
@Test public void test() {
    //...
    verify(mock).doSomething(captor.capture());
    assertEquals("John", captor.getValue().getName());
}

How to get name of calling function/method in PHP?

I needed something to just list the calling classes/methods (working on a Magento project).

While debug_backtrace provides tons of useful information, the amount of information it spewed out for the Magento installation was overwhelming (over 82,000 lines!) Since I was only concerned with the calling function and class, I worked this little solution up:

$callers = debug_backtrace();
foreach( $callers as $call ) {
    echo "<br>" . $call['class'] . '->' . $call['function'];
}

How do you clear the focus in javascript?

Answer: document.activeElement

To do what you want, use document.activeElement.blur()

If you need to support Firefox 2, you can also use this:

function onElementFocused(e)
{
    if (e && e.target)
        document.activeElement = e.target == document ? null : e.target;
} 

if (document.addEventListener) 
    document.addEventListener("focus", onElementFocused, true);

Executing <script> injected by innerHTML after AJAX call

I had a similiar post here, addEventListener load on ajax load WITHOUT jquery

How I solved it was to insert calls to functions within my stateChange function. The page I had setup was 3 buttons that would load 3 different pages into the contentArea. Because I had to know which button was being pressed to load page 1, 2 or 3, I could easily use if/else statements to determine which page is being loaded and then which function to run. What I was trying to do was register different button listeners that would only work when the specific page was loaded because of element IDs..

so...

if (page1 is being loaded, pageload = 1) run function registerListeners1

then the same for page 2 or 3.

How to scroll to top of page with JavaScript/jQuery?

Combination of these two helped me. None of the other answers helped me since i had a sidenav that was not scrolling.

 setTimeout(function () {
        window.scroll({
                        top: 0,
                        left: 0,
                        behavior: 'smooth'
                    });

    document.body.scrollTop = document.documentElement.scrollTop = 0;

}, 15);

Dynamically allocating an array of objects

For building containers you obviously want to use one of the standard containers (such as a std::vector). But this is a perfect example of the things you need to consider when your object contains RAW pointers.

If your object has a RAW pointer then you need to remember the rule of 3 (now the rule of 5 in C++11).

  • Constructor
  • Destructor
  • Copy Constructor
  • Assignment Operator
  • Move Constructor (C++11)
  • Move Assignment (C++11)

This is because if not defined the compiler will generate its own version of these methods (see below). The compiler generated versions are not always useful when dealing with RAW pointers.

The copy constructor is the hard one to get correct (it's non trivial if you want to provide the strong exception guarantee). The Assignment operator can be defined in terms of the Copy Constructor as you can use the copy and swap idiom internally.

See below for full details on the absolute minimum for a class containing a pointer to an array of integers.

Knowing that it is non trivial to get it correct you should consider using std::vector rather than a pointer to an array of integers. The vector is easy to use (and expand) and covers all the problems associated with exceptions. Compare the following class with the definition of A below.

class A
{ 
    std::vector<int>   mArray;
    public:
        A(){}
        A(size_t s) :mArray(s)  {}
};

Looking at your problem:

A* arrayOfAs = new A[5];
for (int i = 0; i < 5; ++i)
{
    // As you surmised the problem is on this line.
    arrayOfAs[i] = A(3);

    // What is happening:
    // 1) A(3) Build your A object (fine)
    // 2) A::operator=(A const&) is called to assign the value
    //    onto the result of the array access. Because you did
    //    not define this operator the compiler generated one is
    //    used.
}

The compiler generated assignment operator is fine for nearly all situations, but when RAW pointers are in play you need to pay attention. In your case it is causing a problem because of the shallow copy problem. You have ended up with two objects that contain pointers to the same piece of memory. When the A(3) goes out of scope at the end of the loop it calls delete [] on its pointer. Thus the other object (in the array) now contains a pointer to memory that has been returned to the system.

The compiler generated copy constructor; copies each member variable by using that members copy constructor. For pointers this just means the pointer value is copied from the source object to the destination object (hence shallow copy).

The compiler generated assignment operator; copies each member variable by using that members assignment operator. For pointers this just means the pointer value is copied from the source object to the destination object (hence shallow copy).

So the minimum for a class that contains a pointer:

class A
{
    size_t     mSize;
    int*       mArray;
    public:
         // Simple constructor/destructor are obvious.
         A(size_t s = 0) {mSize=s;mArray = new int[mSize];}
        ~A()             {delete [] mArray;}

         // Copy constructor needs more work
         A(A const& copy)
         {
             mSize  = copy.mSize;
             mArray = new int[copy.mSize];

             // Don't need to worry about copying integers.
             // But if the object has a copy constructor then
             // it would also need to worry about throws from the copy constructor.
             std::copy(&copy.mArray[0],&copy.mArray[c.mSize],mArray);

         }

         // Define assignment operator in terms of the copy constructor
         // Modified: There is a slight twist to the copy swap idiom, that you can
         //           Remove the manual copy made by passing the rhs by value thus
         //           providing an implicit copy generated by the compiler.
         A& operator=(A rhs) // Pass by value (thus generating a copy)
         {
             rhs.swap(*this); // Now swap data with the copy.
                              // The rhs parameter will delete the array when it
                              // goes out of scope at the end of the function
             return *this;
         }
         void swap(A& s) noexcept
         {
             using std::swap;
             swap(this.mArray,s.mArray);
             swap(this.mSize ,s.mSize);
         }

         // C++11
         A(A&& src) noexcept
             : mSize(0)
             , mArray(NULL)
         {
             src.swap(*this);
         }
         A& operator=(A&& src) noexcept
         {
             src.swap(*this);     // You are moving the state of the src object
                                  // into this one. The state of the src object
                                  // after the move must be valid but indeterminate.
                                  //
                                  // The easiest way to do this is to swap the states
                                  // of the two objects.
                                  //
                                  // Note: Doing any operation on src after a move 
                                  // is risky (apart from destroy) until you put it 
                                  // into a specific state. Your object should have
                                  // appropriate methods for this.
                                  // 
                                  // Example: Assignment (operator = should work).
                                  //          std::vector() has clear() which sets
                                  //          a specific state without needing to
                                  //          know the current state.
             return *this;
         }   
 }

Using two values for one switch case statement

The brackets are unnecessary. Just do

case text1:
case text4:
  doSomethingHere();
  break;
case text2:
  doSomethingElse()
  break;

If anyone is curious, this is called a case fallthrough. The ability to do this is the reason why break; is necessary to end case statements. For more information, see the wikipedia article http://en.wikipedia.org/wiki/Switch_statement.

SQL JOIN, GROUP BY on three tables to get totals

First of all, shouldn't there be a CustomerId in the Invoices table? As it is, You can't perform this query for Invoices that have no payments on them as yet. If there are no payments on an invoice, that invoice will not even show up in the ouput of the query, even though it's an outer join...

Also, When a customer makes a payment, how do you know what Invoice to attach it to ? If the only way is by the InvoiceId on the stub that arrives with the payment, then you are (perhaps inappropriately) associating Invoices with the customer that paid them, rather than with the customer that ordered them... . (Sometimes an invoice can be paid by someone other than the customer who ordered the services)

Converting Swagger specification JSON to HTML documentation

For Swagger API 3.0, generating Html2 client code from online Swagger Editor works great for me!

When should you use constexpr capability in C++11?

Suppose it does something a little more complicated.

constexpr int MeaningOfLife ( int a, int b ) { return a * b; }

const int meaningOfLife = MeaningOfLife( 6, 7 );

Now you have something that can be evaluated down to a constant while maintaining good readability and allowing slightly more complex processing than just setting a constant to a number.

It basically provides a good aid to maintainability as it becomes more obvious what you are doing. Take max( a, b ) for example:

template< typename Type > constexpr Type max( Type a, Type b ) { return a < b ? b : a; }

Its a pretty simple choice there but it does mean that if you call max with constant values it is explicitly calculated at compile time and not at runtime.

Another good example would be a DegreesToRadians function. Everyone finds degrees easier to read than radians. While you may know that 180 degrees is 3.14159265 (Pi) in radians it is much clearer written as follows:

const float oneeighty = DegreesToRadians( 180.0f );

Lots of good info here:

http://en.cppreference.com/w/cpp/language/constexpr

How do I start my app on startup?

Another approach is to use android.intent.action.USER_PRESENT instead of android.intent.action.BOOT_COMPLETED to avoid slow downs during the boot process. But this is only true if the user has enabled the lock Screen - otherwise this intent is never broadcasted.

Reference blog - The Problem With Android’s ACTION_USER_PRESENT Intent

Why can templates only be implemented in the header file?

Plenty correct answers here, but I wanted to add this (for completeness):

If you, at the bottom of the implementation cpp file, do explicit instantiation of all the types the template will be used with, the linker will be able to find them as usual.

Edit: Adding example of explicit template instantiation. Used after the template has been defined, and all member functions has been defined.

template class vector<int>;

This will instantiate (and thus make available to the linker) the class and all its member functions (only). Similar syntax works for template functions, so if you have non-member operator overloads you may need to do the same for those.

The above example is fairly useless since vector is fully defined in headers, except when a common include file (precompiled header?) uses extern template class vector<int> so as to keep it from instantiating it in all the other (1000?) files that use vector.

How do files get into the External Dependencies in Visual Studio C++?

 
To resolve external dependencies within project. below things are important..
1. The compiler should know that where are header '.h' files located in workspace.
2. The linker able to find all specified  all '.lib' files & there names for current project.

So, Developer has to specify external dependencies for Project as below..

1. Select Project in Solution explorer.

2 . Project Properties -> Configuration Properties -> C/C++ -> General
specify all header files in "Additional Include Directories".

3.  Project Properties -> Configuration Properties -> Linker -> General
specify relative path for all lib files in "Additional Library Directories".

enter image description here enter image description here

How to Call a JS function using OnClick event

Inline code takes higher precedence than the other ones. To call your other function func () call it from the f1 ().

Inside your function, add a line,

function fun () {
// Your code here
}

function f1()
    {
       alert("f1 called");
       //form validation that recalls the page showing with supplied inputs.    

fun ();

    }

Rewriting your whole code,

 <!DOCTYPE html>
    <html>
      <head>

      <script>

       function fun()
        {
         alert("hello");
         //validation code to see State field is mandatory.  
        }   

        function f1()
        {
           alert("f1 called");
           //form validation that recalls the page showing with supplied inputs.   
           fun (); 
        }

      </script>
      </head>
      <body>
       <form name="form1" id="form1" method="post">

         State: <select id="state ID">
                   <option></option>
                   <option value="ap">ap</option>
                   <option value="bp">bp</option>
                </select>
       </form>
       <table><tr><td id="Save" onclick="f1()">click</td></tr></table>

      </body>
</html>

How to delete a folder in C++?

Delete folder (sub_folders and files) in Windows (VisualC++) not using Shell APIs, this is the best working sample:

#include <string>
#include <iostream>

#include <windows.h>
#include <conio.h>


int DeleteDirectory(const std::string &refcstrRootDirectory,
                    bool              bDeleteSubdirectories = true)
{
  bool            bSubdirectory = false;       // Flag, indicating whether
                                               // subdirectories have been found
  HANDLE          hFile;                       // Handle to directory
  std::string     strFilePath;                 // Filepath
  std::string     strPattern;                  // Pattern
  WIN32_FIND_DATA FileInformation;             // File information


  strPattern = refcstrRootDirectory + "\\*.*";
  hFile = ::FindFirstFile(strPattern.c_str(), &FileInformation);
  if(hFile != INVALID_HANDLE_VALUE)
  {
    do
    {
      if(FileInformation.cFileName[0] != '.')
      {
        strFilePath.erase();
        strFilePath = refcstrRootDirectory + "\\" + FileInformation.cFileName;

        if(FileInformation.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
        {
          if(bDeleteSubdirectories)
          {
            // Delete subdirectory
            int iRC = DeleteDirectory(strFilePath, bDeleteSubdirectories);
            if(iRC)
              return iRC;
          }
          else
            bSubdirectory = true;
        }
        else
        {
          // Set file attributes
          if(::SetFileAttributes(strFilePath.c_str(),
                                 FILE_ATTRIBUTE_NORMAL) == FALSE)
            return ::GetLastError();

          // Delete file
          if(::DeleteFile(strFilePath.c_str()) == FALSE)
            return ::GetLastError();
        }
      }
    } while(::FindNextFile(hFile, &FileInformation) == TRUE);

    // Close handle
    ::FindClose(hFile);

    DWORD dwError = ::GetLastError();
    if(dwError != ERROR_NO_MORE_FILES)
      return dwError;
    else
    {
      if(!bSubdirectory)
      {
        // Set directory attributes
        if(::SetFileAttributes(refcstrRootDirectory.c_str(),
                               FILE_ATTRIBUTE_NORMAL) == FALSE)
          return ::GetLastError();

        // Delete directory
        if(::RemoveDirectory(refcstrRootDirectory.c_str()) == FALSE)
          return ::GetLastError();
      }
    }
  }

  return 0;
}


int main()
{
  int         iRC                  = 0;
  std::string strDirectoryToDelete = "c:\\mydir";


  // Delete 'c:\mydir' without deleting the subdirectories
  iRC = DeleteDirectory(strDirectoryToDelete, false);
  if(iRC)
  {
    std::cout << "Error " << iRC << std::endl;
    return -1;
  }

  // Delete 'c:\mydir' and its subdirectories
  iRC = DeleteDirectory(strDirectoryToDelete);
  if(iRC)
  {
    std::cout << "Error " << iRC << std::endl;
    return -1;
  }

  // Wait for keystroke
  _getch();

  return 0;
}

Source: http://www.codeguru.com/forum/showthread.php?t=239271

Docker - Container is not running

Here's a solution when the docker container exits normally and you can edit the Dockerfile.

Generally, when a docker container is run, an application is served by running a command. From the Dockerfile reference,

Both CMD and ENTRYPOINT instructions define what command gets executed when running a container. ... Dockerfile should specify at least one of CMD or ENTRYPOINT commands.

When you build a image and not specify any command with CMD or ENTRYPOINT, the base image's CMD or ENTRYPOINT command would be executed.

For example, the Official Ubuntu Dockerfile has CMD ["/bin/bash"] (https://hub.docker.com/_/ubuntu). Now, the bin/bash/ command can accept input and docker run -it IMAGE_ID command attaches STDIN to the container. The result is that you get an interactive terminal and the container keeps running.

When a command with CMD or ENTRYPOINT is specified in the Dockerfile, this command gets executed when running the container. Now, if this command can finish without requiring any input, it will finish and the container will exit. docker run -it IMAGE_ID will NOT provide the interactive terminal in this case. An example would be the docker image built from the Dockerfile below-

FROM ubuntu
ENTRYPOINT echo hello

If you need to go to the terminal of this image, you will need to keep the container running by modifying the entrypoint command.

FROM ubuntu
ENTRYPOINT echo hello && sleep infinity

After running the container normally with docker run IMAGE_ID, you can just go to another terminal and use docker exec -it CONTAINER_ID bash to get the container's terminal.

How to call a Parent Class's method from Child Class in Python?

Python also has super as well:

super(type[, object-or-type])

Return a proxy object that delegates method calls to a parent or sibling class of type. This is useful for accessing inherited methods that have been overridden in a class. The search order is same as that used by getattr() except that the type itself is skipped.

Example: 

class A(object):     # deriving from 'object' declares A as a 'new-style-class'
    def foo(self):
        print "foo"

class B(A):
    def foo(self):
        super(B, self).foo()   # calls 'A.foo()'

myB = B()
myB.foo()

Calculate the display width of a string in Java

Use the getWidth method in the following class:

import java.awt.*;
import java.awt.geom.*;
import java.awt.font.*;

class StringMetrics {

  Font font;
  FontRenderContext context;

  public StringMetrics(Graphics2D g2) {

    font = g2.getFont();
    context = g2.getFontRenderContext();
  }

  Rectangle2D getBounds(String message) {

    return font.getStringBounds(message, context);
  }

  double getWidth(String message) {

    Rectangle2D bounds = getBounds(message);
    return bounds.getWidth();
  }

  double getHeight(String message) {

    Rectangle2D bounds = getBounds(message);
    return bounds.getHeight();
  }

}

MySQL Removing Some Foreign keys

As explained here, seems the foreign key constraint has to be dropped by constraint name and not the index name.

The syntax is:

ALTER TABLE footable DROP FOREIGN KEY fooconstraint;

Error message "Forbidden You don't have permission to access / on this server"

If you are using a WAMP server then try this:

  • Single click on the WAMP server icon at the taskbar

  • Select the option put online

  • Your server will restart automatically

  • Then try to access your localwebsite

How to filter object array based on attributes?

here is the working fiddle which works fine in IE8 using jquery MAP function

http://jsfiddle.net/533135/Cj4j7/

json.HOMES = $.map(json.HOMES, function(val, key) {
    if (Number(val.price) <= 1000
            && Number(val.sqft) >= 500
            && Number(val.num_of_beds) >=2
            && Number(val.num_of_baths ) >= 2.5)
        return val;
});

How can I tell AngularJS to "refresh"

Why $apply should be called?

TL;DR: $apply should be called whenever you want to apply changes made outside of Angular world.

Just to update @Dustin's answer, here is an explanation of what $apply exactly does and why it works.

$apply() is used to execute an expression in AngularJS from outside of the AngularJS framework. (For example from browser DOM events, setTimeout, XHR or third party libraries). Because we are calling into the AngularJS framework we need to perform proper scope life cycle of exception handling, executing watches.

Angular allows any value to be used as a binding target. Then at the end of any JavaScript code turn, it checks to see if the value has changed. That step that checks to see if any binding values have changed actually has a method, $scope.$digest()1. We almost never call it directly, as we use $scope.$apply() instead (which will call $scope.$digest).

Angular only monitors variables used in expressions and anything inside of a $watch living inside the scope. So if you are changing the model outside of the Angular context, you will need to call $scope.$apply() for those changes to be propagated, otherwise Angular will not know that they have been changed thus the binding will not be updated2.

How to give color to each class in scatter plot in R?

Assuming the class variable is z, you can use: 

with(df, plot(x, y, col = z))

however, it's important that z is a factor variable, as R internally stores factors as integers.

This way, 1 is 'black', 2 is 'red', 3 is 'green, ....

Effective way to find any file's Encoding

Providing the implementation details for the steps proposed by @CodesInChaos:

1) Check if there is a Byte Order Mark

2) Check if the file is valid UTF8

3) Use the local "ANSI" codepage (ANSI as Microsoft defines it)

Step 2 works because most non ASCII sequences in codepages other that UTF8 are not valid UTF8. https://stackoverflow.com/a/4522251/867248 explains the tactic in more details.

using System; using System.IO; using System.Text;

// Using encoding from BOM or UTF8 if no BOM found,
// check if the file is valid, by reading all lines
// If decoding fails, use the local "ANSI" codepage

public string DetectFileEncoding(Stream fileStream)
{
    var Utf8EncodingVerifier = Encoding.GetEncoding("utf-8", new EncoderExceptionFallback(), new DecoderExceptionFallback());
    using (var reader = new StreamReader(fileStream, Utf8EncodingVerifier,
           detectEncodingFromByteOrderMarks: true, leaveOpen: true, bufferSize: 1024))
    {
        string detectedEncoding;
        try
        {
            while (!reader.EndOfStream)
            {
                var line = reader.ReadLine();
            }
            detectedEncoding = reader.CurrentEncoding.BodyName;
        }
        catch (Exception e)
        {
            // Failed to decode the file using the BOM/UT8. 
            // Assume it's local ANSI
            detectedEncoding = "ISO-8859-1";
        }
        // Rewind the stream
        fileStream.Seek(0, SeekOrigin.Begin);
        return detectedEncoding;
   }
}


[Test]
public void Test1()
{
    Stream fs = File.OpenRead(@".\TestData\TextFile_ansi.csv");
    var detectedEncoding = DetectFileEncoding(fs);

    using (var reader = new StreamReader(fs, Encoding.GetEncoding(detectedEncoding)))
    {
       // Consume your file
        var line = reader.ReadLine();
        ...

AngularJS - Binding radio buttons to models with boolean values

 
 <label class="rate-hit">
     <input type="radio" ng-model="st.result" ng-value="true" ng-checked="st.result">
     Hit
 </label>
 &nbsp;&nbsp;
 <label class="rate-miss">
     <input type="radio" ng-model="st.result" ng-value="false" ng-checked="!st.result">
     Miss
 </label>

Select parent element of known element in Selenium

Let's consider your DOM as

<a>
    <!-- some other icons and texts -->
    <span>Close</span>
</a>

Now that you need to select parent tag 'a' based on <span> text, then use

driver.findElement(By.xpath("//a[.//span[text()='Close']]"));

Explanation: Select the node based on its child node's value

Java - Relative path of a file in a java web application

If you have a path for that file in the web server, you can get the real path in the server's file system using ServletContext.getRealPath(). Note that it is not guaranteed to work in every container (as a container is not required to unpack the WAR file and store the content in the file system - most do though). And I guess it won't work with files in /WEB-INF, as they don't have a virtual path.

The alternative would be to use ServletContext.getResource() which returns a URI. This URI may be a 'file:' URL, but there's no guarantee for that.

How do I format currencies in a Vue component?

You can use this example

formatPrice(value) {
  return value.toString().replace(/(\d)(?=(\d{3})+(?!\d))/g, '$1,');
},

SQL query question: SELECT ... NOT IN

 
SELECT distinct idCustomer FROM reservations
WHERE DATEPART ( hour, insertDate) < 2
  and idCustomer is not null

Make sure your list parameter does not contain null values.

Here's an explanation:

WHERE field1 NOT IN (1, 2, 3, null)

is the same as:

WHERE NOT (field1 = 1 OR field1 = 2 OR field1 = 3 OR field1 = null)
  • That last comparision evaluates to null.
  • That null is OR'd with the rest of the boolean expression, yielding null. (*)
  • null is negated, yielding null.
  • null is not true - the where clause only keeps true rows, so all rows are filtered.

(*) Edit: this explanation is pretty good, but I wish to address one thing to stave off future nit-picking. (TRUE OR NULL) would evaluate to TRUE. This is relevant if field1 = 3, for example. That TRUE value would be negated to FALSE and the row would be filtered.

CSS 3 slide-in from left transition

Use CSS3 2D transform to avoid performance issues (mobile)

A common pitfall is to animate left/top/right/bottom properties instead of using to achieve the same effect. For a variety of reasons, the semantics of transforms make them easier to offload, but left/top/right/bottom are much more difficult.

Source: Mozilla Developer Network (MDN)

Demo:

_x000D_
_x000D_ 
var $slider = document.getElementById('slider');
var $toggle = document.getElementById('toggle');

$toggle.addEventListener('click', function() {
    var isOpen = $slider.classList.contains('slide-in');

    $slider.setAttribute('class', isOpen ? 'slide-out' : 'slide-in');
});
_x000D_ 
#slider {
    position: absolute;
    width: 100px;
    height: 100px;
    background: blue;
    transform: translateX(-100%);
    -webkit-transform: translateX(-100%);
}

.slide-in {
    animation: slide-in 0.5s forwards;
    -webkit-animation: slide-in 0.5s forwards;
}

.slide-out {
    animation: slide-out 0.5s forwards;
    -webkit-animation: slide-out 0.5s forwards;
}
    
@keyframes slide-in {
    100% { transform: translateX(0%); }
}

@-webkit-keyframes slide-in {
    100% { -webkit-transform: translateX(0%); }
}
    
@keyframes slide-out {
    0% { transform: translateX(0%); }
    100% { transform: translateX(-100%); }
}

@-webkit-keyframes slide-out {
    0% { -webkit-transform: translateX(0%); }
    100% { -webkit-transform: translateX(-100%); }
}
_x000D_ 
<div id="slider" class="slide-in">
    <ul>
        <li>Lorem</li>
        <li>Ipsum</li>
        <li>Dolor</li>
    </ul>
</div>

<button id="toggle" style="position:absolute; top: 120px;">Toggle</button>
_x000D_
_x000D_
_x000D_

XML Schema minOccurs / maxOccurs default values

New, expanded answer to an old, commonly asked question...

Default Values

  • Occurrence constraints minOccurs and maxOccurs default to 1.

Common Cases Explained

<xsd:element name="A"/>

means A is required and must appear exactly once.

<xsd:element name="A" minOccurs="0"/>

means A is optional and may appear at most once.

 <xsd:element name="A" maxOccurs="unbounded"/>

means A is required and may repeat an unlimited number of times.

 <xsd:element name="A" minOccurs="0" maxOccurs="unbounded"/>

means A is optional and may repeat an unlimited number of times.

See Also

  • W3C XML Schema Part 0: Primer

    In general, an element is required to appear when the value of minOccurs is 1 or more. The maximum number of times an element may appear is determined by the value of a maxOccurs attribute in its declaration. This value may be a positive integer such as 41, or the term unbounded to indicate there is no maximum number of occurrences. The default value for both the minOccurs and the maxOccurs attributes is 1. Thus, when an element such as comment is declared without a maxOccurs attribute, the element may not occur more than once. Be sure that if you specify a value for only the minOccurs attribute, it is less than or equal to the default value of maxOccurs, i.e. it is 0 or 1. Similarly, if you specify a value for only the maxOccurs attribute, it must be greater than or equal to the default value of minOccurs, i.e. 1 or more. If both attributes are omitted, the element must appear exactly once.

  • W3C XML Schema Part 1: Structures Second Edition 

    <element
  maxOccurs = (nonNegativeInteger | unbounded)  : 1
  minOccurs = nonNegativeInteger : 1
  >

</element>

How do I change the string representation of a Python class?

This is not as easy as it seems, some core library functions don't work when only str is overwritten (checked with Python 2.7), see this thread for examples How to make a class JSON serializable Also, try this

import json

class A(unicode):
    def __str__(self):
        return 'a'
    def __unicode__(self):
        return u'a'
    def __repr__(self):
        return 'a'

a = A()
json.dumps(a)

produces

'""'

and not

'"a"'

as would be expected.

EDIT: answering mchicago's comment:

unicode does not have any attributes -- it is an immutable string, the value of which is hidden and not available from high-level Python code. The json module uses re for generating the string representation which seems to have access to this internal attribute. Here's a simple example to justify this:

b = A('b') print b

produces

'a'

while

json.dumps({'b': b})

produces

{"b": "b"}

so you see that the internal representation is used by some native libraries, probably for performance reasons.

See also this for more details: http://www.laurentluce.com/posts/python-string-objects-implementation/

What's the difference between struct and class in .NET?

Well, for starters, a struct is passed by value rather than by reference. Structs are good for relatively simple data structures, while classes have a lot more flexibility from an architectural point of view via polymorphism and inheritance.

Others can probably give you more detail than I, but I use structs when the structure that I am going for is simple.

Python-Requests close http connection

I think a more reliable way of closing a connection is to tell the sever explicitly to close it in a way compliant with HTTP specification:

HTTP/1.1 defines the "close" connection option for the sender to signal that the connection will be closed after completion of the response. For example,

   Connection: close

in either the request or the response header fields indicates that the connection SHOULD NOT be considered `persistent' (section 8.1) after the current request/response is complete.

The Connection: close header is added to the actual request:

r = requests.post(url=url, data=body, headers={'Connection':'close'})

Click to call html

tl;dr What to do in modern (2018) times? Assume tel: is supported, use it and forget about anything else.

The tel: URI scheme RFC5431 (as well as sms: but also feed:, maps:, youtube: and others) is handled by protocol handlers (as mailto: and http: are).

They're unrelated to HTML5 specification (it has been out there from 90s and documented first time back in 2k with RFC2806) then you can't check for their support using tools as modernizr. A protocol handler may be installed by an application (for example Skype installs a callto: protocol handler with same meaning and behaviour of tel: but it's not a standard), natively supported by browser or installed (with some limitations) by website itself.

What HTML5 added is support for installing custom web based protocol handlers (with registerProtocolHandler() and related functions) simplifying also the check for their support through isProtocolHandlerRegistered() function.

There is some easy ways to determine if there is an handler or not:" How to detect browser's protocol handlers?).

In general what I suggest is:

  1. If you're running on a mobile device then you can safely assume tel: is supported (yes, it's not true for very old devices but IMO you can ignore them).
  2. If JS isn't active then do nothing.
  3. If you're running on desktop browsers then you can use one of the techniques in the linked post to determine if it's supported.
  4. If tel: isn't supported then change links to use callto: and repeat check desctibed in 3.
  5. If tel: and callto: aren't supported (or - in a desktop browser - you can't detect their support) then simply remove that link replacing URL in href with javascript:void(0) and (if number isn't repeated in text span) putting, telephone number in title. Here HTML5 microdata won't help users (just search engines). Note that newer versions of Skype handle both callto: and tel:.

Please note that (at least on latest Windows versions) there is always a - fake - registered protocol handler called App Picker (that annoying window that let you choose with which application you want to open an unknown file). This may vanish your tests so if you don't want to handle Windows environment as a special case you can simplify this process as:

  1. If you're running on a mobile device then assume tel: is supported.
  2. If you're running on desktop then replace tel: with callto:. then drop tel: or leave it as is (assuming there are good chances Skype is installed).

@Media min-width & max-width

If website on small devices behavior like desktop screen then you have to put this meta tag into header before 

<meta name="viewport" content="width=device-width, initial-scale=1">

For media queries you can set this as

this will cover your all mobile/cellphone widths

 @media only screen and (min-width: 200px) and (max-width: 767px)  {
    //Put your CSS here for 200px to 767px width devices (cover all width between 200px to 767px //
   
    }

For iPad and iPad pro you have to use

  @media only screen and (min-width: 768px) and (max-width: 1024px)  {
        //Put your CSS here for 768px to 1024px width devices(covers all width between 768px to 1024px //   
  }

If you want to add css for Landscape mode you can add this

and (orientation : landscape)

  @media only screen and (min-width: 200px) and (max-width: 767px) and (orientation : portrait) {
        //Put your CSS here for 200px to 767px width devices (cover all mobile portrait width //        
  }

Get current date in Swift 3?

You say in a comment you want to get "15.09.2016".

For this, use Date and DateFormatter:

let date = Date()
let formatter = DateFormatter()

Give the format you want to the formatter:

formatter.dateFormat = "dd.MM.yyyy"

Get the result string:

let result = formatter.string(from: date)

Set your label:

label.text = result

Result:

15.09.2016

How to display text in pygame?

There's also the pygame.freetype module which is more modern, works with more fonts and offers additional functionality.

Create a font object with pygame.freetype.SysFont() or pygame.freetype.Font if the font is inside of your game directory.

You can render the text either with the render method similarly to the old pygame.font.Font.render or directly onto the target surface with render_to.

import pygame
import pygame.freetype  # Import the freetype module.


pygame.init()
screen = pygame.display.set_mode((800, 600))
GAME_FONT = pygame.freetype.Font("your_font.ttf", 24)
running =  True

while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    screen.fill((255,255,255))
    # You can use `render` and then blit the text surface ...
    text_surface, rect = GAME_FONT.render("Hello World!", (0, 0, 0))
    screen.blit(text_surface, (40, 250))
    # or just `render_to` the target surface.
    GAME_FONT.render_to(screen, (40, 350), "Hello World!", (0, 0, 0))

    pygame.display.flip()

pygame.quit()

OS X Bash, 'watch' command

Try this:

#!/bin/bash
# usage: watch [-n integer] COMMAND

case $# in
    0)
        echo "Usage $0 [-n int] COMMAND"
        ;;
    *)      
        sleep=2;
        ;;
esac    

if [ "$1" == "-n" ]; then
    sleep=$2
    shift; shift
fi


while :; 
    do 
    clear; 
    echo "$(date) every ${sleep}s $@"; echo 
    $@; 
    sleep $sleep; 
done

HTML5 Canvas background image

Make sure that in case your image is not in the dom, and you get it from local directory or server, you should wait for the image to load and just after that to draw it on the canvas.

something like that:

function drawBgImg() {
    let bgImg = new Image();
    bgImg.src = '/images/1.jpg';
    bgImg.onload = () => {
        gCtx.drawImage(bgImg, 0, 0, gElCanvas.width, gElCanvas.height);
    }
}

Android SharedPreferences in Fragment

Maybe this is helpfull to someone after few years. New way, on Androidx, of getting SharedPreferences() inside fragment is to implement into gradle dependencies

implementation "androidx.preference:preference:1.1.1"

and then, inside fragment call

SharedPreferences preferences;
preferences = androidx.preference.PreferenceManager.getDefaultSharedPreferences(getActivity());

Real-world examples of recursion

I wrote an XML parser once that would have been much harder to write without recursion.

I suppose you can always use a stack + iteration, but sometimes recursion is just so elegant.