How to use with Cookies in Javascript.

function createCookie(name,value,days) {
if (days) {
var date = new Date();
date.setTime(date.getTime()+(days*24*60*60*1000));
var expires = "; expires="+date.toGMTString();
}
else var expires = "";
document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
var nameEQ = name + "=";
var ca = document.cookie.split(';');
for(var i=0;i < ca.length;i++) {
var c = ca[i];
while (c.charAt(0)==' ') c = c.substring(1,c.length);
if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
}
return null;
}

function eraseCookie(name) {
createCookie(name,"",-1);
}

 createCookie("username","rkumar670","30");
var val = readCookie("username");
output = rkumar670


eraseCookie('rkumar670');

LocalStorage

LocalStorage works mostly as you expect it; it’s a simple key-value-store with a finite amount of storage, and once you hit that you get an exception. But we got a really wierd bug report from a user where he would browse to another site, and come back to the application to find that all of his settings and data were gone.

Turns out that under some circumstances, Android doesn’t load the localStorage data when you hit the back button. I’m guessing it has something to do with the fact that Android doesn’t always reload the page when you go back, it loads it from the browser cache (not the application cache) instead.

So to get around this Android bug, we set a persistent value in localStorage which we use as a check to see if localStorage is correctly loaded.


var check = "1234567890"
localStorage.setItem("android_check", check);

and when we want to fetch something from localStorage, we do:

var hasItem = function() {
  return (typeof localStorage[key] != "undefined" && localStorage[key] !== null);
}


var getItem = function(key, def) {
  if (!hasItem(key)) {
    if (localStorage.getItem("android_check") !== check) {
      // Reload the page so Android reloads localStorage
      window.location.reload();
    }
    return def;
  }
  return localStorage.getItem(key);
}

Gmail Tip: Mark All Unread Mail as Read

I Have thousand of unread mails. it is time consuming to make all mails to read.
1.Go to your Settings/Filters page and create a new filter.
2. In the Has the words field enter “is:unread” (without quotes), and click the Next Step button
3.You’ll get a message warning you that this type of filter won’t be applied to new mail, but that’s OK. Click OK to continue.
4.Check the boxes next to Mark as read and Also apply filter to … conversations below.
5.Click Create Filter button, and you’re done. You might want to should delete the filter once you finish since it won’t be needing it anymore.

PhoneGap Android XhrFileReader

This post is copy from the simon macdonst blog this help me a lot in my one of the app.

The FileReader API works great as long as the file you want to read is on the device's file system. However if you want to read a file you've packed in the Android assets folder you would need to use XHR to read the file. I'm providing an interface that follows the same API as the regular FileReader. Of course the XhrFileReader is not limited to only reading files from the assets folder, it can also read files from the file system and over HTTP.

Adding the plugin to your project 

To install the plugin, move XhrFileReader.js to your project's www folder and include a reference to it in your html files.

Using the plugin 

To instantiate a new reader use the folling code:

var reader = cordova.require("cordova/plugin/xhrfilereader"); 

Setup your event handlers:

// called once the reader begins
reader.onloadstart = function() {
    console.log("load start");
};
// called when the file has been completely read
reader.onloadend = function(evt) {
    console.log("File read");
    console.log(evt.target.result);
}; 

Unfortunately, you will only get an error on files read over HTTP. When you specify a file:// path the request status is always 0. There is no way to tell between a successful read or an error. So if you specify a file that does not exist like "file:///does.not.exist.txt" you will get an empty evt.target.result in your onloadend handler.

// called if the reader encounters an error
reader.onerror = function(error) {
    console.log("Error: " + error.code);
}; 

Progress events are fired but are not very useful as they don't contain partial results.

// called while the file is being read
reader.onprogress = function(evt) {
    console.log("progress");
}; 

Finally call your read method, for instance:

reader.readAsText("http://www.google.com"); reader.readAsText("file:///android_asset/www/config.json"); reader.readAsText("file:///sdcard/error.log");

and that's about it. Obviously, this plugin is most useful when you need to read a text file from the assets folder.

Github: https://github.com/macdonst/XhrFileReader

How can I add older version of iOS SDK in Xcode

I create a Iphone app is working fine in the iOS 5.1 sdk but now in iOS 6.1 sdk.  Then i update my Xcode to 4.6.1 now what happen i sort out  the app issue but when i am trying to submit the app was trying to build the ipa file it gave an error

Apple Mach-o linker error

 linker command failed with exit code 1 (use -v to see invocation)

Here is my solution note.

1. Download xcode_4.4.1_6938145.dmg in https://developer.apple.com/downloads/
2. Load up the dmg file then go to Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/ you will find iPhoneOS5.1.sdk (this is what i want in this case).
3. Copy iPhoneOS5.1.sdk folder into your Xcode folder /Applications/Xcode/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs
4. Restart Xcode
5. Open Xcode project setting->build settings->base SDK, then you will see iOS 5.1 option.

You need to copy the iPhoneOS5.1.sdk to the directory

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.1.sdk

and iPhoneSimulator5.1.sdk to

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.1.sdk

Now restart your Xcode change the iOS to 6.1 to 5.1 THen it will compile the app into your iPhone. if it is helpful then post a comment below.

what is the shortcut key in eclipse? ( Eclipse Shortcuts)

Essential Shortcuts

The list of shortcuts in Eclipse is fairly long yet readily available. In fact starting with Eclipse 3.1 the full list of shortcuts can be displayed from anywhere via Ctrl+Shift+L. Nevertheless, call it information fatigue or simply a matter of style, deserving shortcuts frequently remain overlooked.

Below is a list of those shortcuts I find essential. What I mean by that is if you don't use them then you probably need additional time to execute essential everyday tasks and are not very comfortable navigating around.

So without further ado here is the list: 

Ctrl+Shift+T	Find Java Type	Start typing the name and the list gets smaller. Try typing the capital letters of the class only (e.g. type "CME" to find "ConcurrentModificationException")
Ctrl+Shift+R	Find Resource	Use this to look for XML files, text files, or files of any other type. which are in your workspace.
Ctrl+E	Open Editor Drop-Down	Presents a popup window listing currently opened files. Start typing to limit the list or simply use the down arrow key.
Ctrl+O	Quick Outline	Use this to find a method or a member variable in a class. Start typing to limit the choices. Press Ctrl+O a second time to include inherited methods.
Ctrl+Space	Content Assist	Context sensitive content completion suggestions while editing Java code.
Ctrl+Shift+Space	Context Information	If typing a method call with several parameters use this to show the applicable parameter types. The current parameter where the cursor is will be shown in bold.
Ctrl+Shift+O	Organize Imports	After typing a class name use this shortcut to insert an import statement. This works if multiple class names haven't been imported too.
F3	Open Declaration	Drills down to the declaration of the type, method, or variable the cursor is on. This works much like a browser hyperlink.
Alt+Left	Backward History	This works like a browser's Back button.
Alt+Right	Forward History	This works like a browser's Forward button
Ctrl+L	Go to Line	Go to a specific line number.
F4	Open Type Hierarchy	Show the type hierarchy (downward tree) or the supertype hierarchy (upward tree).
Ctrl+Alt+H Ctrl+Shift+F	Open Call Hierarchy	Show where a method is called from. In the Call Hierarchy view keep expanding the tree to continue tracing the call chain. Auto align the code
Alt+Shift+Up Alt+Shift+Down Alt+Shift+Left Alt+Shift+Right Select Enclosing Element Restore Last Selection Select Previous Element Select Next Element Useful for selecting context-sensitive blocks (e.g. surrounding loop, method, class, etc.) Ctrl+Up Ctrl+Down Scroll Line Up Scroll Line Down Very handy if you want to scroll by 1 line without changing your cursor position or using the mouse. Ctrl+Shift+Up Ctrl+Shift+Down Go to Previous Member Go to Next Member Great for stepping down through the methods of a Java source file. Ctrl+Shift+U Alt+Shift+U Show Occurrences in File Remove Occurrences Annotations Use this to search within the same file - useful for occurrences of private fields and methods. Ctrl+Shift+P Go to Matching Bracket Helps to find the closing bracket of lengthly if-else statements. Ctrl+J Ctrl+Shift+J Incremental Find Reverse Incremental Find The first matching occurrence is shown with each typed letter. Press again and the next matching occurrence is shown. Shift+Enter Ctrl+Shift+Enter Insert Line Below Insert Line Above Insert a line above or below the current line. Ctrl+/ Ctrl+\ Add Block Comment Remove Block Comment Comment in/out blocks of code with a key stroke. Ctrl+M Maximize Active View or Editor Maximize the current view or editor at the expense of all other currently shown views. Press again to restore to normal view. Ctrl+F6 Ctrl+F7 Ctrl+F8 Next Editor Next View Next Perspective Learn these to switch among edited files, open views and perspectives. Ctrl+Alt+Up Ctrl+Alt+Down Duplicate Lines Copy Lines Doesn't seem like it at first but a great shortcut once you learn to use it. Instead of select, copy and paste simply select and duplicate without affecting the clipboard. Alt+/ Word Completion This is excellent for code editing or writing plain help files with variables and other words having no English language equivalents. The word completion is based on the set of words already present in the current file. Ctrl+I Correct Indentation Select a block of Java code or an entire class file and use this shortcut to correct its indentation. Shift Tab Tab Remove Tab Add Tab Select one or more lines of code and use this shortcut to intent them further/less. Ctrl+H	Open Search Dialog	Opens a search dialog with extensive search options for Java packages, types, methods, and fields.
Alt+Shift+R	Rename - Refactoring	Use this to rename type, method, or field. All existing references will be refactored as well.
Alt+Shift+L	Extract Local Variable	Use this to create a local variable from the selected expression. This is useful for breaking up larger expressions to avoid long lines.
Alt+Shift+M	Extract Method	Use this to extract a new method from existing code. The parameter list and return type will be automatically created.

Trying Out Shortcuts

A few things to keep in mind as you try the above shortcuts. If a shortcut doesn't have the described effect check if one of these is the cause of your problem:

·         Do you have an older version of Eclipse? Check the Help section to confirm the shortcut is available.

·         Is the shortcut applicable to the context (perspective) you're in? For example Ctrl+Shift+T (Open Type) is applicable in the Java perspective but not in the Resource perspective. You can find out where each shortcut is applicable by pressing Ctrl+Shift+L or by checking the Help section.

·         Is the shortcut already taken by another application? If so the other application will probably come to the foreground when you use the shortcut.

·         Is the shortcut defined twice in Eclipse? This can happen on occasion if you install additional plugins with overlapping shortcuts or more likely if you've tried to map shortcuts of your own. If there is conflict the shortcut won't work. To check this go to the Preferences or press Ctrl+Shift+L twice.

How to call .ashx file through jquery

your aspx page.
add the latest jquery into the head section

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js" type="text/javascript"></script>

<script>
//document ready
$(function(){
$.ajax({
            type: "POST",
            url: "handler.ashx",
            data: { firstName: 'Rahul', lastName: 'Kumar' },
            // DO NOT SET CONTENT TYPE to json
            // contentType: "application/json; charset=utf-8",
            // DataType needs to stay, otherwise the response object
            // will be treated as a single string
            dataType: "json",
            success: function (response) {
                alert(response.d);
            }
        });
});
</script>

your handler.ashx file

    using System;
    using System.Web;
    using Newtonsoft.Json;

    public class Handler : IHttpHandler
    {
        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";

            string myName = context.Request.Form["firstName"];

            // simulate Microsoft XSS protection
            var wrapper = new { d = myName };
            // in order to use JsonConvert you have to download the
            // Newtonsoft.Json dll from here  http://json.codeplex.com/
            context.Response.Write(JsonConvert.SerializeObject(wrapper));
        }

        public bool IsReusable
        {
           get
           {
                return false;
           }
        }
    }

Things you may not know about jQuery.

Do you have a tip nobody knows about? – Add it in the comments…

• $.fn is just a shortcut to jQuery.prototype.
• You can test if a jQuery collection contains any elements by trying to access the first element, e.g. if($(selector)[0]){...}.
• jQuery normalizes the event object across all browsers! Have a look at all the available properties/methods over here: http://docs.jquery.com/Events/jQuery.Event.
• When you create a plugin you have access to the jQuery chain’s previous object:

  jQuery.fn.doSomething = function() {
      this; // => $('a')
      this.prevObject; // => $('li')
      // Remember chaining in your plugins:
      return this;
  };
   
  jQuery('li').show()
      .find('a').doSomething();
   
  // You could even create a new 'root' plugin:
  // (Returns the 'root' of a chain)
  jQuery.fn.root = function() {
      // Root is always document so we have to 
      // go back to one before the last:
      var root = this;
      while(root.prevObject.prevObject) {
          root = root.prevObject;
      }
      return root;
  };
   
  $('li').find('a').children().root(); // <= $('li') is returned
  // Using root() is the same as using end().end() in this situation

• You can namespace events! This is especially useful for plugin development:

  jQuery.fn.myPlugin = function() {
   
      // Clean up after yourself!
   
      jQuery.myPlugin = {
          cleanUp: function() {
   
              // Remove all click handlers binded
              // as a result of the plugin:
              jQuery('*').unbind('click.myPlugin');
   
              // ALternatively, remove ALL events:
              jQuery('*').unbind('.myPlugin');
   
          }
      };
   
      return this.bind('click.myPlugin', function() {
          // Do something...
      });
  };
   
  // Note, you can also namespace data:
  // E.g. $(elem).data('whatever.myPlugin',value);

• You can access all event handlers bound to an element (or any object) through jQuery’s event storage:

  // List bound events:
  console.dir( jQuery('#elem').data('events') );
   
  // Log ALL handlers for ALL events:
  jQuery.each($('#elem').data('events'), function(i, event){
      jQuery.each(event, function(i, handler){
          console.log( handler.toString() );
      });
  });
   
  // You can see the actual functions which will occur
  // on certain events; great for debugging!

• jQuery natively supports JSONP (‘JSON with padding’) which effectively means you can make cross-domain "Ajax" requests (although not strictly Ajax since it doesn’t use XHR). For this to work the requested domain must have some JSONP API in place (it must be able wrap the JSON with a specified callback function). An example:

  function getLatestFlickrPics(tag,callback) {
      var flickrFeed = 'http://api.flickr.com/services/feeds/photos_public.gne?tags='
                     + tag + '&tagmode=any&format=json&jsoncallback=?';
      jQuery.getJSON(flickrFeed, callback);
  }
   
  // Usage:
  getLatestFlickrPics('ferrari', function(data){
      jQuery.each(data.items, function(i, item){
          $("<img/>").attr("src", item.media.m).appendTo('body');
      });
  });

• You might find it a little messy but jQuery enables us to create an entire DOM structure within a single chain:

  // Create and inject in one chain:
  jQuery('<div/>')
      .append('<p><a href="#">Foo</a></p>')
      .find('p a')
          .click(function(){
              // Do something...
              return false;
          })
          .end()
      .append('<p><a href="#">Bar</a></p>')
      .find('p:eq(1) a')
          .click(function(){
              // Do something else...
              return false;
          })
          .end()
      .appendTo('body');

• Accessing the DOM elements within a jQuery collection is incredibly easy:

  var HTMLCollection = $('div').get();
   
  // Alternatively, if you only want the first element:
  $('div').get(0);
  $('div').get()[0];
  $('div')[0];

• Not only can you bind events to DOM elements; you can also bind a custom event to ANY object!

  function Widget() {
      // Do something...
  };
   
  var myPhotoWidget = new Widget('photos');
   
  jQuery(myPhotoWidget).bind('photoAdd', function() {
      // Custom event handling...
  });
   
  // Trigger event:
  jQuery(myPhotoWidget).trigger('photoAdd');

• Finding the index of a selected element is very easy. jQuery gives us the ‘index’ method:

  $('table tr').click(function(){
      // Find index of clicked table row:
      var index = $('table tr').index(this);
  });

• You can create your own filter selectors. I did a post on this a while back, but take a look at an example anyway:

  $.expr[':'].external = function(elem,index,match) {
      var url = elem.href || elem.src,
          loc = window.location;
      return !!url.match(new RegExp('^' + loc.protocol + '//' + '(?!' + loc.hostname + ')' ));
  };
   
  // You can now use it within your selectors:
   
  // Find all external anchors:
  $('a:external');
   
  // Find all external script elements:
  $('script:external');
   
  // Determine if link is external:
  $('a#mylink').is(':external'); // true/false

• I see quite a lot of people still using JavaScript’s FOR or WHILE constructs to create loops in their jQuery scripts. There’s nothing wrong with this but be aware that jQuery’s ‘each’ method can also iterate over arrays and objects!

  var myArr = ['apple','banana','orange'];
   
  $.each(myArr, function(index, item) {
      // Do something with 'item'
      // return false to BREAK
      // return true to CONTINUE
  });

• The ‘filter’ method accepts a String selector or a function. When using it with a function you must return false to remove the element from the stack and true to keep it:

  $('div').filter(function(){
      return this.childNodes.length > 10; // Must return a Boolean
  });

• You don’t have to give new elements IDs or classes to reference them later, just cache them into a variable:

  var myInjectedDiv = $('<div/>').appendTo('body');
   
  // Use 'myInjectedDiv' to reference the element:
  myInjectedDiv.bind('click', function(){
      // ...
  });

• jQuery’s ‘map’ method is incredibly useful, the passed function will be run on every item of the passed array (or object) and whatever the function returns each time is added to the new array, take a look:

  // Create an array containing all anchor HREF attributes:
  var URLs = $.map($('a'), function(elem, index){
      return elem.href;
  });
   
  // URLs = ['http://google.com', 'http://whatever.com', 'http://yahoo.com']

• This isn’t jQuery related but it can be very useful. When you need to compare two different ways of doing something (performance-wise) you can use the Firebug console to log the time taken to complete a chunk of code, for example:

  console.time('My first method');
  // Do something...
  console.timeEnd('My first method');
   
  console.time('My second method');
  // Do something else...
  console.timeEnd('My second method');
   
  // Firebug will log the time (in milliseconds) taken
  // to complete each chunk...