jQuery.noConflict – Resolving conflicts with other javascript libraries that use $() function

One of the reasons that make a software popular is its extensions and plugins. jQuery has plenty of plugins that do almost anything you want, from simple button hide to full blown galleries. Plugins let non developers easily add functionality they need to their websites and there are times when one might include more than one javascript library such as prototype.js, YUI or mootools with jQuery. They all use $ as their main function name. Including second library might brake the behavior of the first one. To resolve such cases jQuery introduces .noConflict() method.

When you call .noConflict() jQuery will return $() to it’s previous owner and you will need to use jQuery() instead of shorthand $() function.

.noConflict() usage example (From jQuery Docs site)

  <script src="prototype.js"></script>
  <script src="jquery.js"></script>
    // Use jQuery via jQuery(...)
    // Use Prototype with $(...), etc.

You can also use the following code snippets to still use $() in your code, but with one drawback, you will not have access to your other library’s $() method.

// Method 1

// Method 2
(function($) {
    /* some code that uses $ */ 

Don’t forget that you can always assign jQuery to any other variable name to use it as your shorthand: var $_ = jQuery;

Identifying & locating mouse position in jQuery

While writing the next jQuery tutorial I needed to identify and locate where the mouse was on the page. Tracking mouse position on the page with jQuery is easy. You don’t need to check what browser the script is running like it is used to be with plain JavaScript. To identify where the mouse is in jQuery all you have to do is to read event object’s .pageX and .pageY properties.


   // e.pageX - gives you X position
   // e.pageY - gives you Y position

The above jQuery code is binding a new ‘on mouse move’ event to the current document and triggered every time mouse moves. The coordinates are calculated in pixels from top left corner of the document. See the above code in action.

You may also want to know the coordinates of the mouse relative to some <div> or an element. Since jQuery returns mouse position relative to the document root, by subtracting element’s position from document root you get mouse positions relative to that element. Long story short here is the code to do just that:

    var relativeX = e.pageX - this.offsetLeft;
    var relativeY = e.pageY - this.offsetTop;

Don’t forget that you can bind any mouse event to any element and then get mouse positions. You can easily create a draggable object with click and mousemove events by simply setting the CSS top and left values to .pageX and .pageY.

Anyway, that’s how you locate and handle mouse positions in jQuery. As always, you don’t need to worry about cross browser compatibility issues while using jQuery. To learn more see more examples here.