1 /*! Copyright (c) 2010 Brandon Aaron (http://brandonaaron.net)
  2  * Licensed under the MIT License (LICENSE.txt).
  3  *
  4  * Thanks to: http://adomas.org/javascript-mouse-wheel/ for some pointers.
  5  * Thanks to: Mathias Bank(http://www.mathias-bank.de) for a scope bug fix.
  6  * Thanks to: Seamus Leahy for adding deltaX and deltaY
  7  *
  8  * Version: 3.0.4
  9  * 
 10  * Requires: 1.2.2+
 11  */
 12 
 13 (function($) {
 14 
 15 var types = ['DOMMouseScroll', 'mousewheel'];
 16 
 17 $.event.special.mousewheel = {
 18     setup: function() {
 19         if ( this.addEventListener ) {
 20             for ( var i=types.length; i; ) {
 21                 this.addEventListener( types[--i], handler, false );
 22             }
 23         } else {
 24             this.onmousewheel = handler;
 25         }
 26     },
 27     
 28     teardown: function() {
 29         if ( this.removeEventListener ) {
 30             for ( var i=types.length; i; ) {
 31                 this.removeEventListener( types[--i], handler, false );
 32             }
 33         } else {
 34             this.onmousewheel = null;
 35         }
 36     }
 37 };
 38 
 39 $.fn.extend({
 40     mousewheel: function(fn) {
 41         return fn ? this.bind("mousewheel", fn) : this.trigger("mousewheel");
 42     },
 43     
 44     unmousewheel: function(fn) {
 45         return this.unbind("mousewheel", fn);
 46     }
 47 });
 48 
 49 
 50 function handler(event) {
 51     var orgEvent = event || window.event, args = [].slice.call( arguments, 1 ), delta = 0, returnValue = true, deltaX = 0, deltaY = 0;
 52     event = $.event.fix(orgEvent);
 53     event.type = "mousewheel";
 54     
 55     // Old school scrollwheel delta
 56     if ( event.wheelDelta ) { delta = event.wheelDelta/120; }
 57     if ( event.detail     ) { delta = -event.detail/3; }
 58     
 59     // New school multidimensional scroll (touchpads) deltas
 60     deltaY = delta;
 61     
 62     // Gecko
 63     if ( orgEvent.axis !== undefined && orgEvent.axis === orgEvent.HORIZONTAL_AXIS ) {
 64         deltaY = 0;
 65         deltaX = -1*delta;
 66     }
 67     
 68     // Webkit
 69     if ( orgEvent.wheelDeltaY !== undefined ) { deltaY = orgEvent.wheelDeltaY/120; }
 70     if ( orgEvent.wheelDeltaX !== undefined ) { deltaX = -1*orgEvent.wheelDeltaX/120; }
 71     
 72     // Add event and delta to the front of the arguments
 73     args.unshift(event, delta, deltaX, deltaY);
 74     
 75     return $.event.handle.apply(this, args);
 76 }
 77 
 78 })(jQuery);