[jQuery Plugin] imagesLoaded偵測圖檔已被讀取

需要偵測圖檔已被讀取完畢的話，可以使用imagesLoaded這個外掛:)

// $('img.photo',this).imagesLoaded(myFunction)
// execute a callback when all images have loaded.
// needed because .load() doesn't work on cached images

// mit license. paul irish. 2010.
// webkit fix from Oren Solomianik. thx!

// callback function is passed the last image to load
//   as an argument, and the collection as `this`


$.fn.imagesLoaded = function(callback){
  var elems = this.filter('img'),
      len   = elems.length,
      blank = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///ywAAAAAAQABAAACAUwAOw==";
      
  elems.bind('load.imgloaded',function(){
      if (--len <= 0 && this.src !== blank){ 
        elems.unbind('load.imgloaded');
        callback.call(elems,this); 
      }
  }).each(function(){
     // cached images don't fire load sometimes, so we reset src.
     if (this.complete || this.complete === undefined){
        var src = this.src;
        // webkit hack from http://groups.google.com/group/jquery-dev/browse_thread/thread/eee6ab7b2da50e1f
        // data uri bypasses webkit log warning (thx doug jones)
        this.src = blank;
        this.src = src;
     }  
  }); 

  return this;
};