使用一个Loaderload资源时报错误

的解决方案

package com.asdia.comptest
{
 import flash.display.Bitmap;
 import flash.display.Loader;
 import flash.display.Sprite;
 import flash.events.Event;
 import flash.net.URLRequest;
 import flash.system.System;
 public class DisplayTesting extends Sprite
 {
  public var text:String ;
  private static var _loader:Loader= null;
  public function DisplayTesting()
  {
  

  }
  public function LoadImg():void{
   //_loader=new Loader();
   _loader=getLoaderIntance();
   _loader.contentLoaderInfo.addEventListener(Event.COMPLETE,showImg)
   if(_loader.content!=null){
    
    _loader.removeEventListener(Event.COMPLETE,showImg);
    _loader=null;
    _loader=getLoaderIntance();
   }
   
   _loader.contentLoaderInfo.addEventListener(Event.COMPLETE,showImg)
   _loader.load(new URLRequest("http://images.sohu.com/uiue/sohu_logo/beijing2008/2008sohu.gif"));
  }
  static public function  getLoaderIntance():Loader{
   if(_loader==null){
    _loader=new Loader();
    return _loader;
   }else{
    return _loader;
   }
  }
  private function showImg(event:Event):void{
   var image:Bitmap=_loader.contentLoaderInfo.content as Bitmap;
   
   this.addChild(image);
   trace(System.totalMemory);
  }
  
 }

}