as3.0加载图片，设置不失真

package com{
    import flash.display.MovieClip;
    import flash.net.URLRequest;
    import flash.display.Loader;
    import flash.events.MouseEvent;
    import flash.events.Event;
    import flash.display.SimpleButton;
    import flash.display.Bitmap;

    public class LoaderJPG extends MovieClip {

        public static var urlR:URLRequest;
        public static var loader:Loader;
        public static var emptyMc:MovieClip;
        public static var thisMc:MovieClip;
        public function LoaderJPG(_thisMc:MovieClip,_emptyMc:MovieClip) {
            emptyMc = _emptyMc;
            thisMc = _thisMc;
            urlR= new URLRequest();
        }

        public static function addJPG(jpgName:String) {
            loader=new Loader();
            urlR.url = "JPG/"+jpgName + ".png";
            loader.load(urlR);
            loader.contentLoaderInfo.addEventListener(Event.COMPLETE, completeFun);
        }
        public static function completeFun(e:Event) {
            //emptyMc.addChildAt(loader,emptyMc.numChildren);
            emptyMc.addChildAt(new Bitmap(e.target.loader.content["bitmapData"],"auto",true),emptyMc.numChildren);
            
            
            if (emptyMc.numChildren >= 2) {
                emptyMc.removeChildAt(0);
            }
            //trace(emptyMc.numChildren);
        }
    }

}