flex加载外部swf文件，并且互相通讯

从网上转载的，还没时间鉴定，暂记录在这里
http://blog.csdn.net/zyjasp/archive/2008/05/16/2452175.aspx
第一步:建立加载类[CtmObjLoader],此类可以加载文件类型 [图片文件或swf文件]
package
{
import flash.display.DisplayObject;
import flash.display.Loader;
import flash.events.*;
import flash.net.URLRequest;
import mx.core.UIComponent;
public class CtmObjLoader extends UIComponent
{
  private var ProgressHandle:Function=null;
  public var loader:Loader;
  public var _bLoaded:Boolean=false;
  public var _bShow:Boolean=true;
  //@UrlRequest  加载的地址
  //@progressHandle 加载中的处理过程
  //bShow  加载后是否显示出来 
  public function CtmObjLoader(UrlRequest:String=null,progressHandle:Function=null,bShow:Boolean=true)
  {
   super();
   if(UrlRequest)LoadThis(UrlRequest,progressHandle,bShow);
  }
  public function LoadThis(UrlRequest:String,progressHandle:Function=null,bShow:Boolean=true):void{
   RemoveChild();
            loader = new Loader();
            _bShow=bShow;
            ProgressHandle=progressHandle;
            configureListeners(loader.contentLoaderInfo);
            if(_bShow)addChild(loader);//如果需要显示，则addchild
            var request:URLRequest = new URLRequest(UrlRequest);
            loader.load(request);   
  }
  public function UnLoadThis():void{
   try{
    RemoveChild();
    this.parent.removeChild(this);
   }catch(e:Err