Evt handler loading swf in mc on timeline, error 1119

1

Hello Everybody

I am going in circles with loading an external swf into a movieclip on the timeline and need help urgently.

There is a hotspot movieclip which is linked to following class:

package {

  import flash.display.MovieClip;
  import flash.events.*;
  import flash.net.URLRequest;
  import flash.display.DisplayObject;
  import flash.display.Loader;
  import Picture_Container;
  
  
  public class HotSpot1 extends MovieClip{
        var reqName:String;
        var target:DisplayObject;
              
        function HotSpot1():void{
              this.addEventListener(MouseEvent.CLICK, PictureCall);
              this.buttonMode = true;
        }
  
        public function PictureCall(event:MouseEvent):void{
              reqName = this.name + ".swf";
              trace(reqName);
              trace(this.parent.name);
              target = this.parent.getChildByName("picture_container");
              trace(target);
              trace(target.name);
              trace(this.parent.getChildIndex(target));
              trace(target.parent.name);
              
              var req:URLRequest = new URLRequest(reqName);
              var loader:Loader = new Loader();
              loader.load(req);
              //this.parent.picture_container.addChild(loader);
        }
  }

}

the .addChild(loader) code is the problem, therefore commented out. All the traces work perfectly and when clicking on the instance Page_01 of the hotspot movieclip I get following output:

Page_01.swf
Gallery_Background
[object Picture_Container]
picture_container
103
Gallery_Background

However, if I activate the addChild line it throws following error:

1119: Access of possibly undefined property picture_container through a reference with static type flash.display:DisplayObjectContainer.

The movieclip which should load the swf is linked to the class:

package {

  import flash.display.MovieClip;
  import HotSpot1;
  
  public class Picture_Container extends MovieClip{
        
        function Picture_Container():void{
              trace(this.parent.name);
              trace(this.name);
        }
  }

}

the traces work and the output shows:

Gallery_Background
picture_container

Thanks to all of you for giving it your thoughts