AS3 Stage Align

Hi I just make a Switch to Flash CS3 and AS3 and one of my favorite tricks in AS2 are Stage Align for swf at fullscreen… and align my elements in the place I like

I just write some AS3 for Stage Align but doesn´t work

looks like this…

package {
   import flash.display.MovieClip;
   import flash.display.StageAlign;
   import flash.display.StageScaleMode;
  public class Test extends MovieClip {
      public function Test() {
         stage.align     = StageAlign.TOP_LEFT;
         stage.scaleMode = StageScaleMode.NO_SCALE;
	   public function onResize(event:Event)
          AppMain.x = stage.stageWidth / 2; 
          AppMain.y = stage.stageHeight / 2;

I see this thread and I want to do the same in AS3

Can anybody help me?