private function init():void
    {
     stage.align = StageAlign.TOP_LEFT;
     stage.scaleMode = StageScaleMode.NO_SCALE;
     box = new Sprite();
     box.graphics.beginFill(0xff0000);
     box.graphics.drawRect(-50, -50, 100, 100);
     box.graphics.endFill();
     addChild(box);
     addEventListener(Event.ENTER_FRAME, onEnterFrame);
    }