下面演示了一个鼠标拖动元件的样例，同时该元件拖动范围只限在父容器内部

protected function init(event:FlexEvent):void
{
    cav.addEventListener(MouseEvent.MOUSE_DOWN, itemMouseDown);
    cav.addEventListener(MouseEvent.MOUSE_UP, itemMouseUp);
}
 
private function itemMouseDown(event:MouseEvent):void{
    var width:int = cav.parent.width - cav.width;
    var height:int = cav.parent.height - cav.height; 
    cav.startDrag(false, new Rectangle(0, 0 , width, height));
}
 
private function itemMouseUp(event:MouseEvent):void{
    cav.stopDrag();
}