一个蛮有用的event

add

event

Event object type: mx.events.FlexEvent
FlexEvent.type property = mx.events.FlexEvent.ADD

Dispatched when the component is added to a container as a content child by using the addChild() or addChildAt() method. If the component is added to the container as a noncontent child by using the rawChildren.addChild() or rawChildren.addChildAt() method, the event is not dispatched.

The FlexEvent.ADD constant defines the value of the type property of the event object for an add event.

当自己被添加到别的容器里面的时候所触发的事件  
经常我用到  
比如组件在换parent的时候 就晓得 他被加到哪个容器里面去了