Flex 弹出层 事件

JScript code:
<mx:XML source="bookscatalog.xml" id="xmlData"/> 先用XML数据源
<mx:Panel width="540">
<mx:VBox>
<comp:Product id="ps" xmlData="{xmlData}"></comp:ProductSlider>
</mx:VBox>
</mx:Panel>

prodcut.mxml:
[Bindable]
public var xmlData:XML;
[Bindable]
public var cartData:ArrayCollection;
private function init():void{
horizontalList.addEventListener(CartEvent.ADD_TO_CART,addToCartHandler);注册一个事件
cartData=new ArrayCollection();
}

private function displayDetails():void{
var popup:View=new View();
popup.book=XML(horizontalList.selectedItem);
PopUpManager.addPopUp(popup,parent.parent,true);
PopUpManager.centerPopUp(popup);
弹出的View里有一个按钮,如何把添加事件执行完在这个CartData得到变化,然后显示在DataGrid里面呢?如果不是弹出的层是可以的.在init()里会有事件监听,弹出的就不行了.
}

private function myScroll(event:ScrollEvent):void{
horizontalList.horizontalScrollPosition=event.position;
}
private function addToCartHandler(evt:CartEvent):void{
Alert.show("productSlider:"+XML(evt.bookObj)); 这句始终没有执行.
ca