Flex之旅：第二部分：容器与布局(5)---如何管理多个弹出的页面

想要管理多个弹出的页面，就得获得这些页面的id引用。虽然PopUpManager.addPopUp可以创建弹出页面，但是这个方法没有返回值。

幸好，PopUpManager.createPopUp方法有返回值，返回的就是当前弹出的页面对象。

如果有很多弹出页面，那么就用Array去存储每个弹出页面的对象，以方便将来的使用，

示例 代码如下：

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
         xmlns:s="library://ns.adobe.com/flex/spark"
         xmlns:mx="library://ns.adobe.com/flex/mx"
         minWidth="955" minHeight="600" creationComplete="addDialog()">
  <fx:Script>
    <![CDATA[
      import mx.managers.PopUpManagerChildList;
      import mx.controls.LinkButton;
      import mx.containers.Panel;
      import mx.managers.PopUpManager;
      
      public var popUpArray:Array = new Array();
      
      private function addDialog():void
      {
        var pop:Panel = (PopUpManager.createPopUp(this, mx.containers.Panel, false, PopUpManagerChildList.POPUP) as Panel);
        pop.title = "First Pop Up";
        pop.y = 100;
        popUpArray.push(pop);
        pop = (PopUpManager.createPopUp(this, mx.containers.Panel, false, PopUpManagerChildList.POPUP) as Panel);
        pop.title = "Second Pop Up";
        pop.y = 200;
        popUpArray.push(pop);
        pop = (PopUpManager.createPopUp(this, mx.containers.Panel, false, PopUpManagerChildList.POPUP) as Panel);
        pop.title = "Third Pop Up";
        pop.y = 300;
        popUpArray.push(pop);
      }
      
      private function returnDialog():void
      {
        var link:LinkButton = new LinkButton();
        link.label = "Hello";
        (popUpArray[selectDialog.selectedIndex] as
          Panel).addChild(link);
      }
    ]]>
  </fx:Script>
<mx:HBox>
  
  <mx:ComboBox id="selectDialog" change="returnDialog()">
    <mx:dataProvider>
      <fx:Array>
        <fx:Number>0</fx:Number>
        <fx:Number>1</fx:Number>
        <fx:Number>2</fx:Number>
      </fx:Array>
    </mx:dataProvider>
  </mx:ComboBox>
  <mx:Panel>
    <mx:LinkButton label="Button"/>
  </mx:Panel>
  <mx:Panel>
    <mx:LinkButton label="Button"/>
  </mx:Panel>
</mx:HBox>
  
</s:Application>