Flex：PopUpManager的createPopUp与addPopUp区别

 createPopUp:先设置好弹出方式，然后new出来一个TitleWindow的对象，再通过此对象设置它的表现形式。
addPopUp：先new出来对象，设置好表现形式，然后在选择弹出来。

要注意new对象与弹出方式的先后顺序！

<?xml version="1.0" encoding="utf-8"?>   
<!-- http://yecon.blog.hexun.com/29989820_d.html -->
<!-- http://www.slsay.com -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"  
        layout="vertical"  
        verticalAlign="middle"  
        backgroundColor="white"  
        creationComplete="init()">   
  
    <mx:Script>   
        <![CDATA[   
            import mx.managers.PopUpManagerChildList;   
            import mx.controls.Label;   
            import mx.events.CloseEvent;   
            import mx.containers.TitleWindow;   
            import mx.managers.PopUpManager;   
  
            private var titleWindow:TitleWindow;   
  
            private function init():void {   
                var label:Label = new Label();   
                label.text = "Hello world";   
                titleWindow = new TitleWindow();   
                titleWindow = TitleWindow(PopUpManager.createPopUp(this,TitleWindow,true));   
                titleWindow.title = "Custom title";   
                titleWindow.showCloseButton = true;   
                titleWindow.width = 240;   
                titleWindow.height = 180;   
                titleWindow.addChild(label);   
                titleWindow.addEventListener(CloseEvent.CLOSE, titleWindow_close);   
                               PopUpManager.centerPopUp(titleWindow);   
            }   
  
            private function titleWindow_close(evt:CloseEvent):void {   
                PopUpManager.removePopUp(titleWindow);   
            }   
        ]]>   
    </mx:Script>   
  
    <mx:Button label="Launch TitleWindow" click="init()" />   
  
</mx:Application>
 

-----------------------------------------------------------------

<?xml version="1.0" encoding="utf-8"?>   
<!-- http://yecon.blog.hexun.com/29989820_d.html -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"  
        layout="vertical"  
        verticalAlign="middle"  
        backgroundColor="white"  
        creationComplete="init()">   
  
    <mx:Script>   
        <![CDATA[   
            import mx.controls.Label;   
            import mx.events.CloseEvent;   
            import mx.containers.TitleWindow;   
            import mx.managers.PopUpManager;   
  
            private var titleWindow:TitleWindow;   
  
            private function init():void {   
                var label:Label = new Label();   
                label.text = "Hello world";   
  
                titleWindow = new TitleWindow();   
                titleWindow.title = "Custom title";   
                titleWindow.showCloseButton = true;   
                titleWindow.width = 240;   
                titleWindow.height = 180;   
                titleWindow.addEventListener(CloseEvent.CLOSE, titleWindow_close);   
                titleWindow.addChild(label);   
  
                PopUpManager.addPopUp(titleWindow, this, true);   
                PopUpManager.centerPopUp(titleWindow);   
            }   
  
            private function titleWindow_close(evt:CloseEvent):void {   
                PopUpManager.removePopUp(titleWindow);   
            }   
        ]]>   
    </mx:Script>   
  
    <mx:Button label="Launch TitleWindow" click="init()" />   
  
</mx:Application>