Flex中如何通过showCloseButton属性，控制TitleWindow右上角关闭按钮有效/无效

 main.mxml

1. <?xml version="1.0" encoding="utf-8"?>
2. <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
3.         layout="horizontal"
4.         verticalAlign="middle"
5.         backgroundColor="white">
6.  
7.     <mx:TitleWindow id="titleWindow1"
8.             showCloseButton="true"
9.             title="TitleWindow"
10.             status="showCloseButton = true"
11.             width="50%"
12.             height="100%" />
13.  
14.     <mx:TitleWindow id="titleWindow2"
15.             showCloseButton="false"
16.             title="TitleWindow"
17.             status="showCloseButton = false"
18.             width="50%"
19.             height="100%" />
20.  
21. </mx:Application>