Flex中通过isPopUp属性创建一个不可拖动TitleWindow的例子
main.mxml

<?xml version="1.0" encoding="utf-8"?><mx:Application name="PopUpManager_TitleWindow_isPopUp_test"        xmlns:mx="http://www.adobe.com/2006/mxml"        layout="vertical"        verticalAlign="middle"        backgroundColor="white">    <mx:Script>        <![CDATA[            import mx.containers.TitleWindow;            import mx.managers.PopUpManager;            private var titleWin:MyTitleWin;            private function launch():void {                titleWin = PopUpManager.createPopUp(this, MyTitleWin, true) as MyTitleWin;                PopUpManager.centerPopUp(titleWin);            }        ]]>    </mx:Script>    <mx:ApplicationControlBar dock="true">        <mx:Button id="btn"                label="Launch TitleWindow PopUp"                click="launch();" />    </mx:ApplicationControlBar></mx:Application>

MyTitleWin.mxml

 <?xml version="1.0" encoding="utf-8"?> <mx:TitleWindow xmlns:mx="http://www.adobe.com/2006/mxml"        layout="absolute"        showCloseButton="true"        title="TitleWindow"        width="300"        height="200"        close="titleWin_close(event);">    <mx:Script>        <![CDATA[            import mx.core.IFlexDisplayObject;            import mx.events.CloseEvent;            import mx.managers.PopUpManager;            private function titleWin_close(evt:CloseEvent):void {                PopUpManager.removePopUp(evt.target as IFlexDisplayObject);            }            private function checkBox_change(evt:Event):void {               [color=red] this.isPopUp[/color] = checkBox.selected;            }        ]]>    </mx:Script>    <mx:Label text="Drag this window"            horizontalCenter="0"            verticalCenter="0" />    <mx:ControlBar>        <mx:CheckBox id="checkBox"                label="isPopUp:"                labelPlacement="left"                selected="true"                change="checkBox_change(event);" />    </mx:ControlBar> </mx:TitleWindow>

解释：
public static function createPopUp(parent:DisplayObject, className:Class, modal:Boolean = false, childList:String = null, moduleFactory:IFlexModuleFactory = null):IFlexDisplayObject
参数
1、parent:DisplayObject — DisplayObject，用于确定要使用 SystemManager 的哪些层，以及（可选）确定居中新的顶级窗口所用的参考点。它可能并非弹出窗口的实际父项，因为所有弹出窗口都以 SystemManager 为父项。

2、className:Class — 要为弹出窗口创建的对象的类。该类必须实现 IFlexDisplayObject。

3、modal:Boolean (default = false) — 如果为 true，则该窗口为模态窗口，也就是说在删除该窗口之前，用户将无法与其他弹出窗口交互。

4、childList:String (default = null) — 要将弹出窗口添加到的子项列表。PopUpManagerChildList.APPLICATION、PopUpManagerChildList.POPUP 或 PopUpManagerChildList.PARENT（默认）中的任意一项。

5、moduleFactory:IFlexModuleFactory (default = null) — 此弹出窗口应在其中查找其嵌入字体和样式管理器的 moduleFactory。