FLEX例子之树形菜单(Tree)

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical" verticalAlign="top"
    horizontalAlign="center" backgroundGradientColors="[0x000000,0x323232]" paddingTop="0" viewSourceURL="srcview/index.html">
 
    <mx:Script>
        <![CDATA[
 
            [Bindable]
            public var selectedNode:XML;
 
            // Event handler for the Tree control change event.
            public function treeChanged(event:Event):void {
                selectedNode=Tree(event.target).selectedItem as XML;
            }
        ]]>
    </mx:Script>
 
    <mx:XMLList id="treeData">
        <node label="Mail Box">
            <node label="Inbox">
                <node label="Marketing"/>
                <node label="Product Management"/>
                <node label="Personal"/>
            </node>
            <node label="Outbox">
                <node label="Professional"/>
                <node label="Personal"/>
            </node>
            <node label="Spam"/>
            <node label="Sent"/>
        </node> 
 
    </mx:XMLList>
 
    <mx:Panel title="Tree Control" layout="vertical" color="0xffffff" borderAlpha="0.15" width="500"
         paddingTop="10" paddingRight="10" paddingBottom="10" paddingLeft="10" horizontalAlign="center">
 
         <mx:Label width="100%" color="0x323232" 
            text="Select a node in the Tree control."/>
 
        <mx:HDividedBox width="100%" height="100%" color="0x323232">
            <mx:Tree id="myTree" width="50%" height="100%" labelField="@label"
                showRoot="false" dataProvider="{treeData}" change="treeChanged(event)"/>
            <mx:TextArea height="100%" width="50%"
                text="Selected Item: {selectedNode.@label}"/>
        </mx:HDividedBox>
 
    </mx:Panel>
</mx:Application>