tree.mxml

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white" width="226" height="673">
   <mx:Script>
        <![CDATA[
            import mx.events.ListEvent;

            private function tree_itemClick(evt:ListEvent):void {
              
                var t:Tree = evt.currentTarget as Tree;
                var dataObj:Object = evt.itemRenderer.data;
                if (dataObj.hasOwnProperty("@src")) {
                 //test.text=dataObj.@src;
                 navigateToURL(new URLRequest(dataObj.@src),"mainFrame");  //mainFrame为右框架名称
                }
                 else if (t.dataDescriptor.isBranch(t.selectedItem)) {
                 //   test.text="";
                }
            }

            private function tree_labelFunc(item:Object):String {
                var suffix:String = "";
                if (tree.dataDescriptor.isBranch(item)) {
                    suffix = " (" + item.children().length() + ")";
                }
                return item.@label + suffix;
            }

        ]]>
    </mx:Script>

   <mx:XML id="dp" source="dp2.xml" />
            <mx:Tree id="tree"
                    dataProvider="{dp}"
                    labelFunction="tree_labelFunc"
                    showRoot="false"
                    width="100%"
                    height="100%"
                    itemClick="tree_itemClick(event);" />
</mx:Application>