TREE定义
<mx:Tree id="deptTree" width="200" height="98%" dataProvider="{Managers.getOrgManager().groupXML}"
labelField="@name" showRoot="false" fontSize="20" change="deptChangeEvent(event)" />
触发选择
private function initUI():void {
deptTree.expandChildrenOf(deptTree.dataProvider[0], true);
deptTree.selectedIndex = 0;
var event:ListEvent = new ListEvent(ListEvent.CHANGE);
deptTree.dispatchEvent(event);
}