ComboBox控件

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" creationComplete="initUI()">
    <mx:ComboBox x="10" y="10" id="bookList"></mx:ComboBox>
    <mx:TextArea x="10" y="51" height="92" id="tip_txt"/>
    <mx:Script>
        <![CDATA[
            import mx.events.DropdownEvent;
            internal function initUI():void{
                var info:Array=new Array();
                info.push({label:"Book 1",data:"1"});
                info.push({label:"Book 2",data:"2"});
                info.push({label:"Book 3",data:"3"});
                info.push({label:"Book 4",data:"4"});
                bookList.dataProvider=info;
                bookList.addEventListener(DropdownEvent.CLOSE,choose);
                // DropdownEvent事件，在列表被弹出或收回时，分别触发DropdownEvent对像的open事件和close事件  
            }
            internal function choose(evt:DropdownEvent):void{
                var item:Object=bookList.selectedItem;
                tip_txt.text="Select:Label:"+item.label+";data:"+item.data;
            }
        ]]>
    </mx:Script>
</mx:Application>