flex list组件增加删除
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<s:layout>
<s:VerticalLayout verticalAlign="middle" horizontalAlign="center" />
</s:layout>

<fx:Script>
<![CDATA[
import mx.collections.ArrayCollection;
import mx.controls.Alert;
import mx.events.FlexEvent;

[Bindable]
private var m:ContextMenu;

[Bindable]
private var d:ArrayCollection = new ArrayCollection([
{id:1,city:"湖南"},
{id:1,city:"湖北"},
{id:3,city:"上海"}]);

private function addData():void
{
var obj:Object=new Object();
obj.id=d.length;
obj.city=t.text;
d.addItem(obj);

t.text='';
}

private function deleteData():void{
d.removeItemAt(lists.selectedIndex);
}
]]>
</fx:Script>

<fx:Declarations>
<!-- 将非可视元素（例如服务、值对象）放在此处 -->
</fx:Declarations>

<s:List id="lists" dataProvider="{d}" labelField="city" width="200" height="200"></s:List>

<s:TextInput id="t" width="200"/>

<s:HGroup width="200" height="30" verticalAlign="middle" horizontalAlign="center">
<s:Button label="添加" enabled="{t.text==''?false:true}" click="addData()" />
<s:Button label="删除" enabled="{lists.selectedIndex==-1?false:true}" click="deleteData()" />
</s:HGroup>
</s:Application>