好吧,我的想法是使用 ItemRenderer 子类来处理翻转事件并获取项目索引。默认情况下,TabBar 项渲染器是带有 TabBarButtonSkin 皮肤的 ButtonBarButton 类。并且 ButtonBarButton 类具有 itemIndex 属性。我们开始做吧:
---> MyButtonBarItemRenderer.mxml 的代码
<?xml version="1.0" encoding="utf-8"?>
<s:ButtonBarButton xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
creationComplete="creationCompleteHandler(event)"
skinClass="spark.skins.spark.TabBarButtonSkin"
>
<fx:Script>
<![CDATA[
import events.MyTabBarEvent;
import mx.events.FlexEvent;
protected function creationCompleteHandler(event:FlexEvent):void
{
this.addEventListener(MouseEvent.ROLL_OVER, rollOverHandler);
}
private function rollOverHandler(e:MouseEvent) : void
{
var tbe:MyTabBarEvent = new MyTabBarEvent(MyTabBarEvent.ITEM_ROLL_OVER, true);
tbe.itemIndex = this.itemIndex;
dispatchEvent(tbe);
}
]]>
</fx:Script>
</s:ButtonBarButton>
这里我们使用带有 itemIndex 属性的自定义事件:
---> MyTabBarEvent.as 的代码放置在“事件”包中
package events
{
import flash.events.Event;
public class MyTabBarEvent extends Event
{
public static const ITEM_ROLL_OVER:String = "MyTabBarEvent.ItemRollOver";
public var itemIndex:int;
public function MyTabBarEvent(type:String, bubbles:Boolean=false, cancelable:Boolean=false)
{
super(type, bubbles, cancelable);
}
}
}
我们现在要做的就是在我们的应用程序中处理我们的自定义事件:
---> 应用代码
<?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"
creationComplete="creationCompleteHandler(event)"
>
<fx:Declarations>
<!-- Place non-visual elements (e.g., services, value objects) here -->
</fx:Declarations>
<fx:Script>
<![CDATA[
import events.MyTabBarEvent;
import mx.events.FlexEvent;
protected function creationCompleteHandler(event:FlexEvent):void
{
tabBar.addEventListener(MyTabBarEvent.ITEM_ROLL_OVER, itemRollOverHandler);
}
protected function itemRollOverHandler(e:MyTabBarEvent) : void
{
trace ("Item " + e.itemIndex + " roll over event handled");
tabBar.selectedIndex = e.itemIndex;
}
]]>
</fx:Script>
<s:VGroup>
<s:TabBar id="tabBar" dataProvider="{viewstckId}" width="100%" itemRenderer="MyButtonBarItemRenderer"/>
<mx:ViewStack id="viewstckId">
<s:NavigatorContent label="Title 1">
<s:Panel title="title - 1"/>
</s:NavigatorContent >
<s:NavigatorContent label="Title 2">
<s:Panel title="title - 2"/>
</s:NavigatorContent>
<s:NavigatorContent label="Title 3">
<s:Panel title="title - 3"/>
</s:NavigatorContent>
</mx:ViewStack>
</s:VGroup>
</s:Application>