FLEX (actionscript3) 设计回调函数范例

 1 package inc
 2 {
 3     public class EventNotifier
 4     {
 5         private var ie:InterestingEvent;
 6                 private var yesNo:Boolean;
 7         public function EventNotifier(event:InterestingEvent)
 8         {
 9             ie = event;
10                         yesNo = false;
11         }
12         public function readyDoWork():void
13         {
14             trace("哈哈，设定条件");
15                         trace("完成一些任务后，把某个条件设为true");
16                         trace("这样，doWork()就可以工作了");
17                         this.yesNo = true;
18         }
19         public function doWork():void
20         {
21             if (yesNo)
22                         {
23                             //通知interestingEvent说，可以做它该做的事情了
24                             ie.interestingEvent();
25                         }
26             }
27     }
28 }

 1 <?xml version="1.0"?>
 2 <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" xmlns:local="*" creationComplete="init();">
 3     <mx:Script>
 4         <![CDATA[
 5             import inc.*;
 6             private function init():void{
 7                 var callme:CallMe=new CallMe();
 8                 callme.en.readyDoWork();
 9                 callme.en.doWork();
                 trace("done~");
             }
         ]]>
     </mx:Script>
 </mx:Application>

 package inc
 {
     public interface InterestingEvent
     {
         function interestingEvent():void;
     }
 }

 1 package inc
 2 {
 3     public class CallMe implements InterestingEvent
 4     {
 5         public var en:EventNotifier;
 6         public function CallMe()
 7         {
 8              //创建事件通知对象
 9                      //因为稍候要回调它的interestingEvent()方法，所以要把自身传递出去
                      en = new EventNotifier (this);
         }
         
         //当某件事发生后，要让这个方法做的事情
         public function interestingEvent():void
         {
             trace("在这里完成一系列需要回调函数完成的任务");
         }    
     }
 }