任意地方监听同一事件

基本原理：使用同一个事件调度类。调度类可以扩展EventDispatcher，或者直接使用EventDispatcher，或者实现IEventDispatcher。

在flex中中新建一个EventDispatcher对象作为共享对象，用它抛出事件对象，然后在任意需要监听这个事件对象的取得这个共享的EventDispatcher，并添加监听处理函数或方法。

例子1：使用同一父亲的EventDispatcher。EventDispatcher是 DisplayObject 类的基类。

test.mxml

<?xml version="1.0" encoding="utf-8"?> <s:WindowedApplication xmlns:fx="http://ns.adobe.com/mxml/2009"         xmlns:s="library://ns.adobe.com/flex/spark"         xmlns:mx="library://ns.adobe.com/flex/mx"  xmlns:c="customer.*">  <fx:Script>   <![CDATA[    import mx.events.FlexEvent;    import customer.CustomEvent;   ]]>  </fx:Script>  <s:Group>    <s:layout>  <s:HorizontalLayout /> </s:layout>  <c:CustomCanvas2 id="main"  height="108" width="168"/>  <c:CustomCanvas1 id="two"  height="108"/>  </s:Group> </s:WindowedApplication>

CustomCanvas2

<?xml version="1.0" encoding="utf-8"?> <s:Group xmlns:fx="http://ns.adobe.com/mxml/2009"    xmlns:s="library://ns.adobe.com/flex/spark"    xmlns:mx="library://ns.adobe.com/flex/mx" width="400" height="300">  <s:layout>   <s:BasicLayout/>  </s:layout>  <fx:Declarations>   <!-- 将非可视元素（例如服务、值对象）放在此处 -->  </fx:Declarations>  <mx:Canvas width="160" height="100" backgroundColor="#E5E4E4">   <fx:Script>    <![CDATA[    private function clickHandler(event:MouseEvent):void{    var custom:CustomEvent=new CustomEvent(CustomEvent.EVENT_NAME);    //custom.data is Object;//发送事件同时，可以传值(可传可不传)    custom.data=mytxt.text;    this.parent.dispatchEvent(custom);    }    ]]>   </fx:Script>   <mx:TextInput id="mytxt" text="CustomEvent Data" width="140" x="10" y="10"/>   <mx:Button click="clickHandler(event);" label="Send CustomEvent" x="10" y="40"/>  </mx:Canvas> </s:Group>

CustomCanvas1

<?xml version="1.0" encoding="utf-8"?> <s:Group xmlns:fx="http://ns.adobe.com/mxml/2009"    xmlns:s="library://ns.adobe.com/flex/spark"    xmlns:mx="library://ns.adobe.com/flex/mx" width="400" height="300" creationComplete="init();">  <s:layout>   <s:BasicLayout/>  </s:layout>  <fx:Declarations>   <!-- 将非可视元素（例如服务、值对象）放在此处 -->  </fx:Declarations>  <mx:Canvas  width="150" height="100" backgroundColor="#E5E4E4">   <fx:Script>    <![CDATA[    import mx.controls.Alert;    private function init():void{    this.parent.addEventListener(CustomEvent.EVENT_NAME,clickHandler);    }    private function clickHandler(event:CustomEvent):void{    trace("I get it !");    mylb.text=event.data.toString();    Alert.show(event.toString()+"\n"+event.data.toString())    }    ]]>   </fx:Script>   <mx:TextArea id="mylb" x="10" y="10" width="130" height="80"/>  </mx:Canvas> </s:Group>

 

方法2：

test.mxml

同上

CustomCanvas1

<?xml version="1.0" encoding="utf-8"?> <s:Group xmlns:fx="http://ns.adobe.com/mxml/2009"    xmlns:s="library://ns.adobe.com/flex/spark"    xmlns:mx="library://ns.adobe.com/flex/mx" width="400" height="300" creationComplete="init();">  <s:layout>   <s:BasicLayout/>  </s:layout>  <fx:Declarations>   <!-- 将非可视元素（例如服务、值对象）放在此处 -->  </fx:Declarations>  <mx:Canvas  width="150" height="100" backgroundColor="#E5E4E4">   <fx:Script>    <![CDATA[    import mx.controls.Alert;    private function init():void{    CustomEvent.dispatcher.addEventListener(CustomEvent.EVENT_NAME,clickHandler);    }    private function clickHandler(event:CustomEvent):void{    trace("I get it !");    mylb.text=event.data.toString();    Alert.show(event.toString()+"\n"+event.data.toString())    }    ]]>   </fx:Script>   <mx:TextArea id="mylb" x="10" y="10" width="130" height="80"/>  </mx:Canvas> </s:Group>

CustomCanvas2

<?xml version="1.0" encoding="utf-8"?> <s:Group xmlns:fx="http://ns.adobe.com/mxml/2009"    xmlns:s="library://ns.adobe.com/flex/spark"    xmlns:mx="library://ns.adobe.com/flex/mx" width="400" height="300">  <s:layout>   <s:BasicLayout/>  </s:layout>  <fx:Declarations>   <!-- 将非可视元素（例如服务、值对象）放在此处 -->  </fx:Declarations>  <mx:Canvas width="160" height="100" backgroundColor="#E5E4E4">   <fx:Script>    <![CDATA[    private function clickHandler(event:MouseEvent):void{    var custom:CustomEvent=new CustomEvent(CustomEvent.EVENT_NAME);    //custom.data is Object;//发送事件同时，可以传值(可传可不传)    custom.data=mytxt.text;    CustomEvent.dispatcher.dispatchEvent(custom);    }    ]]>   </fx:Script>   <mx:TextInput id="mytxt" text="CustomEvent Data" width="140" x="10" y="10"/>   <mx:Button click="clickHandler(event);" label="Send CustomEvent" x="10" y="40"/>  </mx:Canvas> </s:Group>

CustomEvent.as

package customer {  import flash.events.Event;  import flash.events.EventDispatcher;  public class CustomEvent extends Event  {   public static const EVENT_NAME:String="event_name";      public static const dispatcher:EventDispatcher=new EventDispatcher();   public var data:Object;      public function CustomEvent(type:String, bubbles:Boolean=false, cancelable:Boolean=false, data:Object=null)   {    super(type, bubbles, cancelable);    this.data=data;   }   override public function clone():Event{    return new CustomEvent(type, bubbles, cancelable, data);   }  } }