Flex中自定义事件

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<?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:Metadata>
  [Event("showYaner")]
</fx:Metadata>
<fx:Script>
  <![CDATA[
   import mx.controls.Alert;
   import mx.events.FlexEvent;

   //应用程序启动时注册监听
   protected function creationCompleteHandler(event:FlexEvent):void
   {
    this.addEventListener("showYaner", showHandler);
   }

   //监听响应函数
   private function showHandler(e:Event):void
   {
    Alert.show("我的老婆，想你");
   }

]]>
</fx:Script>

<s:Button id="eventTest" label="wife" width="20" height="20" click="{dispatchEvent(new Event('showYaner'))}"/>
</s:Application>

另一种事件响应方式（即从一个组件中监听另一个组件的方法）

<?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" xmlns:local="*">
<s:layout>
  <s:BasicLayout/>
</s:layout>
<fx:Declarations>
  
</fx:Declarations>
<fx:Script>
  <![CDATA[
   import mx.controls.Alert;
   private function mytestHander():void
   {
    Alert.show("===我的小艳儿===");
   }
  ]]>
</fx:Script>
<local:Mycanvas myyaner="mytestHander()"/>
</s:Application>

---Mycanvas 组件

<?xml version="1.0" encoding="utf-8"?>
<mx:Canvas 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">
<fx:Declarations>
  
</fx:Declarations>
<fx:Metadata>
  [Event(name='myyaner', type='flash.events.Event')]
</fx:Metadata>
<s:Button id="yanerbtn" label="事件测试" click="{dispatchEvent(new Event('myyaner'))}"/>
</mx:Canvas>

还有一点需要注意，也是自己在平时中总结出来的，就是，事件只能在父类中添加监听，在当前类或是子类中触发。不能与不相关（平级的组件）之间调用：如：

<?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"

xmlns:local="*" creationComplete="application1_creationCompleteHandler(event)">

<fx:Metadata>

[Event(name="bookSelected", type="events.Event")]

</fx:Metadata>

<fx:Script>

<![CDATA[

import events.BookEntryEvent;

import mx.controls.Alert;

import mx.events.FlexEvent;

protected function button1_clickHandler(event:MouseEvent):void

{

this.dispatchEvent(new Event("bookSelected"));

}

protected function application1_creationCompleteHandler(event:FlexEvent):void

{

this.addEventListener("bookSelected", onBookSelectEventHandler);

}

private function onBookSelectEventHandler(e:Event):void

{

Alert.show("自定义监听的事件");

}

]]>

</fx:Script>

<s:Button x="127" y="134" label="触发事件" width="202" height="38" click="button1_clickHandler(event)"/>

<local:listenerTest/>

</s:Application>

<?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="group1_creationCompleteHandler(event)">

<s:layout>

<s:BasicLayout/>

</s:layout>

<fx:Script>

<![CDATA[

import events.BookEntryEvent;

import mx.controls.Alert;

import mx.events.FlexEvent;

protected function group1_creationCompleteHandler(event:FlexEvent):void

{

mybtn.addEventListener("bookSelected", onBookSelectEventHandler);

}

private function onBookSelectEventHandler():void

{

Alert.show("自定义监听的事件");

}

]]>

</fx:Script>

<fx:Declarations>

</fx:Declarations>

<s:Button label="45234drfsdfsdf" x="100" id="mybtn"/>

</s:Group>

上面举得这个示例，就不能派发Group中的事件。如果是使用父类与子类关系的事件监听的话，一定要把new Event()中的bubbles属性设置为true，表示该事件为冒泡事件。否则，事件不会派发。