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FLEX 事件机制-自定义事件

最近在做地图JS和FLEX的封装工作,flex封装需要用到自定义事件这方面知识,在这里就简单介绍一下FLEX自定义事件。
自定义事件必须注意几点:
        (1)自定义事件通过继承Event类来实现。
        (2)自定义事件不可以自己触发,只能有系统事件派发。 package { import flash.events.Event; public class MyEvent extends Event { public static const myEvent:String="myEvent"; public var data:*; public function MyEvent(type:String,bubbles:Boolean=false,cancellabel:Boolean=false,data:* = null) { super(type,false,false); this.data = data; } override public function clone():Event{ return new MyEvent(myEvent,false,false,data); } override public function toString():String{ return formatToString("MyEvent"); } } }

 

首先我们新建一个ActionScript 类,这个类继承flash.events.Event。     
 
 
创建一个组件来监听事件,实现数据的接受。
component.mxml
  <?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="100%" height="100%" initialize="init()"> <s:layout> <s:BasicLayout/> </s:layout> <fx:Script> <![CDATA[ import mx.controls.Alert; import mx.events.FlexEvent; public var ff:FlexMyEvent; public function init():void{ ff = this.parentDocument as FlexMyEvent; ff.addEventListener(MyEvent.myEvent,myEventHandler);//监听事件 } public function myEventHandler(eve:Object):void{ inpu.text = eve.data; Alert.show("事件触发,"+eve.data); } ]]> </fx:Script> <fx:Declarations> <!-- 将非可视元素(例如服务、值对象)放在此处 --> </fx:Declarations> <s:Panel width="100%" height="100%" backgroundColor="#E7D4DD"> <s:TextInput id="inpu"> </s:TextInput> </s:Panel>

 

      
</s:Group>  
主程序
FlexMyEvent.mxml
  <?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" xmlns:comp = "*" width="100%" height="100%"> <fx:Script> <![CDATA[ import flash.external.ExternalInte易做图ce; import flash.system.Security; import mx.controls.Alert; import mx.events.FlexEvent; public var callBackInfo:String = ""; public function doSend():void{ callBackInfo = input.text; var myEve:MyEvent = new MyEvent(MyEvent.myEvent,false,false,callBackInfo);//派发事件 myEve.data is Object; this.dispatchEvent(myEve); } ]]> </fx:Script> <fx:Declarations> <!-- 将非可视元素(例如服务、值对象)放在此处 --> </fx:Declarations> <mx:HBox width="100%" height="100%" horizontalAlign="center" verticalAlign="middle"> <s:Panel width="100%" height="100%"> <mx:HBox paddingLeft="5" width="100%" height="100%"> <s:TextInput id="input" text="Send Hello"> </s:TextInput> <s:Button label="Send" click="doSend()"> </s:Button> </mx:HBox> </s:Panel> <comp:Component> </comp:Component> </mx:HBox> </s:Application>

 

 
补充:web前端 , HTML/CSS  ,
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