as3 创建遮罩层和自定义带参数的事件

package 
{
	import flash.events.Event;
	
	/**
	 * ...
	 * @author chb
	 */
	public class MyEvent extends Event 
	{
		public static const CLICK:String = "click";//常量一定要大写
		private var _number:Number;
		public function MyEvent(type:String){
			super(type);
		}
		//参数，可以有很多个我只写了一个
		public function set number(n:Number):void
		{
			_number = n;
		}
		
		public function get number():Number
		{
			return _number;
		}
		//重写toString方法，这个具体还不太明白但是公司的前辈说要这样写，没添加一个参数方法则在"eventPhase"后面加一个，我现在加的是"number"
		override public function toString():String
		{
			return formatToString("ShowDriftMsgEvent", "type", "bubbles", "cancelable",
									"eventPhase", "number");
		}
	}
	
}

package 
{
	import flash.display.Sprite;
	import flash.display.Graphics;
	import flash.events.EventDispatcher;
	import flash.events.Event;
	import flash.events.MouseEvent;
	import flash.ui.Mouse;
	/**
	 * ...
	 * @author chb
	 */
	public class chb extends Sprite 
	{
		//使用 EventDispatcher 对象注册事件侦听器对象，以使侦听器能够接收事件通知
		private var _myED:EventDispatcher;
		public function chb():void
		{
			trace("进入构造方法");
			_myED = new EventDispatcher();
			setMain();
		}
		
		public function setMain():void
		{
			//用程序绘画一个显示元件
			var mc_show:Sprite = new Sprite();
			var g:Graphics = mc_show.graphics;
			g.lineStyle(0, 0, 1);
			g.beginFill(0xffd700, 1);
			g.drawRect(0, 0, 100, 100);
			g.endFill();
			this.addChild(mc_show);
			
			//用程序绘画一个遮罩元件(遮罩层的背景颜色如何没有关系，但是大小和坐标一定要跟被遮罩的元件一样，这样才能完全遮罩住)
			var mc_mask:Sprite = new Sprite();
			var g:Graphics = mc_mask.graphics;
			g.lineStyle(0, 0, 1);
			g.beginFill(0xffffff, 1);
			g.drawRect(0, 0, 100, 100);
			g.endFill();
			this.addChild(mc_mask);
			
			//设置遮罩元件遮罩显示元件
			mc_show.mask = mc_mask;
			
			//添加显示元件点击事件并发送自定义事件
			mc_show.addEventListener(MouseEvent.CLICK, clickHandle);
			
			//监听自定义事件
			this._myED.addEventListener(MyEvent.CLICK,myEventClickHandle);
			
			
		}
		
		private function clickHandle(e:MouseEvent):void
		{
			//创建一个自定义事件对象
			var mye:MyEvent = new MyEvent(MyEvent.CLICK);
			mye.number = 10;
			//发送带参数的自定义事件
			this._myED.dispatchEvent(mye);
		}
		
		private function myEventClickHandle(e:MyEvent):void
		{
			trace("自定义事件发送过来的值为："+e.number);
		}
	
	}
	
}