flex 学习笔记 标签与as里面的类（一）

Flex最强大的特性之一就是它在标签和ActionScript类之间创建了一个简单的映射。

就像下面的样子：
?1 —— 每个标签相当于一个以标签名为类名的类的一个实例。
?2—— 标签的每个属性（attribute）转变为对象中的一个property。
?3—— 每个标签中的id属性转变为相应实例中的一个变量。

例如? 类：

 
 

public?class?Contact ?
  
  
{ ?
  
  
????public?var?home?:?Location; ?
  
  
????public?var?work?:?Location; ?
  
  
????public?var?firstname?:?String; ?
  
  
????public?var?lastname?:?String; ?
  
  

????public?var?isFriend?:?Boolean?=?false; ?

  
  
} ?
 
 

标签：<Contact id="myContact" firstname="Susan" lastname="Smith" isfriend="true" />

相当于：

 
 

var?myContact?:?Contact?=?new?Contact(); ?
  
  

myContact.firstname?=?"Susan"; ?

  
  

myContact.lastname="Smith"; ?

  
  

myContact.isFriend=true; ?

 
 

所以就可以这样:

代码：

 
 

<?xml?version="1.0"?encoding="utf-8"?>?
  
  

<contr:Test05?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:contr="contr.*"?width="400"?height="300">?

  
  

????<fx:Declarations>?

  
  

????????<!--?将非可视元素（例如服务、值对象）放在此处?-->?

  
  

????</fx:Declarations>?

  
  

????<mx:VBox?width="100"?height="100">?

  
  

????????<s:Label?width="30"?height="30"?text="12312"?fontSize="40"/>?

  
  

????</mx:VBox>?

  
  

</contr:Test05>?

 
 

?

 
 

package?contr ?
  
  
{ ?
  
  
????import?flash.events.MouseEvent; ?
  
  
????import?mx.containers.TitleWindow; ?
  
  
????import?mx.controls.Button; ?
  
  
????import?mx.controls.LinkButton; ?
  
  
????import?mx.managers.PopUpManager; ?
  
  
????public?class?Test05?extends?TitleWindow ?
  
  
????{ ?
  
  
????????private?var?helpButton?:?LinkButton; ?
  
  
????????private?var?_closeButton?:?Button; ?
  
  
????????public?function?Test05?() ?
  
  
????????{ ?
  
  

????????????title?=?"Custom?TitleWindow"; ?

  
  

????????????showCloseButton?=?true; ?

  
  
????????} ?
  
  
????????private?function?get?closeButton?()?:?Button ?
  
  
????????{ ?
  
  
????????????if?(!?_closeButton) ?
  
  
????????????{ ?
  
  

????????????????for?(var?i?:?int?=?0;?i?<?titleBar.numChildren;?++?i) ?

  
  
????????????????{ ?
  
  
????????????????????if?(titleBar.getChildAt?(i)?is?Button?&& ?
  
  
????????????????????????titleBar.getChildAt?(i)?!=?helpButton) ?
  
  
????????????????????{ ?
  
  

????????????????????????_closeButton?=?titleBar.getChildAt?(i)?as ?

  
  
????????????????????????????Button; ?
  
  
????????????????????} ?
  
  
????????????????} ?
  
  
????????????} ?
  
  
????????????return?_closeButton; ?
  
  
????????} ?
  
  
????????override?protected?function?createChildren?()?:?void ?
  
  
????????{ ?
  
  
????????????super.createChildren?();???????????????? ?
  
  
????????????if?(!?helpButton) ?
  
  
????????????{ ?
  
  

????????????????helpButton?=?new?LinkButton?(); ?

  
  

????????????????helpButton.label?=?"Help";?????????? ?

  
  

????????????????helpButton.focusEnabled?=?false; ?

  
  
????????????????helpButton.setStyle?("paddingTop",?4); ?
  
  
????????????????titleBar.addChild?(helpButton); ?
  
  
????????????????helpButton.addEventListener(MouseEvent.CLICK,helpClick) ?
  
  

????????????????helpButton.owner?=?this; ?

  
  
????????????} ?
  
  
????????} ?
  
  
????????protected?function?helpClick(event:MouseEvent):void ?
  
  
????????{ ?
  
  
????????????PopUpManager.addPopUp(this,this,true); ?
  
  
????????} ?
  
  
????????override?protected?function?layoutChrome?(w?:?Number,?
  
  
??????????????????????????????????????????????????h?:?Number)?:?void ?
  
  
????????{ ?
  
  
????????????super.layoutChrome?(w,?h); ?
  
  

????????????var?width?:?Number?= ?

  
  

????????????????helpButton.getExplicitOrMeasuredWidth?(); ?

  
  

????????????var?height?:?Number?= ?

  
  

????????????????helpButton.getExplicitOrMeasuredHeight?(); ?

  
  

????????????var?x?:?Number?=?5; ?

  
  

????????????var?y?:?Number?=?5; ?

  
  
????????????helpButton.setActualSize?(width,?height); ?
  
  
????????????helpButton.move?(x,?y); ?
  
  
????????} ?
  
  
????} ?
  
  
}??
 
 

在类里面可以使用任何这个类的属性和方法来定义要使用的组件的样式和事件逻辑。

学习ING。。。。