Flex Timer 定時器

flash.util.Timer類

    flash.util.Timer類允許通過添加時間事件或延時來調用方法。通過Timer構造器創建實例對象，傳遞一個毫秒數字作爲構造參數作爲間隔時間，下面的例子實例化一個Timer對象每個1秒鐘發出事件信號： 

   

var  timer.Timer  =   new  Timer( 1000 ); 

 

    一旦創建了Timer實例，下一步必須添加一個事件監聽器來處理髮出的事件，Timer對象發出一個falsh.event.TimerEvent事件，它是根據設置的間隔時間或延時時間定時發出。下面的代碼定義了一個事件監聽，調用onTimer()方法作爲處理函數： 
    

timer.addEventListener(TimerEvent.TIMER, onTimer); 

     function  onTimer(event:TimerEvent): void { 

         trace( " on timer " ); 

    } 

 

    Timer對象不會自動開始，必須調用start()方法啓動： 

 timer.start(); 

 

    默認情況下只有調用stop()方法纔會停下來，不過另一種方法是傳遞給構造器第二個參數作爲運行次數，默認值爲0即無限次，下面的例子設定定時器運行5次： 

  var  timer:Timer  =   new  Timer( 1000 ,  5 ); 

 

    下面的代碼設定定時器延時5秒執行deferredMethod()方法： 

   

var  timer:Timer  =   new  Timer( 5000 ,  1 ); 

timer.addEventListener(TimerEvent.TIMER, deferredMethod); 

timer.start(); 

 

Flex中Timer用法一例：計時器

 

代碼

<? xml version = " 1.0 "  encoding = " utf-8 " ?>     
< mx:Application xmlns:mx = " http://www.adobe.com/2006/mxml "     
        layout = " vertical "     
        verticalAlign = " middle "     
        backgroundColor = " white "     
        creationComplete = " init() "  viewSourceURL = " srcview/index.html " >     
  
     < mx:Script >     
         <! [CDATA[    
            import flash.utils.Timer;    
            import flash.events.TimerEvent;    
  
            private const MIN_MASK:String  =   " 00 " ;    
            private const SEC_MASK:String  =   " 00 " ;    
            private const MS_MASK:String  =   " 000 " ;    
            private const TIMER_INTERVAL: int   =   10 ;    
  
            private  var  baseTimer: int ;    
  
            private  var  t:Timer;    
  
            private  function  init(): void  {    
                t  =   new  Timer(TIMER_INTERVAL);    
                t.addEventListener(TimerEvent.TIMER, updateTimer);    
            }    
  
            private  function  updateTimer(evt:TimerEvent): void  {    
                 var  d:Date  =   new  Date(getTimer()  -  baseTimer);    
                 var  min:String  =  (MIN_MASK  +  d.minutes).substr( - MIN_MASK.length);    
                 var  sec:String  =  (SEC_MASK  +  d.seconds).substr( - SEC_MASK.length);    
                 var  ms:String  =  (MS_MASK  +  d.milliseconds).substr( - MS_MASK.length);    
                counter.text  =  String(min  +   " : "   +  sec  +   " . "   +  ms);    
            }    
  
            private  function  startTimer(): void  {    
                baseTimer  =  getTimer();    
                t.start();    
            }    
  
            private  function  stopTimer(): void  {    
                t.stop();    
            }    
        ]] >     
     < / mx:Script>    
  
     < mx:ApplicationControlBar dock = " true " >     
         < mx:Button label = " Start timer "  click = " startTimer() "   / >    
         < mx:Button label = " Stop timer "  click = " stopTimer() "   / >    
     < / mx:ApplicationControlBar>       
  
     < mx:Label id = " counter "  fontSize = " 96 "   / >    
  
< / mx:Application>   

 

 

效果圖：

Flex中Timer用法一例：上傳文件（用時）計時器

 

代碼

<? xml version = " 1.0 "  encoding = " utf-8 " ?>  
< mx:Application xmlns:mx = " http://www.adobe.com/2006/mxml "  
        layout = " vertical "  
        verticalAlign = " middle "  
        backgroundColor = " white "  
        creationComplete = " init(); " >  
  
     < mx:Script >  
         <! [CDATA[ 
            import flash.net.FileReference; 
            import flash.net.URLRequestMethod; 
            import mx.controls.Alert; 
            import mx.utils.StringUtil; 
  
            private  var  fileRef:FileReference; 
            private  var  urlVars:URLVariables; 
            private  var  urlReq:URLRequest; 
            private  var  startTimer:Number; 
            private  var  timer:Timer; 
  
            private  function  init(): void  { 
                fileRef  =   new  FileReference(); 
                fileRef.addEventListener(Event.SELECT, fileRef_select); 
                fileRef.addEventListener(Event.COMPLETE, fileRef_complete); 
                fileRef.addEventListener(IOErrorEvent.IO_ERROR, fileRef_ioError); 
  
                urlVars  =   new  URLVariables(); 
                urlVars.userID  =   94103 ; 
                urlVars.fpVersion  =  flash.system.Capabilities.version; 
  
                urlReq  =   new  URLRequest(); 
                urlReq.method  =  URLRequestMethod.POST; 
                urlReq.data  =  urlVars; 
                urlReq.url  =   " http://localhost:8300/fileref/uploader.aspx " ; 
  
                timer  =   new  Timer( 100 ); 
                timer.addEventListener(TimerEvent.TIMER, onTimer); 
            } 
  
            private  function  onTimer(evt:TimerEvent): void  { 
                lbl.text  =  String(getTimer()  -  startTimer)  +   "  ms " ; 
            } 
  
            private  function  start(): void  { 
                fileRef.browse(); 
            } 
  
            private  function  fileRef_select(evt:Event): void  { 
                fileRef.upload(urlReq); 
                startTimer  =  getTimer(); 
                timer.start(); 
            } 
  
            private  function  fileRef_complete(evt:Event): void  { 
                Alert.show(evt.toString(), evt.type); 
                timer.stop(); 
            } 
  
            private  function  fileRef_ioError(evt:IOErrorEvent): void  { 
                Alert.show(evt.text, evt.type); 
                timer.stop(); 
            } 
        ]] >  
     < / mx:Script> 
  
     < mx:Button label = " upload "  click = " start(); "   / > 
     < mx:Label id = " lbl "   / > 
  
< / mx:Application>

 

 

效果圖：
 

轉載於:https://www.cnblogs.com/qiantuwuliang/archive/2010/04/09/1708026.html