Android 三种延迟操作的实现方法

new Thread(new Runnable(){   
   public void run(){   
     Thread.sleep(XXXX);   
     handler.sendMessage();----告诉主线程执行任务   
   }   
}).start   

 TimerTask task = new TimerTask(){   
   public void run(){   
   //execute the task    
   }   
 };   
 Timer timer = new Timer();  

new Handler().postDelayed(new Runnable(){   
  public void run() {   
  //execute the task   
  }   
 }, delay);