Handler

1.Handler-----更新UI+消息处理机制

  handler.  sendMessage()    

                 sendMessageDealyed()  

                 post(Runnable runnable)

                 postDealyed(Runnable runnable,long time)

2.Message message=new Message() ;            /          Message message=Message.obtainMessage();

   message.arg1  =  (int型）;

   message.arg2 =  (int型）;

   message.obj    =（一个类的对象）;

   handler.sendMessage(message);                /           message.sendToTarget();

3.主线程中：Handler handler=new  Handler(){

                            public void handleMessage(Message msg){

                                  msg.obj;

                }

};