Android中Handler的使用方法——在子线程中更新界面

private void updateUIByRunnable(){
          new Thread() 
         { 
               //Message msg = mHandler.obtainMessage(); 
              public void run() 
             {

                   //mText.setText("This is Update from ohter thread, Mouse DOWN");//这句将抛出异常
                   mHandler.post(mRunnable0); 
             } 
         }.start();

     }

◆ 用Message在子线程中来更新界面

1.     用Message更新界面与Runnable更新界面类似，只是需要修改几个地方。

    ○ 实现自己的Handler，对消息进行处理

private class MyHandler extends Handler
    {

        @Override
        public void handleMessage(Message msg) {
            // TODO Auto-generated method stub
            super.handleMessage(msg);
            switch(msg.what)
            {
            case UPDATE://在收到消息时，对界面进行更新
                mText.setText("This update by message");
                break;
            }
        }
    }

○ 在新的线程中发送消息
private void updateByMessage()
    {
        //匿名对象
         new Thread()
         {
                public void run()
                {
                    //mText.setText("This is Update from ohter thread, Mouse DOWN");

                    //UPDATE是一个自己定义的整数，代表了消息ID
                    Message msg = mHandler.obtainMessage(UPDATE);
                    mHandler.sendMessage(msg);
                }
         }.start();
    }