Hander----使用

public class MainActivity extends Activity {
    private EditText UITxt;
    private Button updateUIBtn;
    private UIHandler uIhandler;  

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        UITxt = (EditText)findViewById(R.id.ui_txt);
        updateUIBtn = (Button)findViewById(R.id.update_ui_btn);
        updateUIBtn.setOnClickListener(new View.OnClickListener() {  

            public void onClick(View v) {  

                uIhandler= new UIHandler();    //  创建Handler 对象
                UIThread thread = new UIThread();
                thread.start();   //
            }
        });
    }  

    private class UIHandler extends Handler{
        @Override
        public void handleMessage(Message msg) {    //  2 .主线程更新界面

            super.handleMessage(msg);  

            Bundle bundle = msg.getData();
            String color = bundle.getString("color");
            UITxt.setText(color);
	//	if(msg.what == SUCCESS) {		// 当前是访问网络, 去显示图片
	//		ivIcon.setImageBitmap((Bitmap) msg.obj);		// 设置imageView显示的图片
	//	} else if(msg.what == ERROR) {
	//		Toast.makeText(MainActivity.this, "抓去失败", 0).show();
	//	}

        }
    }
	//  子线程 中运行
    private class UIThread extends Thread{
        @Override
        public void run() {
            try {
                Thread.sleep(3000);
            } catch (InterruptedException e) {  

                e.printStackTrace();
            }
            Message msg = new Message();
		// msg.what = SUCCESS;
		// msg.obj = bitmap;
            Bundle bundle = new Bundle();
            bundle.putString("color", "黄色");
            msg.setData(bundle);
            MainActivity.this.uIhandler.sendMessage(msg);    //1 . 子线程发消息

        }
    }
}