Handler应用3 — 与Activity不同一线程

MainActivity：

package com.example.handlerthread;

import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;

@SuppressLint("HandlerLeak")
public class MainActivity extends Activity {

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        //声明一个Handler线程
        HandlerThread hdt = new HandlerThread("myHandlerThread");
        //在getLooper()之前要先start线程！！！
        hdt.start();
        MyHandler myhandler = new MyHandler(hdt.getLooper());
        //得到handler的Message
        Message msg = myhandler.obtainMessage();

        //bundle用于数据打包传送
        Bundle bundle = new Bundle();
        bundle.putInt("age", 20);
        bundle.putString("name", "Human");
        bundle.putFloat("Score", 99.9f);
        //Message的setData
        msg.setData(bundle);
        //把msg送到Target处（生产msg的handler处）
        msg.sendToTarget();

    }

    class MyHandler extends Handler {
        public MyHandler() {
        }
        //构造函数，参数为Looper
        public MyHandler(Looper looper) {
            super(looper);
        }
        
        //重写父类的handleMessage方法
        //当handler得到msg后就执行handleMessage方法
        public void handleMessage(Message msg) {
            Bundle bd = msg.getData();
            int age = bd.getInt("age");
            System.out.println(age);
        }
    }
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
}