Android非UI主线程中，若干普通Java线程使用Handler发送接收消息

小鱼儿 2023-10-17 18:14 37阅读 0赞

**Android非UI主线程中，若干普通Java线程使用Handler发送接收消息**

线程1和线程2均为普通Java线程，在Android中创建，然后在这两个普通Java线程中使用Handler发送和接收消息。

import android.os.Handler;
    import android.os.Looper;
    import android.os.Message;
    import android.os.SystemClock;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.util.Log;
    
    public class MainActivity extends AppCompatActivity {
    
        private final String TAG = "输出";
        private final int WHAT = 0xa01;
    
        private Handler handler;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            Log.d(TAG, "Android主线程id:" + Thread.currentThread().getId());
    
            new Thread(new Runnable() {
                @Override
                public void run() {
                    Log.d(TAG, "线程1的id:" + Thread.currentThread().getId());
    
                    Looper.prepare();
                    handler = new Handler() {
                        @Override
                        public void handleMessage(Message msg) {
                            if (msg.what == WHAT) {
                                Log.d(TAG, msg.obj + "@" + System.currentTimeMillis());
                                handler.removeMessages(WHAT);
                            }
                        }
                    };
                    Looper.loop();
                }
            }).start();
    
            new Thread(new Runnable() {
                @Override
                public void run() {
                    Log.d(TAG, "线程2的id:" + Thread.currentThread().getId());
    
                    while (true) {
                        if (handler != null) {
                            Message msg = handler.obtainMessage();
                            msg.what = WHAT;
                            msg.obj = Thread.currentThread().getId() + "";
                            handler.sendMessage(msg);
    
                            SystemClock.sleep(1000);
                        }
                    }
                }
            }).start();
        }
    }

输出：

02-09 09:39:01.029 12544-12544/com.example.fly.myapplication D/输出: Android主线程id:1
    02-09 09:39:01.030 12544-12628/com.example.fly.myapplication D/输出: 线程1的id:12146
    02-09 09:39:01.032 12544-12629/com.example.fly.myapplication D/输出: 线程2的id:12147
    02-09 09:39:01.033 12544-12628/com.example.fly.myapplication D/输出: 12147@1518140341033
    02-09 09:39:02.033 12544-12628/com.example.fly.myapplication D/输出: 12147@1518140342033
    02-09 09:39:03.033 12544-12628/com.example.fly.myapplication D/输出: 12147@1518140343033
    02-09 09:39:04.034 12544-12628/com.example.fly.myapplication D/输出: 12147@1518140344034

......

附：

1，《Android Handler，Looper，Message》链接：http://blog.csdn.net/zhangphil/article/details/43878993