使用Messenger 从Activity发送数据到service 通过后台计算结果Log输出；

package com.lixu.messenger;

import android.app.Activity;
import android.app.Service;
import android.content.ComponentName;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.os.RemoteException;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity implements OnClickListener {
    private ServiceConnection sc;
    private Messenger sender;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button btn1 = (Button) findViewById(R.id.btn1);
        Button btn2 = (Button) findViewById(R.id.btn2);

        btn1.setOnClickListener(this);
        btn2.setOnClickListener(this);

    }

    public void bindService() {
        sc = new ServiceConnection() {

            @Override
            public void onServiceDisconnected(ComponentName name) {

            }

            @Override
            public void onServiceConnected(ComponentName name, IBinder service) {
                sender = new Messenger(service);
            }

        };
        Intent intent = new Intent(this, MyMessenger.class);
        bindService(intent, sc, Service.BIND_AUTO_CREATE);
        Log.e("开始绑定", "绑定成功");

    }

    public void startService() {
        Intent it = new Intent(this, MyMessenger.class);
        startService(it);
        Message msg = new Message();
        int[] num = { 309, 713 };
        msg.obj = num;
        msg.what = Changliang.WHAT;
        try {
            sender.send(msg);
        } catch (RemoteException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.btn1:
            bindService();
            break;
        case R.id.btn2:
            startService();
            break;

        default:
            break;
        }

    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        unbindService(sc);
        Intent it = new Intent(this, MyMessenger.class);
        stopService(it);

    }
}

package com.lixu.messenger;

import android.app.Service;
import android.content.Intent;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.Messenger;
import android.util.Log;

public class MyMessenger extends Service {
    private int a;
    private int b;
    private Messenger mMessenger;
    
    @Override
    public void onCreate() {
        super.onCreate();
        Handler handler = new Handler() {
            @Override
            public void handleMessage(Message msg) {
                super.handleMessage(msg);
                if (msg.what == Changliang.WHAT) {
                    int[] nums = (int[]) msg.obj;
                    a = nums[0];
                    b = nums[1];
                }    
            }
        };
        mMessenger=new Messenger(handler);
    }


    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        int numshe = a + b;
        Log.e("服务器收到结果：", numshe + "");
        return super.onStartCommand(intent, flags, startId);
    }

    @Override
    public boolean onUnbind(Intent intent) {
        return super.onUnbind(intent);
    }

    @Override
    public IBinder onBind(Intent arg0) {
        return mMessenger.getBinder();
    }

}