Android Messenger sample (1. Server app 2. Client app)

Client_AndroidManifest.xml

<!-- This is Client app -->
<uses-permission android:name="com.miiitv.permission.SERVICE" />

ClientActivity.java

private Messenger mService; 
 
final Messenger mMessenger = new Messenger(new Handler() { 
 
    @Override 
    public void dispatchMessage(Message msg) { 
        switch (msg.what) { 
        case SERV_RES_HAHA: 
            String s = msg.getData().getString("msg"); 
            Bundle data = new Bundle(); 
            data.putString("msg", "fuck"); 
            sendMsg(CLNT_REQ_SURPRISE, data); 
            break; 
        } 
    } 
}); 
 
private void sendMsg(int msgCode, Bundle data) { 
    try { 
        Message msg = Message.obtain(null, msgCode); 
        msg.replyTo = mMessenger;
        if (data != null) { 
            msg.setData(data); 
        } 
        mService.send(msg);
    } catch (RemoteException e) { 
        e.printStackTrace(); 
    } 
}
 
private ServiceConnection servConnection = new ServiceConnection() { 
 
    @Override 
    public void onServiceConnected(ComponentName name, IBinder service) { 
        mService = new Messenger(service);
    } 
 
    @Override 
    public void onServiceDisconnected(ComponentName name) { 
        mService = null; 
    } 
}; 
 
protected void doBindService() { 
    bindService(new Intent("com.miiitv.service.MESSENGER"), servConnection, BIND_AUTO_CREATE); 
    isBound = true; 
} 
 
protected void doUnbindService() { 
    if (isBound) { 
        unbindService(servConnection); 
        isBound = false; 
    } 
} 

Server.java

public class Server extends Service { 
 
    private static final String TAG = "Server"; 
    public static final String ACTION = "com.miiitv.service.MESSENGER"; 
 
    final Messenger mMessenger = new Messenger(new Handler() { 
 
        @Override 
        public void dispatchMessage(Message msg) { 
            switch (msg.what) { 
            case CLNT_REQ_HELLO: 
                Bundle data = new Bundle(); 
                data.putString("msg", "Hello world~"); 
                respClnt(msg.replyTo, SERV_RES_HAHA, data); 
                break; 
            case CLNT_REQ_SURPRISE: 
                String s = msg.getData().getString("msg"); 
                break; 
            } 
        } 
 
        private void respClnt(Messenger clnt, int msgCode, Bundle data) { 
            try { 
                Message msg = Message.obtain(null, msgCode); 
                msg.replyTo = mMessenger;
                if (data != null)
                    msg.setData(data); 
                clnt.send(msg);
            } catch (RemoteException e) { 
                e.printStackTrace(); 
            } 
        } 
    }); 
 
    @Override 
    public IBinder onBind(Intent intent) { 
        Log.e(TAG, "onBind"); 
        return mMessenger.getBinder(); 
    } 
 
    // ...... 
}

Server_AndroidManifest.xml

<!-- This is Server app -->
<permission 
    android:name="com.miiitv.permission.SERVICE" 
    android:protectionLevel="normal" > 
</permission> 
 
<uses-permission android:name="com.miiitv.permission.SERVICE" />

<service 
    android:name="com.miiitv.messenger.Server" 
    android:exported="true" 
    android:permission="com.miiitv.permission.SERVICE" 
    android:process=":remote" >
    <intent-filter> 
        <action android:name="com.miiitv.service.MESSENGER" /> 
    </intent-filter> 
</service> 

這是 Android 跨 process 溝通方式使用 Messenger (信使) 代表這是一個非同步的方式，不需要考慮 concurrent 問題，和 AIDL溝通方式一樣屬於誇 process 溝通，但是此方式需要考慮 concurrent 問題。