Android comprehensive failproof music service across multiple activities

Question

I know this question has been asked many times before and might seem to be a conglomeration of several questions, but I feel that it is relevant and important to many develo

Answer 1

First here is some code. Below I'll give you an explanation.

public class MusicService extends Service {

    // service binder
    private final IBinder mBinder = new LocalBinder();

    // music player controling game music
    private static CarefulMediaPlayer mPlayer = null;

    @Override
    public void onCreate() {
        // load music file and create player
        MediaPlayer mediaPlayer = MediaPlayer.create(this, R.raw.title_music);
        mediaPlayer.setLooping(true);
        mPlayer = new CarefulMediaPlayer(mediaPlayer, this);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
    }

    // =========================
    // Player methods
    // =========================
    public void musicStart() {
        mPlayer.start();
    }

    public void musicStop() {
        mPlayer.stop();
    }

    public void musicPause() {
        mPlayer.pause();
    }

    /**
     * Class for clients to access. Because we know this service always runs in
     * the same process as its clients, we don't need to deal with IPC.
     */
    public class LocalBinder extends Binder {
        MusicService getService() {
            return MusicService.this;
        }
    }

    @Override
    public IBinder onBind(Intent arg0) {
        return mBinder;
    }

}

Activity:

public class StartupActivity extends Activity {

// bounded service
private static MusicService mBoundService;

// whetere service is bounded or not
private boolean mIsBound;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_startup);
    doBindService();

    // HOW TO WORK WITH THE SERVICE:
    // call the following methods whenever
    // you want to interact with you 
    // music player
    // ===================================

    // call this e.g. in onPause() of your Activities
    StartupActivity.getService().musicPause();

    // call this e.g. in onStop() of your Activities
    StartupActivity.getService().musicStop();

    // call this e.g. in onResume() of your Activities
    StartupActivity.getService().musicStart();
}

@Override
public void onDestroy() {
    super.onDestroy();
    doUnbindService();
}

private final ServiceConnection mServiceConnection = new ServiceConnection() {

    @Override
    public void onServiceConnected(ComponentName className, IBinder service) {
        setService(((MusicService.LocalBinder) service).getService());
    }

    @Override
    public void onServiceDisconnected(ComponentName className) {
        setService(null);
    }
};

private void doBindService() {
    Intent service = new Intent(getBaseContext(), MusicService.class);
    // start service and bound it
    startService(service);
    bindService(new Intent(this, MusicService.class), mServiceConnection, Context.BIND_AUTO_CREATE);
    mIsBound = true;
}

private void doUnbindService() {
    if (mIsBound) {
        // Detach existing connection.
        unbindService(mServiceConnection);
        mIsBound = false;
    }
}

public static MusicService getService() {
    return mBoundService;
}

private static void setService(MusicService mBoundService) {
    StartupActivity.mBoundService = mBoundService;
}
}

First of all you got a Service which runs in background. This service creates the mediaPlayer object as you did. With the localBinder you can bind the Service in your Activity(ies) and access it like a normal Java-Object. The Activity I've posted bindes the Service. In it's onCreate() method you can find a way how to interact with your mediaPlayer. You can bind any Activity to your Service.

Another Solution:

public class CarefulMediaPlayer {
final SharedPreferences sp;
final MediaPlayer mp;
private boolean isPlaying = false;
private static CarefulMediaPlayer instance;

public CarefulMediaPlayer(final MediaPlayer mp, final MusicService ms) {
    sp = PreferenceManager.getDefaultSharedPreferences(ms.getApplicationContext());
    this.mp = mp;
    instance = this;
}

public static CarefulMediaPlayer getInstance() {
    return instance;
}

public void start() {
    if (sp.getBoolean("com.embed.candy.music", true) && !isPlaying) {
        mp.start();
        isPlaying = true;
    }
}

public void pause() {
    if (isPlaying) {
        mp.pause();
        isPlaying = false;
    }
}

public void stop() {
    isPlaying = false;
    try {
        mp.stop();
        mp.release();
    } catch (final Exception e) {}
}
}

Then you can pause, play and stop the music by calling CarefulMediaPlayer.getInstance().play();