Pass an arraylist of strings from activity to service in Android

Question

I've made a functional android application that implements MediaPlayer and I know it's late now but better now than never, I want to implement a service to be able to play media while multitasking on other applications.

Is there a way how can I pass for example an ArrayList of String from activity to the service ? What I have found were information about Custom Objects that are passed through parcelable which I think is not needed.

For example, how I've started my transition:

public class PlayerService extends Service implements MediaPlayer.OnPreparedListener{

    private static final String ACTION_PLAY = "action.PLAY";
    private static final String ACTION_PAUSE = "action.PAUSE";
    private MediaPlayer mediaPlayer = null;

    @Override
    public void onCreate() {
        mediaPlayer = new MediaPlayer();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        if (intent.getAction().equals(ACTION_PLAY)) {
            try {
                if(mediaPlayer.isPlaying()) {
                    mediaPlayer.stop();
                }
                mediaPlayer.reset();
                mediaPlayer.setDataSource(musicUrl.get(position));
                mediaPlayer.setOnPreparedListener(this);
                mediaPlayer.prepareAsync();
            } catch (IOException e) {
                e.printStackTrace();
            }

//            setCurrentSong(myDataList.get(position));
//            morphButton.setState(MorphButton.MorphState.START);
//
//            setHighlight(myDataList.get(currentPosition));
        }

        return START_STICKY;
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onPrepared(MediaPlayer mp) {

    }
}

As you can see, I need to get from an ArrayList the music URL to prepare de MediaPlayer

Answer 1

In your activity, where you bind to the service you can add an ArrayList<String> via the intent:

ServiceConnection serviceConnection = new ServiceConnection() {
    @Override
    public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
    }

    @Override
    public void onServiceDisconnected(ComponentName componentName) {
    }
};  

ArrayList<String> stringList = new ArrayList<>();
stringList.add("a");
stringList.add("b");

Intent i = new Intent(this, BLEDiscoveryService.class);
i.putStringArrayListExtra("list", stringList);

bindService(new Intent(this, MyService.class), serviceConnection, BIND_AUTO_CREATE);

And in your service's onBind() you can retrieve it from the passed intent.

public class LocalBinder extends Binder {
    public MyService getService() {
        return MyService.this;
    }
}

@Override
public void onCreate() {
    super.onCreate();
    binder = new LocalBinder();
}

@Override
public IBinder onBind(Intent intent) {
    ArrayList<String> stringList = intent.getStringArrayListExtra("list");
    return binder;
}