MusicControlNotification.java

package com.tanguyantoine.react;

import android.app.PendingIntent;
import android.app.Service;
import android.content.Intent;
import android.content.res.Resources;
import android.os.IBinder;
import android.support.v4.app.NotificationManagerCompat;
import android.support.v4.media.session.PlaybackStateCompat;
import android.support.v7.app.NotificationCompat;
import android.view.KeyEvent;
import com.facebook.react.bridge.ReactApplicationContext;

public class MusicControlNotification {

    protected static final String REMOVE_NOTIFICATION = "music_control_remove_notification";
    protected static final String MEDIA_BUTTON = "music_control_media_button";
    protected static final String PACKAGE_NAME = "music_control_package_name";

    private final ReactApplicationContext context;

    private int smallIcon;
    private NotificationCompat.Action play, pause, stop, next, previous;

    public MusicControlNotification(ReactApplicationContext context) {
        this.context = context;

        Resources r = context.getResources();
        String packageName = context.getPackageName();

        // Optional custom icon with fallback to the play icon
        smallIcon = r.getIdentifier("music-control-icon", "drawable", packageName);
        if(smallIcon == 0) smallIcon = r.getIdentifier("play", "drawable", packageName);
    }

    public void updateActions(long mask) {
        play = createAction("play", "Play", mask, PlaybackStateCompat.ACTION_PLAY, play);
        pause = createAction("pause", "Pause", mask, PlaybackStateCompat.ACTION_PAUSE, pause);
        stop = createAction("stop", "Stop", mask, PlaybackStateCompat.ACTION_STOP, stop);
        next = createAction("next", "Next", mask, PlaybackStateCompat.ACTION_SKIP_TO_NEXT, next);
        previous = createAction("previous", "Previous", mask, PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS, previous);
    }

    public void show(NotificationCompat.Builder builder, boolean isPlaying) {
        // Add the buttons
        builder.mActions.clear();
        if(previous != null) builder.addAction(previous);
        if(play != null && !isPlaying) builder.addAction(play);
        if(pause != null && isPlaying) builder.addAction(pause);
        if(stop != null) builder.addAction(stop);
        if(next != null) builder.addAction(next);

        // Notifications of playing music can't be removed
        builder.setOngoing(isPlaying);
        builder.setSmallIcon(smallIcon);

        // Open the app when the notification is clicked
        String packageName = context.getPackageName();
        Intent openApp = context.getPackageManager().getLaunchIntentForPackage(packageName);
        builder.setContentIntent(PendingIntent.getActivity(context, 0, openApp, 0));

        if(!isPlaying) {
            // Remove notification
            Intent remove = new Intent(REMOVE_NOTIFICATION);
            remove.putExtra(PACKAGE_NAME, context.getApplicationInfo().packageName);
            builder.setDeleteIntent(PendingIntent.getBroadcast(context, 0, remove, PendingIntent.FLAG_UPDATE_CURRENT));
        }

        // Finally show/update the notification
        NotificationManagerCompat.from(context).notify("MusicControl", 0, builder.build());
    }

    public void hide() {
        NotificationManagerCompat.from(context).cancel("MusicControl", 0);
    }

    /**
     * Code taken from newer version of the support library located in PlaybackStateCompat.toKeyCode
     * Replace this to PlaybackStateCompat.toKeyCode when React Native updates the support library
     */
    private int toKeyCode(long action) {
        if(action == PlaybackStateCompat.ACTION_PLAY) {
            return KeyEvent.KEYCODE_MEDIA_PLAY;
        } else if(action == PlaybackStateCompat.ACTION_PAUSE) {
            return KeyEvent.KEYCODE_MEDIA_PAUSE;
        } else if(action == PlaybackStateCompat.ACTION_SKIP_TO_NEXT) {
            return KeyEvent.KEYCODE_MEDIA_NEXT;
        } else if(action == PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS) {
            return KeyEvent.KEYCODE_MEDIA_PREVIOUS;
        } else if(action == PlaybackStateCompat.ACTION_STOP) {
            return KeyEvent.KEYCODE_MEDIA_STOP;
        } else if(action == PlaybackStateCompat.ACTION_FAST_FORWARD) {
            return KeyEvent.KEYCODE_MEDIA_FAST_FORWARD;
        } else if(action == PlaybackStateCompat.ACTION_REWIND) {
            return KeyEvent.KEYCODE_MEDIA_REWIND;
        } else if(action == PlaybackStateCompat.ACTION_PLAY_PAUSE) {
            return KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE;
        }
        return KeyEvent.KEYCODE_UNKNOWN;
    }

    private NotificationCompat.Action createAction(String iconName, String title, long mask, long action, NotificationCompat.Action oldAction) {
        if((mask & action) == 0) return null; // When this action is not enabled, return null
        if(oldAction != null) return oldAction; // If this action was already created, we won't create another instance

        // Finds the icon with the given name
        Resources r = context.getResources();
        String packageName = context.getPackageName();
        int icon = r.getIdentifier(iconName, "drawable", packageName);

        // Creates the intent based on the action
        int keyCode = toKeyCode(action);
        Intent intent = new Intent(MEDIA_BUTTON);
        intent.putExtra(Intent.EXTRA_KEY_EVENT, new KeyEvent(KeyEvent.ACTION_DOWN, keyCode));
        intent.putExtra(PACKAGE_NAME, packageName);
        PendingIntent i = PendingIntent.getBroadcast(context, keyCode, intent, PendingIntent.FLAG_UPDATE_CURRENT);

        return new NotificationCompat.Action(icon, title, i);
    }

    public static class NotificationService extends Service {
        @Override
        public IBinder onBind(Intent intent) {
            return null;
        }

        @Override
        public int onStartCommand(Intent intent, int flags, int startId) {
            return START_NOT_STICKY;
        }

        @Override
        public void onTaskRemoved(Intent rootIntent) {
            // Destroy the notification and sessions when the task is removed (closed, killed, etc)
            if(MusicControlModule.INSTANCE != null) {
                MusicControlModule.INSTANCE.destroy();
            }
            stopSelf(); // Stop the service as we won't need it anymore
        }

    }

}