arjunv

{
    "key_events": {
        "key_unknown": "adb shell input keyevent 0",
        "key_soft_left": "adb shell input keyevent 1",
        "key_soft_right": "adb shell input keyevent 2",
        "key_home": "adb shell input keyevent 3",
        "key_back": "adb shell input keyevent 4",
        "key_call": "adb shell input keyevent 5",
        "key_endcall": "adb shell input keyevent 6",
        "key_0": "adb shell input keyevent 7",

kwong93

// Took forever because of crappy tutorials, for example https://developer.android.com/guide/topics/media-apps/audio-app/building-a-mediabrowserservice.html
// Key information was in COMMENTS in MediaButtonReceiver.java
// The key is to have a receiver with filter android.intent.action.MEDIA_BUTTON AND in the service

// register pending intent to the button in notification
builder.addAction(new NotificationCompat.Action(
        R.drawable.ic_skip_next_black_24dp, getString(R.string.skip_next),
        MediaButtonReceiver.buildMediaButtonPendingIntent(this, PlaybackStateCompat.ACTION_SKIP_TO_NEXT)));

// manifest changes