How to fix 'media button receiver could not be found' exception

Question

I'm building media player, and want to handle action from notification like "play", "pause". In my activity I registerd MediaButtonReceiver

registerReceiver(MediaButtonReceiver(), IntentFilter(Intent.ACTION_MEDIA_BUTTON))

and created media notification with

val builder: NotificationCompat.Builder = MediaStyleHelper.from(this, mediaSession!!)
builder.addAction(
                NotificationCompat.Action(
                        android.R.drawable.ic_media_previous,
                        "Previous",
                        MediaButtonReceiver.buildMediaButtonPendingIntent(this, PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS)
                )
        )

but when I press action buttons on my media notification, nothing happens. And when I add these actions, executing

MediaButtonReceiver.buildMediaButtonPendingIntent(this, PlaybackStateCompat.ACTION_SKIP_TO_PREVIOUS)

prints to console a warning

"W/MediaButtonReceiver: A unique media button receiver could not be found in the given context, so couldn't build a pending intent."

But why is it not registered if I have registered it programmatically?

Answer 1

Before you can use MediaButtonReceiver functions, you need to add it to the manifest as described in the docs:

<receiver android:name="androidx.media.session.MediaButtonReceiver" >
  <intent-filter>
    <action android:name="android.intent.action.MEDIA_BUTTON" />
  </intent-filter>
</receiver>

If you aren't using the AndroidX libraries yet, you need to use the old class name: android.support.v4.media.session.MediaButtonReceiver