How to modify the auto generated media3 notification?

I build a web radio player with Media3 1.0.0-beta03. I use the sample code from Developers page.

It's generated a media notification automatically but I don't know how to add Title and sub title to this.

Here is my media service:

class PlaybackService : MediaSessionService(), MediaSession.Callback {

    private object LC {
        lateinit var exoPlayer: ExoPlayer
        lateinit var mediaSession: MediaSession
    }

    override fun onCreate() {
        super.onCreate()
        log("----------------------------- MediaSessionService, onCreate")

        LC.exoPlayer = ExoPlayer.Builder(this).build()
        LC.exoPlayer.addListener(ExoListener())
        LC.exoPlayer.setAudioAttributes(AudioAttributes.Builder().setContentType(AUDIO_CONTENT_TYPE_MUSIC).setUsage(USAGE_MEDIA).build(),true)

        LC.mediaSession = MediaSession.Builder(this, LC.exoPlayer).setCallback(this).build()
    }

    override fun onGetSession(controllerInfo: MediaSession.ControllerInfo): MediaSession = LC.mediaSession

    override fun onAddMediaItems(mediaSession: MediaSession, controller: MediaSession.ControllerInfo, mediaItems: MutableList<MediaItem>): ListenableFuture<MutableList<MediaItem>> {
        val updatedMediaItems = mediaItems.map { it.buildUpon().setUri(it.mediaId).build() }.toMutableList()
        return Futures.immediateFuture(updatedMediaItems)
    }

    override fun onDestroy() {
        log("----------------------------- MediaSessionService, onDestroy")
        LC.exoPlayer.stop()
        LC.exoPlayer.release()
        LC.mediaSession.release()
        super.onDestroy()
        exitProcess(0)
    }
}

I tryed the onUpdateNotification

Update :

There is also another way, which I found out does the Job better.

In onCreate() function of MediaSessionService, We can set a MediaNotificationProvider like so.

private lateinit var nBuilder: NotificationCompat.Builder
override fun onCreate(){
    super.onCreate()
    // init notificationCompat.Builder before setting the MediaNotificationProvider
    this.setMediaNotificationProvider(object : MediaNotification.Provider{
            override fun createNotification(
                mediaSession: MediaSession,// this is the session we pass to style
                customLayout: ImmutableList<CommandButton>,
                actionFactory: MediaNotification.ActionFactory,
                onNotificationChangedCallback: MediaNotification.Provider.Callback
            ): MediaNotification {
              createNotification(mediaSession)
           // notification should be created before you return here
                return MediaNotification(NOTIFICATION_ID,nBuilder.build())
            }

            override fun handleCustomCommand(
                session: MediaSession,
                action: String,
                extras: Bundle
            ): Boolean { 
                TODO("Not yet implemented")
            }
        })
}

fun  createNotification(session: MediaSession) {
        val notificationManager: NotificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        notificationManager.createNotificationChannel(NotificationChannel(notification_id,"Channel", NotificationManager.IMPORTANCE_LOW))

        // NotificationCompat.Builder here.
        nBuilder = NotificationCompat.Builder(this,notification_id)
            // Text can be set here 
            // but I believe setting MediaMetaData to MediaSession would be enough.
            // I havent tested it deeply yet but did display artist from session
            .setSmallIcon(R.drawable.your_drawable)
            .setContentTitle("your Content title")
            .setContentText("your content text")
            // set session here
            .setStyle(MediaStyleNotificationHelper.MediaStyle(session))
            // we don build.
    }

and finally if you want to update notification info yourself

you can do so by calling a function like this..

private fun updateNotification(/*parameter*/){

        nBuilder.setContentTitle("text") 
        nBuilder.setContentText("subtext")
        nManager.notify(NOTIFICATION_ID,nBuilder.build())
}