55th MAD RSC

THE PREPARE NOTE

Media PlayBack with service

App Class

class App : Application() {
    @RequiresApi(Build.VERSION_CODES.O)
    override fun onCreate() {
        super.onCreate()
        createChannel()
        updateWidget()
        startForegroundService(Intent(this, PlaybackService::class.java))
    }

    private fun updateWidget() {
        val appScope = CoroutineScope(SupervisorJob() + Dispatchers.Main)
        appScope.launch {
            Widget().updateAll(applicationContext)
        }
    }

    @RequiresApi(Build.VERSION_CODES.O)
    private fun createChannel() {
        val channel = NotificationChannel(
            "media_channel",
            "Media Channel",
            NotificationManager.IMPORTANCE_LOW
        )
        NotificationManagerCompat.from(this).createNotificationChannel(channel) }
}

Manifest

<service
         android:name=".PlaybackService"
         android:exported="true"
         android:foregroundServiceType="mediaPlayback">
    <intent-filter>
        <action android:name="androidx.media3.session.MediaSessionService" />
    </intent-filter>
</service>

Service

data class PlayerState(
    var currentPosition: Long = 0L,
    var duration: Long = 1000L,
    var isPlaying: Boolean = false,
    var volume: Float = 1.0f,
    var currentIndex: Int = 0,
    var repeatMode: Int = Player.REPEAT_MODE_OFF,
    var metadata: MediaMetadata = MediaMetadata.Builder().build(),
    var isStarted: Boolean = false,
)

class PlaybackService : MediaSessionService() {
    private var isForegroundStarted = false
    private var mediaSession: MediaSession? = null
    private lateinit var player: ExoPlayer
    private val serviceScope = CoroutineScope(Dispatchers.Main + Job())
    private var controllerJob: Job? = null

    companion object {
        private val _playerState = MutableStateFlow(PlayerState())
        val playerState: StateFlow<PlayerState> = _playerState

        var playerInstance: ExoPlayer? = null

        fun init(items: List<MediaItem>) {
            playerInstance?.apply {
                setMediaItems(items)
                prepare()
                play()
            }
        }
    }

    override fun onCreate() {
        super.onCreate()
        player = ExoPlayer.Builder(this).build()
        playerInstance = player
        player.addListener(object : Player.Listener {
            override fun onEvents(player: Player, events: Player.Events) {
                _playerState.value = _playerState.value.copy(
                    currentIndex = player.currentMediaItemIndex,
                    isPlaying = player.isPlaying,
                    duration = player.duration,
                    volume = player.volume,
                    repeatMode = player.repeatMode,
                    metadata = player.mediaMetadata
                )
                serviceScope.launch {
                    Widget().updateAll(applicationContext)
                }
                super.onEvents(player, events)
            }
        })

        mediaSession = MediaSession.Builder(this, player).build()
        startControllerConnection()
    }

    private fun startControllerConnection() {
        controllerJob?.cancel()
        controllerJob = CoroutineScope(Dispatchers.Main).launch {
            val sessionToken = SessionToken(
                this@PlaybackService,
                ComponentName(this@PlaybackService, PlaybackService::class.java)
            )
            MediaController.Builder(this@PlaybackService, sessionToken).buildAsync()
        }
    }

    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        super.onStartCommand(intent, flags, startId)
        if (!isForegroundStarted) {
            val notification = createNotification()
            startForeground(1, notification)
            isForegroundStarted = true
        }
        return START_STICKY
    }

    override fun onGetSession(controllerInfo: MediaSession.ControllerInfo): MediaSession? {
        return mediaSession
    }

    override fun onDestroy() {
        mediaSession?.run {
            player.release()
            release()
        }
        playerInstance = null
        super.onDestroy()
    }

    private fun createNotification(): Notification {
        return NotificationCompat.Builder(this, "media_channel")
            .setSmallIcon(android.R.drawable.ic_media_play)
            .setContentTitle("title")
            .setContentText("text")
            .setOngoing(true)
            .build()
    }
}

for press the notification to open the app

  mediaSession = MediaSession.Builder(this, player)
            .setSessionActivity(pendingIntent)
            .build()