override fun onPrepareFromMediaId()

in common/src/main/java/com/example/android/uamp/media/MusicService.kt [493:519]


        override fun onPrepareFromMediaId(
            mediaId: String,
            playWhenReady: Boolean,
            extras: Bundle?
        ) {
            mediaSource.whenReady {
                val itemToPlay: MediaMetadataCompat? = mediaSource.find { item ->
                    item.id == mediaId
                }
                if (itemToPlay == null) {
                    Log.w(TAG, "Content not found: MediaID=$mediaId")
                    // TODO: Notify caller of the error.
                } else {

                    val playbackStartPositionMs =
                        extras?.getLong(MEDIA_DESCRIPTION_EXTRAS_START_PLAYBACK_POSITION_MS, C.TIME_UNSET)
                            ?: C.TIME_UNSET

                    preparePlaylist(
                        buildPlaylist(itemToPlay),
                        itemToPlay,
                        playWhenReady,
                        playbackStartPositionMs
                    )
                }
            }
        }