永远不会调用MediaSession回调

Question

我用一个activity创建了一个简单的应用程序，并在它的onCreate方法中创建了一个MediaSession

但是，当我运行应用程序并使用外部媒体按钮时，回调永远不会被调用。你知道我可能遗漏了什么吗？

override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        this.mediaSession = MediaSessionCompat(this, "TAG")
        this.mediaSession?.setCallback(object : MediaSessionCompat.Callback() {
            override fun onMediaButtonEvent(mediaButtonIntent: Intent): Boolean {
                return super.onMediaButtonEvent(mediaButtonIntent)
            }
            override fun onPlay() {
                super.onPlay()
            }
        })
        val builder = PlaybackStateCompat.Builder()
        builder.setActions(PlaybackStateCompat.ACTION_PLAY)
        builder.setState(PlaybackStateCompat.STATE_STOPPED, PlaybackStateCompat.PLAYBACK_POSITION_UNKNOWN, 0.0f)
        this.mediaSession?.setPlaybackState(builder.build())
        this.mediaSession?.setFlags(MediaSessionCompat.FLAG_HANDLES_MEDIA_BUTTONS or MediaSessionCompat.FLAG_HANDLES_TRANSPORT_CONTROLS)
        this.mediaSession?.isActive = true
    }

Answer 1

您需要实现BroadcastReceiver。这里有一个例子：https://github.com/tutsplus/background-audio-in-android-with-mediasessioncompat/blob/master/app/src/main/java/com/tutsplus/backgroundaudio/BackgroundAudioService.java