Les rappels de session multimédia appellent des méthodes dans plusieurs API pour contrôler le lecteur, gérer la priorité audio et communiquer avec la session multimédia et le service de navigateur multimédia. Notez que la logique MediaSession
qui répond aux rappels doit être cohérente. Le comportement du rappel ne doit pas dépendre de l'identité de l'appelant, qui peut être une activité dans la même application exécutant MediaSession
ou toute autre application avec un MediaController
connecté au MediaSession
.
Le tableau suivant récapitule la répartition de ces tâches entre les rappels.
onPlay(). | onPause() | onStop() | |
Focus audio | requestFocus() transmet votre OnAudioFocusChangeListener .Appelez toujours requestFocus() en premier, ne continuez que si le curseur est activé.
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abandonAudioFocus()
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Service | startService()
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stopSelf()
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Session multimédia | setActive(true)
- Mettre à jour les métadonnées et l'état |
- Mettre à jour les métadonnées et l'état | setActive(false)
- Mettre à jour les métadonnées et l'état |
Implémentation du lecteur | Lancer le lecteur | Mettre le lecteur en pause | Arrêter le lecteur |
Elle devient bruyante | Enregistrer votre BroadcastReceiver
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Annuler l'enregistrement de votre BroadcastReceiver
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Notifications | startForeground(notification)
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stopForeground(false)
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stopForeground(false)
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Voici un exemple de framework pour le rappel:
Kotlin
private val intentFilter = IntentFilter(ACTION_AUDIO_BECOMING_NOISY) // Defined elsewhere... private lateinit var afChangeListener: AudioManager.OnAudioFocusChangeListener private val myNoisyAudioStreamReceiver = BecomingNoisyReceiver() private lateinit var myPlayerNotification: MediaStyleNotification private lateinit var mediaSession: MediaSessionCompat private lateinit var service: MediaBrowserService private lateinit var player: SomeKindOfPlayer private lateinit var audioFocusRequest: AudioFocusRequest private val callback = object: MediaSessionCompat.Callback() { override fun onPlay() { val am = context.getSystemService(Context.AUDIO_SERVICE) as AudioManager // Request audio focus for playback, this registers the afChangeListener audioFocusRequest = AudioFocusRequest.Builder(AudioManager.AUDIOFOCUS_GAIN).run { setOnAudioFocusChangeListener(afChangeListener) setAudioAttributes(AudioAttributes.Builder().run { setContentType(AudioAttributes.CONTENT_TYPE_MUSIC) build() }) build() } val result = am.requestAudioFocus(audioFocusRequest) if (result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED) { // Start the service startService(Intent(context, MediaBrowserService::class.java)) // Set the session active (and update metadata and state) mediaSession.isActive = true // start the player (custom call) player.start() // Register BECOME_NOISY BroadcastReceiver registerReceiver(myNoisyAudioStreamReceiver, intentFilter) // Put the service in the foreground, post notification service.startForeground(id, myPlayerNotification) } } public override fun onStop() { val am = context.getSystemService(Context.AUDIO_SERVICE) as AudioManager // Abandon audio focus am.abandonAudioFocusRequest(audioFocusRequest) unregisterReceiver(myNoisyAudioStreamReceiver) // Stop the service service.stopSelf() // Set the session inactive (and update metadata and state) mediaSession.isActive = false // stop the player (custom call) player.stop() // Take the service out of the foreground service.stopForeground(false) } public override fun onPause() { val am = context.getSystemService(Context.AUDIO_SERVICE) as AudioManager // Update metadata and state // pause the player (custom call) player.pause() // unregister BECOME_NOISY BroadcastReceiver unregisterReceiver(myNoisyAudioStreamReceiver) // Take the service out of the foreground, retain the notification service.stopForeground(false) } }
Java
private IntentFilter intentFilter = new IntentFilter(AudioManager.ACTION_AUDIO_BECOMING_NOISY); // Defined elsewhere... private AudioManager.OnAudioFocusChangeListener afChangeListener; private BecomingNoisyReceiver myNoisyAudioStreamReceiver = new BecomingNoisyReceiver(); private MediaStyleNotification myPlayerNotification; private MediaSessionCompat mediaSession; private MediaBrowserService service; private SomeKindOfPlayer player; private AudioFocusRequest audioFocusRequest; MediaSessionCompat.Callback callback = new MediaSessionCompat.Callback() { @Override public void onPlay() { AudioManager am = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); // Request audio focus for playback, this registers the afChangeListener AudioAttributes attrs = new AudioAttributes.Builder() .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC) .build(); audioFocusRequest = new AudioFocusRequest.Builder(AudioManager.AUDIOFOCUS_GAIN) .setOnAudioFocusChangeListener(afChangeListener) .setAudioAttributes(attrs) .build(); int result = am.requestAudioFocus(audioFocusRequest); if (result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED) { // Start the service startService(new Intent(context, MediaBrowserService.class)); // Set the session active (and update metadata and state) mediaSession.setActive(true); // start the player (custom call) player.start(); // Register BECOME_NOISY BroadcastReceiver registerReceiver(myNoisyAudioStreamReceiver, intentFilter); // Put the service in the foreground, post notification service.startForeground(id, myPlayerNotification); } } @Override public void onStop() { AudioManager am = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); // Abandon audio focus am.abandonAudioFocusRequest(audioFocusRequest); unregisterReceiver(myNoisyAudioStreamReceiver); // Stop the service service.stopSelf(); // Set the session inactive (and update metadata and state) mediaSession.setActive(false); // stop the player (custom call) player.stop(); // Take the service out of the foreground service.stopForeground(false); } @Override public void onPause() { AudioManager am = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); // Update metadata and state // pause the player (custom call) player.pause(); // unregister BECOME_NOISY BroadcastReceiver unregisterReceiver(myNoisyAudioStreamReceiver); // Take the service out of the foreground, retain the notification service.stopForeground(false); } };