Erstelle ein MediaSession
, wenn deine App die Wiedergabe von Medien vorbereitet. Das folgende Code-Snippet ist ein Beispiel dafür, wie der entsprechende Callback und die Flags festgelegt werden:
Kotlin
session = MediaSession(this, "MusicService").apply { setCallback(MediaSessionCallback()) setFlags( MediaSession.FLAG_HANDLES_MEDIA_BUTTONS or MediaSession.FLAG_HANDLES_TRANSPORT_CONTROLS ) }
Java
session = new MediaSession(this, "MusicService"); session.setCallback(new MediaSessionCallback()); session.setFlags(MediaSession.FLAG_HANDLES_MEDIA_BUTTONS | MediaSession.FLAG_HANDLES_TRANSPORT_CONTROLS);
Mediensitzung starten
Rufen Sie auch setActive(true)
auf, wenn die Wiedergabe beginnt. Ihre App muss außerdem den Audiofokus anfordern, wie unter Audiofokus verwalten beschrieben. Diese Schritte werden im folgenden Beispiel gezeigt:
Kotlin
private fun handlePlayRequest() { tryToGetAudioFocus() if (!session.isActive) { session.isActive = true } ... }
Java
private void handlePlayRequest() { tryToGetAudioFocus(); if (!session.isActive()) { session.setActive(true); } ... }
Wiedergabestatus aktualisieren
Aktualisieren Sie den Wiedergabestatus in MediaSession
, um den Status des aktuellen Mediums widerzuspiegeln:
Kotlin
private fun updatePlaybackState() { val position: Long = mediaPlayer ?.takeIf { it.isPlaying } ?.currentPosition?.toLong() ?: PlaybackState.PLAYBACK_POSITION_UNKNOWN val stateBuilder = PlaybackState.Builder() .setActions(getAvailableActions()).apply { setState(mState, position, 1.0f) } session.setPlaybackState(stateBuilder.build()) } private fun getAvailableActions(): Long { var actions = (PlaybackState.ACTION_PLAY_PAUSE or PlaybackState.ACTION_PLAY_FROM_MEDIA_ID or PlaybackState.ACTION_PLAY_FROM_SEARCH) playingQueue?.takeIf { it.isNotEmpty() }?.apply { actions = if (mState == PlaybackState.STATE_PLAYING) { actions or PlaybackState.ACTION_PAUSE } else { actions or PlaybackState.ACTION_PLAY } if (currentIndexOnQueue > 0) { actions = actions or PlaybackState.ACTION_SKIP_TO_PREVIOUS } if (currentIndexOnQueue < size - 1) { actions = actions or PlaybackState.ACTION_SKIP_TO_NEXT } } return actions }
Java
private void updatePlaybackState() { long position = PlaybackState.PLAYBACK_POSITION_UNKNOWN; if (mediaPlayer != null && mediaPlayer.isPlaying()) { position = mediaPlayer.getCurrentPosition(); } PlaybackState.Builder stateBuilder = new PlaybackState.Builder() .setActions(getAvailableActions()); stateBuilder.setState(mState, position, 1.0f); session.setPlaybackState(stateBuilder.build()); } private long getAvailableActions() { long actions = PlaybackState.ACTION_PLAY_PAUSE | PlaybackState.ACTION_PLAY_FROM_MEDIA_ID | PlaybackState.ACTION_PLAY_FROM_SEARCH; if (playingQueue == null || playingQueue.isEmpty()) { return actions; } if (mState == PlaybackState.STATE_PLAYING) { actions |= PlaybackState.ACTION_PAUSE; } else { actions |= PlaybackState.ACTION_PLAY; } if (currentIndexOnQueue > 0) { actions |= PlaybackState.ACTION_SKIP_TO_PREVIOUS; } if (currentIndexOnQueue < playingQueue.size() - 1) { actions |= PlaybackState.ACTION_SKIP_TO_NEXT; } return actions; }
Medienmetadaten aktualisieren
Legen Sie MediaMetadata
mit der Methode setMetadata()
fest. Diese Methode wird nur einmal pro wiedergegebenem Objekt aufgerufen. Damit können Sie der Mediensitzung Informationen über die Medien zur Verfügung stellen, einschließlich Titel, Untertitel, Künstler, Artwork usw. Das folgende Beispiel ist auf Musik ausgerichtet und setzt voraus, dass die Daten des Titels in der benutzerdefinierten Datenklasse MediaData
gespeichert sind:
Kotlin
private fun updateMetadata(myData: MediaData) { val metadataBuilder = MediaMetadata.Builder().apply { // To provide most control over how an item is displayed set the // display fields in the metadata putString(MediaMetadata.METADATA_KEY_DISPLAY_TITLE, myData.displayTitle) putString(MediaMetadata.METADATA_KEY_DISPLAY_SUBTITLE, myData.displaySubtitle) putString(MediaMetadata.METADATA_KEY_DISPLAY_ICON_URI, myData.artUri) // And at minimum the title and artist for legacy support putString(MediaMetadata.METADATA_KEY_TITLE, myData.title) putString(MediaMetadata.METADATA_KEY_ARTIST, myData.artist) // A small bitmap for the artwork is also recommended putBitmap(MediaMetadata.METADATA_KEY_ART, myData.artBitmap) // Add any other fields you have for your data as well } session.setMetadata(metadataBuilder.build()) }
Java
private void updateMetadata(MediaData myData) { MediaMetadata.Builder metadataBuilder = new MediaMetadata.Builder(); // To provide most control over how an item is displayed set the // display fields in the metadata metadataBuilder.putString(MediaMetadata.METADATA_KEY_DISPLAY_TITLE, myData.displayTitle); metadataBuilder.putString(MediaMetadata.METADATA_KEY_DISPLAY_SUBTITLE, myData.displaySubtitle); metadataBuilder.putString(MediaMetadata.METADATA_KEY_DISPLAY_ICON_URI, myData.artUri); // And at minimum the title and artist for legacy support metadataBuilder.putString(MediaMetadata.METADATA_KEY_TITLE, myData.title); metadataBuilder.putString(MediaMetadata.METADATA_KEY_ARTIST, myData.artist); // A small bitmap for the artwork is also recommended metadataBuilder.putBitmap(MediaMetadata.METADATA_KEY_ART, myData.artBitmap); // Add any other fields you have for your data as well session.setMetadata(metadataBuilder.build()); }