Android
MediaSession

Syntax

• void mediaSessionCompat.setFlags (Int Flags)
• void mediaSessionCompat.setMediaButtonReceiver (PendingIntent mbr)
• void mediaSessionCompat.setCallback (Rückruf von MediaSessionCompat.Callback)
• void mediaSessionCompat.setActive (boolean aktiv)
• MediaSessionCompat.Token mediaSessionCompat.getSessionToken ()
• void mediaSessionCompat.release ()
• void mediaSessionCompat.setPlaybackState (PlaybackStateCompat-Status)
• void mediaSessionCompat.setMetadata (Metadaten von MediaMetadataCompat)

Bemerkungen

Schaltflächenereignisse empfangen und bearbeiten

In diesem Beispiel wird ein MediaSession Objekt erstellt, wenn ein Service gestartet wird. Das MediaSession Objekt wird freigegeben, wenn der Service zerstört wird:

public final class MyService extends Service {
    private static MediaSession s_mediaSession;

    @Override
    public void onCreate() {
        // Instantiate new MediaSession object.
        configureMediaSession();
    }

    @Override
    public void onDestroy() {
        if (s_mediaSession != null)
            s_mediaSession.release();
    }
}

Die folgende Methode instanziiert und konfiguriert die MediaSession der MediaSession Schaltfläche:

private void configureMediaSession {
    s_mediaSession = new MediaSession(this, "MyMediaSession");

    // Overridden methods in the MediaSession.Callback class.
    s_mediaSession.setCallback(new MediaSession.Callback() {
        @Override
        public boolean onMediaButtonEvent(Intent mediaButtonIntent) {
            Log.d(TAG, "onMediaButtonEvent called: " + mediaButtonIntent);
            KeyEvent ke = mediaButtonIntent.getParcelableExtra(Intent.EXTRA_KEY_EVENT);
            if (ke != null && ke.getAction() == KeyEvent.ACTION_DOWN) {
                int keyCode = ke.getKeyCode();
                Log.d(TAG, "onMediaButtonEvent Received command: " + ke);
            }
            return super.onMediaButtonEvent(mediaButtonIntent);
        }

        @Override
        public void onSkipToNext() {
            Log.d(TAG, "onSkipToNext called (media button pressed)");
            Toast.makeText(getApplicationContext(), "onSkipToNext called", Toast.LENGTH_SHORT).show();
            skipToNextPlaylistItem(); // Handle this button press.
            super.onSkipToNext();
        }

        @Override
        public void onSkipToPrevious() {
            Log.d(TAG, "onSkipToPrevious called (media button pressed)");
            Toast.makeText(getApplicationContext(), "onSkipToPrevious called", Toast.LENGTH_SHORT).show();
            skipToPreviousPlaylistItem(); // Handle this button press.
            super.onSkipToPrevious();
        }

        @Override
        public void onPause() {
            Log.d(TAG, "onPause called (media button pressed)");
            Toast.makeText(getApplicationContext(), "onPause called", Toast.LENGTH_SHORT).show();
            mpPause(); // Pause the player.
            super.onPause();
        }

        @Override
        public void onPlay() {
            Log.d(TAG, "onPlay called (media button pressed)");
            mpStart(); // Start player/playback.
            super.onPlay();
        }

        @Override
        public void onStop() {
            Log.d(TAG, "onStop called (media button pressed)");
            mpReset(); // Stop and/or reset the player.
            super.onStop();
        }
    });

    s_mediaSession.setFlags(MediaSession.FLAG_HANDLES_MEDIA_BUTTONS | MediaSession.FLAG_HANDLES_TRANSPORT_CONTROLS);
    s_mediaSession.setActive(true);
}

Die folgende Methode sendet Metadaten (in einer HashMap gespeichert) über A2DP an das Gerät:

void sendMetaData(@NonNull final HashMap<String, String> hm) {
    // Return if Bluetooth A2DP is not in use.
    if (!((AudioManager) getSystemService(Context.AUDIO_SERVICE)).isBluetoothA2dpOn()) return;

    MediaMetadata metadata = new MediaMetadata.Builder()
            .putString(MediaMetadata.METADATA_KEY_TITLE, hm.get("Title"))
            .putString(MediaMetadata.METADATA_KEY_ALBUM, hm.get("Album"))
            .putString(MediaMetadata.METADATA_KEY_ARTIST, hm.get("Artist"))
            .putString(MediaMetadata.METADATA_KEY_AUTHOR, hm.get("Author"))
            .putString(MediaMetadata.METADATA_KEY_COMPOSER, hm.get("Composer"))
            .putString(MediaMetadata.METADATA_KEY_WRITER, hm.get("Writer"))
            .putString(MediaMetadata.METADATA_KEY_DATE, hm.get("Date"))
            .putString(MediaMetadata.METADATA_KEY_GENRE, hm.get("Genre"))
            .putLong(MediaMetadata.METADATA_KEY_YEAR, tryParse(hm.get("Year")))
            .putLong(MediaMetadata.METADATA_KEY_DURATION, tryParse(hm.get("Raw Duration")))
            .putLong(MediaMetadata.METADATA_KEY_TRACK_NUMBER, tryParse(hm.get("Track Number")))
            .build();

    s_mediaSession.setMetadata(metadata);
}

Die folgende Methode legt den PlaybackState . Außerdem wird festgelegt, auf welche MediaSession die MediaSession reagiert:

private void setPlaybackState(@NonNull final int stateValue) {
    PlaybackState state = new PlaybackState.Builder()
            .setActions(PlaybackState.ACTION_PLAY | PlaybackState.ACTION_SKIP_TO_NEXT
                    | PlaybackState.ACTION_PAUSE | PlaybackState.ACTION_SKIP_TO_PREVIOUS
                    | PlaybackState.ACTION_STOP | PlaybackState.ACTION_PLAY_PAUSE)
            .setState(stateValue, PlaybackState.PLAYBACK_POSITION_UNKNOWN, 0)
            .build();

    s_mediaSession.setPlaybackState(state);
}