Keep MediaSessionCompat and MediaSessionConnector in a separate class

These objects need to live beyond the player for supporting
MediaBrowserServiceCompat and Android Auto, so they need to move outside
of the MediaSessionPlayerUi class.

app/src/main/java/org/schabi/newpipe/player/Player.java

@@ -302,7 +302,7 @@ public final class Player implements PlaybackListener, Listener {
         // notification ui in the UIs list, since the notification depends on the media session in
         // PlayerUi#initPlayer(), and UIs.call() guarantees UI order is preserved.
         UIs = new PlayerUiList(
-                new MediaSessionPlayerUi(this),
+                new MediaSessionPlayerUi(this, service.getSessionConnector()),
                 new NotificationPlayerUi(this)
         );
     }

app/src/main/java/org/schabi/newpipe/player/PlayerService.java

@@ -28,6 +28,9 @@ import android.os.Binder;
 import android.os.IBinder;
 import android.util.Log;
 
+import com.google.android.exoplayer2.ext.mediasession.MediaSessionConnector;
+
+import org.schabi.newpipe.player.mediabrowser.MediaBrowserConnector;
 import org.schabi.newpipe.player.mediasession.MediaSessionPlayerUi;
 import org.schabi.newpipe.player.notification.NotificationPlayerUi;
 import org.schabi.newpipe.util.ThemeHelper;
@@ -47,6 +50,9 @@ public final class PlayerService extends Service {
     private final IBinder mBinder = new PlayerService.LocalBinder(this);
 
 
+    private MediaBrowserConnector mediaBrowserConnector;
+
+
     /*//////////////////////////////////////////////////////////////////////////
     // Service's LifeCycle
     //////////////////////////////////////////////////////////////////////////*/
@@ -59,6 +65,11 @@ public final class PlayerService extends Service {
         assureCorrectAppLanguage(this);
         ThemeHelper.setTheme(this);
 
+        mediaBrowserConnector = new MediaBrowserConnector(this);
+    }
+
+    private void initializePlayer() {
+        if (player == null) {
             player = new Player(this);
             /*
             Create the player notification and start immediately the service in foreground,
@@ -69,6 +80,7 @@ public final class PlayerService extends Service {
             player.UIs().get(NotificationPlayerUi.class)
                     .ifPresent(NotificationPlayerUi::createNotificationAndStartForeground);
         }
+    }
 
     @Override
     public int onStartCommand(final Intent intent, final int flags, final int startId) {
@@ -104,11 +116,10 @@ public final class PlayerService extends Service {
             return START_NOT_STICKY;
         }
 
-        if (player != null) {
+        initializePlayer();
         player.handleIntent(intent);
         player.UIs().get(MediaSessionPlayerUi.class)
                 .ifPresent(ui -> ui.handleMediaButtonIntent(intent));
-        }
 
         return START_NOT_STICKY;
     }
@@ -143,6 +154,10 @@ public final class PlayerService extends Service {
             Log.d(TAG, "destroy() called");
         }
         cleanup();
+        if (mediaBrowserConnector != null) {
+            mediaBrowserConnector.release();
+            mediaBrowserConnector = null;
+        }
     }
 
     private void cleanup() {
@@ -167,6 +182,9 @@ public final class PlayerService extends Service {
         return mBinder;
     }
 
+    public MediaSessionConnector getSessionConnector() {
+        return mediaBrowserConnector.getSessionConnector();
+    }
     public static class LocalBinder extends Binder {
         private final WeakReference<PlayerService> playerService;
 

app/src/main/java/org/schabi/newpipe/player/mediabrowser/MediaBrowserConnector.java

@@ -0,0 +1,32 @@
+package org.schabi.newpipe.player.mediabrowser;
+
+import android.support.v4.media.session.MediaSessionCompat;
+
+import androidx.annotation.NonNull;
+
+import com.google.android.exoplayer2.ext.mediasession.MediaSessionConnector;
+
+import org.schabi.newpipe.player.PlayerService;
+
+public class MediaBrowserConnector {
+    private static final String TAG = MediaBrowserConnector.class.getSimpleName();
+
+    private final PlayerService playerService;
+    private final @NonNull MediaSessionConnector sessionConnector;
+    private final @NonNull MediaSessionCompat mediaSession;
+
+    public MediaBrowserConnector(@NonNull final PlayerService playerService) {
+        this.playerService = playerService;
+        mediaSession = new MediaSessionCompat(playerService, TAG);
+        sessionConnector = new MediaSessionConnector(mediaSession);
+        sessionConnector.setMetadataDeduplicationEnabled(true);
+    }
+
+    public @NonNull MediaSessionConnector getSessionConnector() {
+        return sessionConnector;
+    }
+
+    public void release() {
+        mediaSession.release();
+    }
+}

app/src/main/java/org/schabi/newpipe/player/mediasession/MediaSessionPlayerUi.java

@@ -50,8 +50,11 @@ public class MediaSessionPlayerUi extends PlayerUi
     private List<NotificationActionData> prevNotificationActions = List.of();
 
 
-    public MediaSessionPlayerUi(@NonNull final Player player) {
+    public MediaSessionPlayerUi(@NonNull final Player player,
+                                @NonNull final MediaSessionConnector sessionConnector) {
         super(player);
+        this.mediaSession = sessionConnector.mediaSession;
+        this.sessionConnector = sessionConnector;
         ignoreHardwareMediaButtonsKey =
                 context.getString(R.string.ignore_hardware_media_buttons_key);
     }
@@ -61,10 +64,8 @@ public class MediaSessionPlayerUi extends PlayerUi
         super.initPlayer();
         destroyPlayer(); // release previously used resources
 
-        mediaSession = new MediaSessionCompat(context, TAG);
         mediaSession.setActive(true);
 
-        sessionConnector = new MediaSessionConnector(mediaSession);
         sessionConnector.setQueueNavigator(new PlayQueueNavigator(mediaSession, player));
         sessionConnector.setPlayer(getForwardingPlayer());
 
@@ -77,7 +78,6 @@ public class MediaSessionPlayerUi extends PlayerUi
         updateShouldIgnoreHardwareMediaButtons(player.getPrefs());
         player.getPrefs().registerOnSharedPreferenceChangeListener(this);
 
-        sessionConnector.setMetadataDeduplicationEnabled(true);
         sessionConnector.setMediaMetadataProvider(exoPlayer -> buildMediaMetadata());
 
         // force updating media session actions by resetting the previous ones
@@ -89,28 +89,24 @@ public class MediaSessionPlayerUi extends PlayerUi
     public void destroyPlayer() {
         super.destroyPlayer();
         player.getPrefs().unregisterOnSharedPreferenceChangeListener(this);
-        if (sessionConnector != null) {
+
         sessionConnector.setMediaButtonEventHandler(null);
         sessionConnector.setPlayer(null);
         sessionConnector.setQueueNavigator(null);
-            sessionConnector = null;
-        }
-        if (mediaSession != null) {
+        sessionConnector.setMediaMetadataProvider(null);
+
         mediaSession.setActive(false);
-            mediaSession.release();
-            mediaSession = null;
-        }
+
         prevNotificationActions = List.of();
     }
 
     @Override
     public void onThumbnailLoaded(@Nullable final Bitmap bitmap) {
         super.onThumbnailLoaded(bitmap);
-        if (sessionConnector != null) {
+
         // the thumbnail is now loaded: invalidate the metadata to trigger a metadata update
         sessionConnector.invalidateMediaSessionMetadata();
     }
-    }
 
 
     @Override
@@ -132,7 +128,7 @@ public class MediaSessionPlayerUi extends PlayerUi
     }
 
     public Optional<MediaSessionCompat.Token> getSessionToken() {
-        return Optional.ofNullable(mediaSession).map(MediaSessionCompat::getSessionToken);
+        return Optional.of(mediaSession.getSessionToken());
     }