Addressed review comments

app/src/main/java/org/schabi/newpipe/fragments/detail/VideoDetailFragment.java

@@ -229,6 +229,7 @@ public final class VideoDetailFragment
     private ContentObserver settingsContentObserver;
     @Nullable
     private PlayerService playerService;
+    @Nullable
     private Player player;
     private final PlayerHolder playerHolder = PlayerHolder.getInstance();
 
@@ -236,7 +237,7 @@ public final class VideoDetailFragment
     // Service management
     //////////////////////////////////////////////////////////////////////////*/
     @Override
-    public void onServiceConnected(final Player connectedPlayer,
+    public void onServiceConnected(@Nullable final Player connectedPlayer,
                                    final PlayerService connectedPlayerService,
                                    final boolean playAfterConnect) {
         player = connectedPlayer;

app/src/main/java/org/schabi/newpipe/local/dialog/PlaylistDialog.java

@@ -163,7 +163,7 @@ public abstract class PlaylistDialog extends DialogFragment implements StateSave
      * @return the disposable that was created
      */
     public static Disposable showForPlayQueue(
-            final Player player,
+            @NonNull final Player player,
             @NonNull final FragmentManager fragmentManager) {
 
         final List<StreamEntity> streamEntities = Stream.of(player.getPlayQueue())

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

@@ -61,6 +61,7 @@ public final class PlayQueueActivity extends AppCompatActivity
 
     private static final int MENU_ID_AUDIO_TRACK = 71;
 
+    @Nullable
     private Player player;
 
     private boolean serviceBound;
@@ -137,30 +138,38 @@ public final class PlayQueueActivity extends AppCompatActivity
                 NavigationHelper.openSettings(this);
                 return true;
             case R.id.action_append_playlist:
+                if (player != null) {
                     PlaylistDialog.showForPlayQueue(player, getSupportFragmentManager());
+                }
                 return true;
             case R.id.action_playback_speed:
                 openPlaybackParameterDialog();
                 return true;
             case R.id.action_mute:
+                if (player != null) {
                     player.toggleMute();
+                }
                 return true;
             case R.id.action_system_audio:
                 startActivity(new Intent(Settings.ACTION_SOUND_SETTINGS));
                 return true;
             case R.id.action_switch_main:
+                if (player != null) {
                     this.player.setRecovery();
                     NavigationHelper.playOnMainPlayer(this, player.getPlayQueue(), true);
+                }
                 return true;
             case R.id.action_switch_popup:
-                if (PermissionHelper.isPopupEnabledElseAsk(this)) {
+                if (PermissionHelper.isPopupEnabledElseAsk(this) && player != null) {
                     this.player.setRecovery();
                     NavigationHelper.playOnPopupPlayer(this, player.getPlayQueue(), true);
                 }
                 return true;
             case R.id.action_switch_background:
+                if (player != null) {
                     this.player.setRecovery();
                     NavigationHelper.playOnBackgroundPlayer(this, player.getPlayQueue(), true);
+                }
                 return true;
         }
 
@@ -309,7 +318,7 @@ public final class PlayQueueActivity extends AppCompatActivity
 
             @Override
             public void onSwiped(final int index) {
-                if (index != -1) {
+                if (index != -1 && player != null) {
                     player.getPlayQueue().remove(index);
                 }
             }
@@ -659,7 +668,7 @@ public final class PlayQueueActivity extends AppCompatActivity
      * @param itemId index of the selected item
      */
     private void onAudioTrackClick(final int itemId) {
-        if (player.getCurrentMetadata() == null) {
+        if (player == null || player.getCurrentMetadata() == null) {
             return;
         }
         player.getCurrentMetadata().getMaybeAudioTrack().ifPresent(audioTrack -> {

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

@@ -46,8 +46,7 @@ class PlayerService : MediaBrowserServiceCompat() {
             loading stream metadata) takes a lot of time, the app would crash on Android 8+ as the
             service would never be put in the foreground while we said to the system we would do so
              */
-            UIs()
+            UIs()[NotificationPlayerUi::class.java]
-                .get(NotificationPlayerUi::class.java)
                 .ifPresent { it.createNotificationAndStartForeground() }
         }
     }
@@ -198,10 +197,7 @@ class PlayerService : MediaBrowserServiceCompat() {
     ) : Binder() {
         private val playerService = WeakReference(playerService)
 
-        val service: PlayerService?
+        fun getPlayer(): Player? = playerService.get()?.player
-            get() = playerService.get()
-
-        fun getPlayer(): Player = service?.player ?: throw Error("Player service is null")
     }
 
     companion object {

app/src/main/java/org/schabi/newpipe/player/event/PlayerServiceExtendedEventListener.java

@@ -1,10 +1,12 @@
 package org.schabi.newpipe.player.event;
 
+import androidx.annotation.Nullable;
+
 import org.schabi.newpipe.player.PlayerService;
 import org.schabi.newpipe.player.Player;
 
 public interface PlayerServiceExtendedEventListener extends PlayerServiceEventListener {
-    void onServiceConnected(Player player,
+    void onServiceConnected(@Nullable Player player,
                             PlayerService playerService,
                             boolean playAfterConnect);
     void onServiceDisconnected();

app/src/main/java/org/schabi/newpipe/player/helper/PlayerHolder.java

@@ -166,7 +166,7 @@ public final class PlayerHolder {
             }
             final PlayerService.LocalBinder localBinder = (PlayerService.LocalBinder) service;
 
-            playerService = localBinder.getService();
+            playerService = localBinder.getPlayer().getService();
             player = localBinder.getPlayer();
             if (listener != null) {
                 listener.onServiceConnected(player, playerService, playAfterConnect);

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

@@ -59,7 +59,9 @@ import org.schabi.newpipe.util.NavigationHelper
 import org.schabi.newpipe.util.ServiceHelper
 import java.util.stream.Collectors
 
-class MediaBrowserConnector(private val playerService: PlayerService) : PlaybackPreparer {
+class MediaBrowserConnector(
+    private val playerService: PlayerService,
+) : PlaybackPreparer {
     private val mediaSession = MediaSessionCompat(playerService, TAG)
     val sessionConnector = MediaSessionConnector(mediaSession).apply {
         setMetadataDeduplicationEnabled(true)
@@ -627,7 +629,10 @@ class MediaBrowserConnector(private val playerService: PlayerService) : Playback
     private fun handleSearchError(throwable: Throwable) {
         Log.e(TAG, "Search error: $throwable")
         disposePrepareOrPlayCommands()
-        playbackError(R.string.content_not_supported, PlaybackStateCompat.ERROR_CODE_NOT_SUPPORTED)
+        sessionConnector.setCustomErrorMessage(
+            playerService.getString(R.string.search_no_results),
+            PlaybackStateCompat.ERROR_CODE_APP_ERROR,
+        )
     }
 
     override fun onPrepareFromUri(