remove empty song placeholder and fix related null errors

app/src/main/java/com/dkanada/gramophone/adapter/song/AbsOffsetSongAdapter.java

@@ -90,7 +90,7 @@ public abstract class AbsOffsetSongAdapter extends SongAdapter {
         @Override
         protected Song getSong() {
             // return empty song just to be safe
-            if (getItemViewType() == OFFSET_ITEM) return Song.EMPTY;
+            if (getItemViewType() == OFFSET_ITEM) return null;
             return dataSet.get(getBindingAdapterPosition() - 1);
         }
 

app/src/main/java/com/dkanada/gramophone/fragments/player/MiniPlayerFragment.java

@@ -15,6 +15,7 @@ import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
 import com.dkanada.gramophone.databinding.FragmentMiniPlayerBinding;
+import com.dkanada.gramophone.model.Song;
 import com.kabouzeid.appthemehelper.ThemeStore;
 import com.kabouzeid.appthemehelper.util.ATHUtil;
 import com.dkanada.gramophone.R;
@@ -69,7 +70,10 @@ public class MiniPlayerFragment extends AbsMusicServiceFragment implements Music
     }
 
     private void updateSongTitle() {
-        binding.miniPlayerTitle.setText(MusicPlayerRemote.getCurrentSong().title);
+        Song song = MusicPlayerRemote.getCurrentSong();
+        if (song != null) {
+            binding.miniPlayerTitle.setText(song.title);
+        }
     }
 
     @Override

app/src/main/java/com/dkanada/gramophone/fragments/player/card/CardPlayerFragment.java

@@ -143,6 +143,8 @@ public class CardPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
 
     @Override
     public void onServiceConnected() {
+        if (MusicPlayerRemote.getCurrentSong() == null) return;
+
         updateQueue();
         updateCurrentSong();
         updateIsFavorite();
@@ -150,6 +152,8 @@ public class CardPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
 
     @Override
     public void onPlayMetadataChanged() {
+        if (MusicPlayerRemote.getCurrentSong() == null) return;
+
         updateCurrentSong();
         updateIsFavorite();
         updateQueuePosition();
@@ -329,6 +333,7 @@ public class CardPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
         void setUpPanelAndAlbumCoverHeight();
     }
 
+    @SuppressWarnings("ConstantConditions")
     private static abstract class BaseImpl implements Impl {
         protected CardPlayerFragment fragment;
         protected FragmentCardPlayerBinding binding;
@@ -341,7 +346,6 @@ public class CardPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
         public AnimatorSet createDefaultColorChangeAnimatorSet(int newColor) {
             Animator backgroundAnimator;
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
-                // noinspection ConstantConditions
                 int x = (int) (fragment.playbackControlsFragment.binding.playerPlayPauseFab.getX() + fragment.playbackControlsFragment.binding.playerPlayPauseFab.getWidth() / 2 + fragment.playbackControlsFragment.getView().getX());
                 int y = (int) (fragment.playbackControlsFragment.binding.playerPlayPauseFab.getY() + fragment.playbackControlsFragment.binding.playerPlayPauseFab.getHeight() / 2 + fragment.playbackControlsFragment.getView().getY() + fragment.playbackControlsFragment.binding.playerProgressSlider.getHeight());
                 float startRadius = Math.max(fragment.playbackControlsFragment.binding.playerPlayPauseFab.getWidth() / 2, fragment.playbackControlsFragment.binding.playerPlayPauseFab.getHeight() / 2);
@@ -378,7 +382,7 @@ public class CardPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
     @SuppressWarnings("ConstantConditions")
     private static class PortraitImpl extends BaseImpl {
         MediaEntryViewHolder currentSongViewHolder;
-        Song currentSong = Song.EMPTY;
+        Song currentSong;
 
         public PortraitImpl(CardPlayerFragment fragment, FragmentCardPlayerBinding binding) {
             super(fragment, binding);
@@ -394,7 +398,6 @@ public class CardPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
             currentSongViewHolder.image.setColorFilter(ATHUtil.resolveColor(fragment.getActivity(), R.attr.iconColor, ThemeStore.textColorSecondary(fragment.getActivity())), PorterDuff.Mode.SRC_IN);
             currentSongViewHolder.image.setImageResource(R.drawable.ic_volume_up_white_24dp);
             currentSongViewHolder.itemView.setOnClickListener(v -> {
-                // toggle the panel
                 if (binding.playerSlidingLayout.getPanelState() == SlidingUpPanelLayout.PanelState.COLLAPSED) {
                     binding.playerSlidingLayout.setPanelState(SlidingUpPanelLayout.PanelState.EXPANDED);
                 } else if (binding.playerSlidingLayout.getPanelState() == SlidingUpPanelLayout.PanelState.EXPANDED) {

app/src/main/java/com/dkanada/gramophone/fragments/player/flat/FlatPlayerFragment.java

@@ -143,6 +143,8 @@ public class FlatPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
 
     @Override
     public void onServiceConnected() {
+        if (MusicPlayerRemote.getCurrentSong() == null) return;
+
         updateQueue();
         updateCurrentSong();
         updateIsFavorite();
@@ -150,6 +152,8 @@ public class FlatPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
 
     @Override
     public void onPlayMetadataChanged() {
+        if (MusicPlayerRemote.getCurrentSong() == null) return;
+
         updateCurrentSong();
         updateIsFavorite();
         updateQueuePosition();
@@ -225,8 +229,8 @@ public class FlatPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
         Drawable drawable = ImageUtil.getTintedVectorDrawable(requireActivity(), res, color);
 
         binding.playerToolbar.getMenu().findItem(R.id.action_toggle_favorite)
-                .setIcon(drawable)
+            .setIcon(drawable)
-                .setTitle(favorite ? getString(R.string.action_remove_from_favorites) : getString(R.string.action_add_to_favorites));
+            .setTitle(favorite ? getString(R.string.action_remove_from_favorites) : getString(R.string.action_add_to_favorites));
     }
 
     @Override
@@ -366,7 +370,7 @@ public class FlatPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
     @SuppressWarnings("ConstantConditions")
     private static class PortraitImpl extends BaseImpl {
         MediaEntryViewHolder currentSongViewHolder;
-        Song currentSong = Song.EMPTY;
+        Song currentSong;
 
         public PortraitImpl(FlatPlayerFragment fragment, FragmentFlatPlayerBinding binding) {
             super(fragment, binding);
@@ -382,13 +386,13 @@ public class FlatPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
             currentSongViewHolder.image.setColorFilter(ATHUtil.resolveColor(fragment.getActivity(), R.attr.iconColor, ThemeStore.textColorSecondary(fragment.getActivity())), PorterDuff.Mode.SRC_IN);
             currentSongViewHolder.image.setImageResource(R.drawable.ic_volume_up_white_24dp);
             currentSongViewHolder.itemView.setOnClickListener(v -> {
-                // toggle the panel
                 if (binding.playerSlidingLayout.getPanelState() == SlidingUpPanelLayout.PanelState.COLLAPSED) {
                     binding.playerSlidingLayout.setPanelState(SlidingUpPanelLayout.PanelState.EXPANDED);
                 } else if (binding.playerSlidingLayout.getPanelState() == SlidingUpPanelLayout.PanelState.EXPANDED) {
                     binding.playerSlidingLayout.setPanelState(SlidingUpPanelLayout.PanelState.COLLAPSED);
                 }
             });
+
             currentSongViewHolder.menu.setOnClickListener(new SongMenuHelper.OnClickSongMenu((AppCompatActivity) fragment.getActivity()) {
                 @Override
                 public Song getSong() {
@@ -417,10 +421,11 @@ public class FlatPlayerFragment extends AbsPlayerFragment implements PlayerAlbum
 
         @Override
         public void setUpPanelAndAlbumCoverHeight() {
-            WidthFitSquareLayout albumCoverContainer = fragment.getView().findViewById(R.id.album_cover_container);
+            final WidthFitSquareLayout albumCoverContainer = fragment.getView().findViewById(R.id.album_cover_container);
 
             final int availablePanelHeight = binding.playerSlidingLayout.getHeight() - fragment.getView().findViewById(R.id.player_content).getHeight();
             final int minPanelHeight = (int) ViewUtil.convertDpToPixel(8 + 72 + 24, fragment.getResources()) + fragment.getResources().getDimensionPixelSize(R.dimen.progress_container_height) + fragment.getResources().getDimensionPixelSize(R.dimen.media_controller_container_height);
+
             if (availablePanelHeight < minPanelHeight) {
                 albumCoverContainer.getLayoutParams().height = albumCoverContainer.getHeight() - (minPanelHeight - availablePanelHeight);
                 albumCoverContainer.forceSquare(false);

app/src/main/java/com/dkanada/gramophone/helper/MusicPlayerRemote.java

@@ -186,7 +186,7 @@ public class MusicPlayerRemote {
             return musicService.getCurrentSong();
         }
 
-        return Song.EMPTY;
+        return null;
     }
 
     public static int getPosition() {

app/src/main/java/com/dkanada/gramophone/model/Song.java

@@ -16,8 +16,6 @@ import java.util.UUID;
 
 @Entity(tableName = "songs")
 public class Song implements Parcelable {
-    public static final Song EMPTY = new Song();
-
     @NonNull
     @PrimaryKey
     public String id;

app/src/main/java/com/dkanada/gramophone/service/MusicService.java

@@ -177,13 +177,13 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
 
             switch (command) {
                 case AppWidgetClassic.NAME:
-                    appWidgetClassic.performUpdate(MusicService.this, ids);
+                    appWidgetClassic.notifyChange(MusicService.this, META_CHANGED, ids);
                     break;
                 case AppWidgetAlbum.NAME:
-                    appWidgetAlbum.performUpdate(MusicService.this, ids);
+                    appWidgetAlbum.notifyChange(MusicService.this, META_CHANGED, ids);
                     break;
                 case AppWidgetCard.NAME:
-                    appWidgetCard.performUpdate(MusicService.this, ids);
+                    appWidgetCard.notifyChange(MusicService.this, META_CHANGED, ids);
                     break;
             }
         }
@@ -515,8 +515,7 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
 
     private void openCurrent() {
         synchronized (this) {
-            // current song title will be null when queue is cleared
+            if (getCurrentSong() == null) return;
-            if (getCurrentSong().title == null) return;
 
             playback.setDataSource(getCurrentSong());
         }
@@ -529,6 +528,8 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
 
     private void prepareNextImpl() {
         synchronized (this) {
+            if (getCurrentSong() == null) return;
+
             nextPosition = getNextPosition(false);
             playback.queueDataSource(getSongAt(nextPosition));
         }
@@ -549,37 +550,37 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
     }
 
     public void updateNotification() {
-        if (playingNotification != null && getCurrentSong().title != null) {
+        if (playingNotification != null && getCurrentSong() != null) {
             playingNotification.update();
         }
     }
 
     private void updateMediaSessionState() {
         mediaSession.setPlaybackState(
-                new PlaybackStateCompat.Builder()
+            new PlaybackStateCompat.Builder()
-                        .setActions(MEDIA_SESSION_ACTIONS)
+                .setActions(MEDIA_SESSION_ACTIONS)
-                        .setState(isPlaying() ? PlaybackStateCompat.STATE_PLAYING : PlaybackStateCompat.STATE_PAUSED, getSongProgressMillis(), 1)
+                .setState(isPlaying() ? PlaybackStateCompat.STATE_PLAYING : PlaybackStateCompat.STATE_PAUSED, getSongProgressMillis(), 1)
-                        .build());
+                .build());
     }
 
     @SuppressLint("CheckResult")
     private void updateMediaSessionMetadata() {
         final Song song = getCurrentSong();
 
-        if (song.title == null) {
+        if (song == null) {
             mediaSession.setMetadata(null);
             return;
         }
 
         final MediaMetadataCompat.Builder metaData = new MediaMetadataCompat.Builder()
-                .putString(MediaMetadataCompat.METADATA_KEY_ARTIST, song.artistName)
+            .putString(MediaMetadataCompat.METADATA_KEY_ARTIST, song.artistName)
-                .putString(MediaMetadataCompat.METADATA_KEY_ALBUM_ARTIST, song.artistName)
+            .putString(MediaMetadataCompat.METADATA_KEY_ALBUM_ARTIST, song.artistName)
-                .putString(MediaMetadataCompat.METADATA_KEY_ALBUM, song.albumName)
+            .putString(MediaMetadataCompat.METADATA_KEY_ALBUM, song.albumName)
-                .putString(MediaMetadataCompat.METADATA_KEY_TITLE, song.title)
+            .putString(MediaMetadataCompat.METADATA_KEY_TITLE, song.title)
-                .putLong(MediaMetadataCompat.METADATA_KEY_DURATION, song.duration)
+            .putLong(MediaMetadataCompat.METADATA_KEY_DURATION, song.duration)
-                .putLong(MediaMetadataCompat.METADATA_KEY_TRACK_NUMBER, getPosition() + 1)
+            .putLong(MediaMetadataCompat.METADATA_KEY_TRACK_NUMBER, getPosition() + 1)
-                .putLong(MediaMetadataCompat.METADATA_KEY_YEAR, song.year)
+            .putLong(MediaMetadataCompat.METADATA_KEY_YEAR, song.year)
-                .putBitmap(MediaMetadataCompat.METADATA_KEY_ALBUM_ART, null);
+            .putBitmap(MediaMetadataCompat.METADATA_KEY_ALBUM_ART, null);
 
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
             metaData.putLong(MediaMetadataCompat.METADATA_KEY_NUM_TRACKS, getPlayingQueue().size());
@@ -588,8 +589,8 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
         if (PreferenceUtil.getInstance(this).getShowAlbumCover()) {
             final Point screenSize = Util.getScreenSize(MusicService.this);
             final RequestBuilder<Bitmap> request = CustomGlideRequest.Builder
-                    .from(MusicService.this, song.primary, song.blurHash)
+                .from(MusicService.this, song.primary, song.blurHash)
-                    .bitmap().build();
+                .bitmap().build();
 
             if (PreferenceUtil.getInstance(this).getBlurAlbumCover()) {
                 request.transform(new BlurTransformation.Builder(MusicService.this).build());
@@ -638,9 +639,9 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
     public Song getSongAt(int position) {
         if (position >= 0 && position < getPlayingQueue().size()) {
             return getPlayingQueue().get(position);
-        } else {
-            return Song.EMPTY;
         }
+
+        return null;
     }
 
     public int getNextPosition(boolean force) {
@@ -978,9 +979,9 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
     private void sendChangeInternal(final String what) {
         sendBroadcast(new Intent(what));
 
-        appWidgetAlbum.notifyChange(this, what);
+        appWidgetAlbum.notifyChange(this, what, null);
-        appWidgetClassic.notifyChange(this, what);
+        appWidgetClassic.notifyChange(this, what, null);
-        appWidgetCard.notifyChange(this, what);
+        appWidgetCard.notifyChange(this, what, null);
     }
 
     private void handleChangeInternal(@NonNull final String what) {
@@ -1245,6 +1246,9 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
 
         @Override
         public void handleMessage(@NonNull final Message msg) {
+            Song song = mService.get().getCurrentSong();
+            if (song == null) return;
+
             switch (msg.what) {
                 case TRACK_STARTED:
                     onStart();
@@ -1277,19 +1281,22 @@ public class MusicService extends Service implements SharedPreferences.OnSharedP
 
         public void onProgress() {
             PlaybackProgressInfo progressInfo = new PlaybackProgressInfo();
+            Song current = mService.get().getCurrentSong();
+            String user = App.getApiClient().getCurrentUserId();
+            Date time = new Date(System.currentTimeMillis());
+
+            if (current == null) {
+                return;
+            }
 
             // TODO these cause a wrong thread error
             long progress = mService.get().getSongProgressMillis();
             double duration = mService.get().getSongDurationMillis();
             if (progress / duration > 0.9) {
-                Song current = mService.get().getCurrentSong();
-                String user = App.getApiClient().getCurrentUserId();
-                Date time = new Date(System.currentTimeMillis());
-
                 App.getApiClient().MarkPlayedAsync(current.id, user, time, new Response<>());
             }
 
-            progressInfo.setItemId(mService.get().getCurrentSong().id);
+            progressInfo.setItemId(current.id);
             progressInfo.setPositionTicks(progress * 10000);
             progressInfo.setVolumeLevel(mService.get().playback.getVolume());
             progressInfo.setIsPaused(!mService.get().playback.isPlaying());

app/src/main/java/com/dkanada/gramophone/views/widgets/AppWidgetAlbum.java

@@ -53,6 +53,7 @@ public class AppWidgetAlbum extends BaseAppWidget {
         super.onUpdate(context, appWidgetManager, appWidgetIds);
     }
 
+    @Override
     protected void defaultAppWidget(final Context context, final int[] appWidgetIds) {
         final RemoteViews appWidgetView = new RemoteViews(context.getPackageName(), R.layout.app_widget_album);
 
@@ -66,6 +67,7 @@ public class AppWidgetAlbum extends BaseAppWidget {
         pushUpdate(context, appWidgetIds, appWidgetView);
     }
 
+    @Override
     public void performUpdate(final MusicService service, final int[] appWidgetIds) {
         final RemoteViews appWidgetView = new RemoteViews(service.getPackageName(), R.layout.app_widget_album);
 

app/src/main/java/com/dkanada/gramophone/views/widgets/AppWidgetCard.java

@@ -51,6 +51,7 @@ public class AppWidgetCard extends BaseAppWidget {
         super.onUpdate(context, appWidgetManager, appWidgetIds);
     }
 
+    @Override
     protected void defaultAppWidget(final Context context, final int[] appWidgetIds) {
         final RemoteViews appWidgetView = new RemoteViews(context.getPackageName(), R.layout.app_widget_card);
 
@@ -64,6 +65,7 @@ public class AppWidgetCard extends BaseAppWidget {
         pushUpdate(context, appWidgetIds, appWidgetView);
     }
 
+    @Override
     public void performUpdate(final MusicService service, final int[] appWidgetIds) {
         final RemoteViews appWidgetView = new RemoteViews(service.getPackageName(), R.layout.app_widget_card);
 

app/src/main/java/com/dkanada/gramophone/views/widgets/AppWidgetClassic.java

@@ -51,6 +51,7 @@ public class AppWidgetClassic extends BaseAppWidget {
         super.onUpdate(context, appWidgetManager, appWidgetIds);
     }
 
+    @Override
     protected void defaultAppWidget(final Context context, final int[] appWidgetIds) {
         final RemoteViews appWidgetView = new RemoteViews(context.getPackageName(), R.layout.app_widget_classic);
 
@@ -64,6 +65,7 @@ public class AppWidgetClassic extends BaseAppWidget {
         pushUpdate(context, appWidgetIds, appWidgetView);
     }
 
+    @Override
     public void performUpdate(final MusicService service, final int[] appWidgetIds) {
         final RemoteViews appWidgetView = new RemoteViews(service.getPackageName(), R.layout.app_widget_classic);
 

app/src/main/java/com/dkanada/gramophone/views/widgets/BaseAppWidget.java

@@ -48,16 +48,24 @@ public abstract class BaseAppWidget extends AppWidgetProvider {
         context.sendBroadcast(updateIntent);
     }
 
-    public void notifyChange(final MusicService service, final String what) {
+    public void notifyChange(final MusicService service, final String what, int[] appWidgetIds) {
-        if (hasInstances(service)) {
+        final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(service);
-            if (MusicService.META_CHANGED.equals(what) || MusicService.STATE_CHANGED.equals(what)) {
+        final ComponentName componentName = new ComponentName(service, getClass());
-                performUpdate(service, null);
+
-            }
+        // will only find widgets for the current class to avoid updating other styles
+        if (appWidgetIds == null) {
+            appWidgetIds = appWidgetManager.getAppWidgetIds(componentName);
+        }
+
+        Song song = service.getCurrentSong();
+        if (song != null && (what.equals(MusicService.STATE_CHANGED) || what.equals(MusicService.META_CHANGED))) {
+            performUpdate(service, appWidgetIds);
         }
     }
 
     protected void pushUpdate(final Context context, final int[] appWidgetIds, final RemoteViews views) {
         final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
+
         if (appWidgetIds != null) {
             appWidgetManager.updateAppWidget(appWidgetIds, views);
         } else {
@@ -65,13 +73,6 @@ public abstract class BaseAppWidget extends AppWidgetProvider {
         }
     }
 
-    protected boolean hasInstances(final Context context) {
-        final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
-        final int[] mAppWidgetIds = appWidgetManager.getAppWidgetIds(new ComponentName(context, getClass()));
-
-        return mAppWidgetIds.length > 0;
-    }
-
     protected PendingIntent buildPendingIntent(Context context, final String action, final ComponentName serviceName) {
         Intent intent = new Intent(action);
 
@@ -83,7 +84,7 @@ public abstract class BaseAppWidget extends AppWidgetProvider {
         }
     }
 
-    protected static Bitmap createRoundedBitmap(Bitmap bitmap, int width, int height, float tl, float tr, float bl, float br) {
+    protected Bitmap createRoundedBitmap(Bitmap bitmap, int width, int height, float tl, float tr, float bl, float br) {
         Bitmap rounded = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
         Canvas canvas = new Canvas(rounded);
         Paint paint = new Paint();
@@ -96,7 +97,7 @@ public abstract class BaseAppWidget extends AppWidgetProvider {
         return rounded;
     }
 
-    protected static Bitmap createRoundedBitmap(Drawable drawable, int width, int height, float tl, float tr, float bl, float br) {
+    protected Bitmap createRoundedBitmap(Drawable drawable, int width, int height, float tl, float tr, float bl, float br) {
         Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
         Canvas canvas = new Canvas(bitmap);
 
@@ -106,7 +107,7 @@ public abstract class BaseAppWidget extends AppWidgetProvider {
         return createRoundedBitmap(bitmap, width, height, tl, tr, bl, br);
     }
 
-    protected static Path composeRoundedRectPath(RectF rect, float tl, float tr, float bl, float br) {
+    protected Path composeRoundedRectPath(RectF rect, float tl, float tr, float bl, float br) {
         Path path = new Path();
         tl = tl < 0 ? 0 : tl;
         tr = tr < 0 ? 0 : tr;
@@ -129,7 +130,7 @@ public abstract class BaseAppWidget extends AppWidgetProvider {
 
     abstract protected void defaultAppWidget(final Context context, final int[] appWidgetIds);
 
-    abstract public void performUpdate(final MusicService service, final int[] appWidgetIds);
+    abstract protected void performUpdate(final MusicService service, final int[] appWidgetIds);
 
     protected Drawable getAlbumArtDrawable(final Resources resources, final Bitmap bitmap) {
         if (bitmap == null) {