Show correct total number for lazy loaded items

app/src/main/java/de/danoeh/antennapod/adapter/EpisodeItemListAdapter.java

@@ -195,8 +195,8 @@ public class EpisodeItemListAdapter extends SelectableAdapter<EpisodeItemViewHol
             setSelected(0, longPressedPosition, true);
             return true;
         } else if (item.getItemId() == R.id.select_all_below) {
-            setSelected(longPressedPosition + 1, getItemCount(), true);
             shouldSelectLazyLoadedItems = true;
+            setSelected(longPressedPosition + 1, getItemCount(), true);
             return true;
         }
         return false;

app/src/main/java/de/danoeh/antennapod/adapter/SelectableAdapter.java

@@ -15,12 +15,14 @@ import java.util.HashSet;
 /**
  * Used by Recyclerviews that need to provide ability to select items.
  */
-abstract class SelectableAdapter<T extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<T> {
+public abstract class SelectableAdapter<T extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<T> {
+    public static final int COUNT_AUTOMATICALLY = -1;
     private ActionMode actionMode;
     private final HashSet<Long> selectedIds = new HashSet<>();
     private final Activity activity;
     private OnSelectModeListener onSelectModeListener;
     boolean shouldSelectLazyLoadedItems = false;
+    private int totalNumberOfItems = COUNT_AUTOMATICALLY;
 
     public SelectableAdapter(Activity activity) {
         this.activity = activity;
@@ -155,9 +157,17 @@ abstract class SelectableAdapter<T extends RecyclerView.ViewHolder> extends Recy
         if (actionMode == null) {
             return;
         }
+        int totalCount = getItemCount();
+        int selectedCount = selectedIds.size();
+        if (totalNumberOfItems != COUNT_AUTOMATICALLY) {
+            totalCount = totalNumberOfItems;
+            if (shouldSelectLazyLoadedItems) {
+                selectedCount += (totalNumberOfItems - getItemCount());
+            }
+        }
         actionMode.setTitle(activity.getResources()
                 .getQuantityString(R.plurals.num_selected_label, selectedIds.size(),
-                selectedIds.size(), getItemCount()));
+                selectedCount, totalCount));
     }
 
     public void setOnSelectModeListener(OnSelectModeListener onSelectModeListener) {
@@ -174,6 +184,14 @@ abstract class SelectableAdapter<T extends RecyclerView.ViewHolder> extends Recy
         return shouldSelectLazyLoadedItems;
     }
 
+    /**
+     * Sets the total number of items that could be lazy-loaded.
+     * Can also be set to {@link #COUNT_AUTOMATICALLY} to simply use {@link #getItemCount}
+     */
+    public void setTotalNumberOfItems(int totalNumberOfItems) {
+        this.totalNumberOfItems = totalNumberOfItems;
+    }
+
     public interface OnSelectModeListener {
         void onStartSelectMode();
 

app/src/main/java/de/danoeh/antennapod/fragment/AllEpisodesFragment.java

@@ -105,4 +105,9 @@ public class AllEpisodesFragment extends EpisodesListFragment {
     protected List<FeedItem> loadMoreData() {
         return DBReader.getRecentlyPublishedEpisodes((page - 1) * EPISODES_PER_PAGE, EPISODES_PER_PAGE, feedItemFilter);
     }
+
+    @Override
+    protected int loadTotalItemCount() {
+        return DBReader.getTotalEpisodeCount(feedItemFilter);
+    }
 }

app/src/main/java/de/danoeh/antennapod/fragment/EpisodesListFragment.java

@@ -5,6 +5,7 @@ import android.os.Bundle;
 import android.view.ContextMenu;
 import android.view.KeyEvent;
 import androidx.annotation.NonNull;
+import androidx.core.util.Pair;
 import androidx.fragment.app.Fragment;
 import androidx.recyclerview.widget.RecyclerView;
 import androidx.recyclerview.widget.SimpleItemAnimator;
@@ -25,6 +26,7 @@ import android.widget.Toast;
 import com.google.android.material.snackbar.Snackbar;
 import com.leinardi.android.speeddial.SpeedDialView;
 import de.danoeh.antennapod.adapter.EpisodeItemListAdapter;
+import de.danoeh.antennapod.adapter.SelectableAdapter;
 import de.danoeh.antennapod.event.FeedListUpdateEvent;
 import de.danoeh.antennapod.event.playback.PlaybackPositionEvent;
 import de.danoeh.antennapod.event.PlayerStatusEvent;
@@ -447,14 +449,15 @@ public abstract class EpisodesListFragment extends Fragment implements EpisodeIt
         if (disposable != null) {
             disposable.dispose();
         }
-        disposable = Observable.fromCallable(this::loadData)
+        disposable = Observable.fromCallable(() -> new Pair<>(loadData(), loadTotalItemCount()))
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(data -> {
                     progLoading.setVisibility(View.GONE);
                     loadingMoreView.setVisibility(View.GONE);
                     hasMoreItems = true;
-                    episodes = data;
+                    episodes = data.first;
+                    listAdapter.setTotalNumberOfItems(data.second);
                     onFragmentLoaded(episodes);
                     if (getParentFragment() instanceof PagedToolbarFragment) {
                         ((PagedToolbarFragment) getParentFragment()).invalidateOptionsMenuIfActive(this);
@@ -475,4 +478,11 @@ public abstract class EpisodesListFragment extends Fragment implements EpisodeIt
      */
     @NonNull
     protected abstract List<FeedItem> loadMoreData();
+
+    /**
+     * Returns the total number of items that would be returned if {@link #loadMoreData} was called often enough.
+     */
+    protected int loadTotalItemCount() {
+        return SelectableAdapter.COUNT_AUTOMATICALLY;
+    }
 }

app/src/main/java/de/danoeh/antennapod/fragment/FavoriteEpisodesFragment.java

@@ -12,6 +12,7 @@ import android.view.View;
 import android.view.ViewGroup;
 
 import de.danoeh.antennapod.activity.MainActivity;
+import de.danoeh.antennapod.model.feed.FeedItemFilter;
 import de.danoeh.antennapod.view.viewholder.EpisodeItemViewHolder;
 import org.greenrobot.eventbus.Subscribe;
 
@@ -101,4 +102,9 @@ public class FavoriteEpisodesFragment extends EpisodesListFragment {
     protected List<FeedItem> loadMoreData() {
         return DBReader.getFavoriteItemsList((page - 1) * EPISODES_PER_PAGE, EPISODES_PER_PAGE);
     }
+
+    @Override
+    protected int loadTotalItemCount() {
+        return DBReader.getTotalEpisodeCount(new FeedItemFilter(FeedItemFilter.IS_FAVORITE));
+    }
 }

app/src/main/java/de/danoeh/antennapod/fragment/InboxFragment.java

@@ -119,4 +119,9 @@ public class InboxFragment extends EpisodesListFragment implements Toolbar.OnMen
     protected List<FeedItem> loadMoreData() {
         return DBReader.getNewItemsList((page - 1) * EPISODES_PER_PAGE, EPISODES_PER_PAGE);
     }
+
+    @Override
+    protected int loadTotalItemCount() {
+        return DBReader.getTotalEpisodeCount(new FeedItemFilter(FeedItemFilter.NEW));
+    }
 }

core/src/main/java/de/danoeh/antennapod/core/storage/DBReader.java

@@ -402,6 +402,19 @@ public final class DBReader {
         }
     }
 
+    public static int getTotalEpisodeCount(FeedItemFilter filter) {
+        PodDBAdapter adapter = PodDBAdapter.getInstance();
+        adapter.open();
+        try (Cursor cursor = adapter.getTotalEpisodeCountCursor(filter)) {
+            if (cursor.moveToFirst()) {
+                return cursor.getInt(0);
+            }
+            return -1;
+        } finally {
+            adapter.close();
+        }
+    }
+
     /**
      * Loads the playback history from the database. A FeedItem is in the playback history if playback of the correpsonding episode
      * has been completed at least once.

storage/database/src/main/java/de/danoeh/antennapod/storage/database/PodDBAdapter.java

@@ -1052,6 +1052,14 @@ public class PodDBAdapter {
         return db.rawQuery(query, null);
     }
 
+    public final Cursor getTotalEpisodeCountCursor(FeedItemFilter filter) {
+        String filterQuery = FeedItemFilterQuery.generateFrom(filter);
+        String whereClause = "".equals(filterQuery) ? "" : " WHERE " + filterQuery;
+        final String query = "SELECT count(" + TABLE_NAME_FEED_ITEMS + "." + KEY_ID + ") FROM " + TABLE_NAME_FEED_ITEMS
+                + JOIN_FEED_ITEM_AND_MEDIA + whereClause;
+        return db.rawQuery(query, null);
+    }
+
     public Cursor getDownloadedItemsCursor() {
         final String query = SELECT_FEED_ITEMS_AND_MEDIA
                 + "WHERE " + TABLE_NAME_FEED_MEDIA + "." + KEY_DOWNLOADED + " > 0";

storage/database/src/main/java/de/danoeh/antennapod/storage/database/mapper/FeedItemFilterQuery.java

@@ -34,6 +34,8 @@ public class FeedItemFilterQuery {
             statements.add(keyRead + " = 1 ");
         } else if (filter.showUnplayed) {
             statements.add(" NOT " + keyRead + " = 1 "); // Match "New" items (read = -1) as well
+        } else if (filter.showNew) {
+            statements.add(keyRead + " = -1 ");
         }
         if (filter.showPaused) {
             statements.add(" (" + keyPosition + " NOT NULL AND " + keyPosition + " > 0 " + ") ");