add option to expand special category, disable ACRA for debug builds, move most of feed-related processing to models

6 files changed, 322 insertions, 231 deletions

diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java
index 17ae7ccf..56546a33 100755
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/Application.java
@@ -65,7 +65,7 @@ public class Application extends android.app.Application {
 	public void setApiLevel(int apiLevel) {
 		m_apiLevel = apiLevel;
 	}
-	
+
 	public void save(Bundle out) {
 		
 		out.setClassLoader(getClass().getClassLoader());
@@ -100,20 +100,21 @@ public class Application extends android.app.Application {
 	protected void attachBaseContext(Context base) {
 		super.attachBaseContext(base);
 
-		ACRA.init(this, new CoreConfigurationBuilder()
-				.withBuildConfigClass(BuildConfig.class)
-				.withReportFormat(StringFormat.JSON)
-				.withPluginConfigurations(
-						new DialogConfigurationBuilder()
-								.withText(getString(R.string.crash_dialog_text_email))
-								.withResTheme(R.style.Theme_AppCompat_Dialog)
-								.build(),
-						new MailSenderConfigurationBuilder()
-								.withMailTo("cthulhoo+ttrss-acra@gmail.com")
-								.withReportAsFile(true)
-								.withReportFileName("crash.txt")
-								.build()
-				)
-				.build());
+		if (!BuildConfig.DEBUG)
+			ACRA.init(this, new CoreConfigurationBuilder()
+					.withBuildConfigClass(BuildConfig.class)
+					.withReportFormat(StringFormat.JSON)
+					.withPluginConfigurations(
+							new DialogConfigurationBuilder()
+									.withText(getString(R.string.crash_dialog_text_email))
+									.withResTheme(R.style.Theme_AppCompat_Dialog)
+									.build(),
+							new MailSenderConfigurationBuilder()
+									.withMailTo("cthulhoo+ttrss-acra@gmail.com")
+									.withReportAsFile(true)
+									.withReportFileName("crash.txt")
+									.build()
+					)
+					.build());
 	}
 }
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsFragment.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsFragment.java
index d86969cc..8dcda413 100755
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsFragment.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsFragment.java
@@ -68,77 +68,6 @@ public class FeedsFragment extends Fragment implements OnSharedPreferenceChangeL
 		m_enableParentBtn = enableParentBtn;
 	}
 
-	@SuppressLint("DefaultLocale")
-	static class FeedUnreadComparator implements Comparator<Feed> {
-
-		@Override
-		public int compare(Feed a, Feed b) {
-			if (a.unread != b.unread)
-					return b.unread - a.unread;
-				else
-					return a.title.toUpperCase().compareTo(b.title.toUpperCase());
-			}
-
-	}
-
-	@SuppressLint("DefaultLocale")
-	static class FeedTitleComparator implements Comparator<Feed> {
-
-		@Override
-		public int compare(Feed a, Feed b) {
-			if (a.is_cat && b.is_cat)
-				return a.title.toUpperCase().compareTo(b.title.toUpperCase());
-			else if (a.is_cat && !b.is_cat)
-				return -1;
-			else if (!a.is_cat && b.is_cat)
-				return 1;
-			else if (a.id >= 0 && b.id >= 0)
-				return a.title.toUpperCase().compareTo(b.title.toUpperCase());
-			else
-				return a.id - b.id;			
-		}
-		
-	}
-
-	@SuppressLint("DefaultLocale")
-	static class SpecialOrderComparator implements Comparator<Feed> {
-		static List<Integer> order = Arrays.asList(Feed.ALL_ARTICLES, Feed.FRESH, Feed.MARKED,
-				Feed.PUBLISHED, Feed.ARCHIVED, Feed.RECENTLY_READ);
-
-		@Override
-		public int compare(Feed a, Feed b) {
-			return Integer.valueOf(order.indexOf(a.id)).compareTo(order.indexOf(b.id));
-		}
-	}
-
-	@SuppressLint("DefaultLocale")
-	static class FeedOrderComparator implements Comparator<Feed> {
-
-		@Override
-		public int compare(Feed a, Feed b) {
-			if (a.id >= 0 && b.id >= 0)
-				if (a.is_cat && b.is_cat)
-					if (a.order_id != 0 && b.order_id != 0)
-						return a.order_id - b.order_id;
-					else
-						return a.title.toUpperCase().compareTo(b.title.toUpperCase());
-				else if (a.is_cat)
-					return -1;
-				else if (b.is_cat)
-					return 1;
-				else if (a.order_id != 0 && b.order_id != 0)
-					return a.order_id - b.order_id;
-				else
-					return a.title.toUpperCase().compareTo(b.title.toUpperCase());
-			else
-				if (a.id < CommonActivity.LABEL_BASE_INDEX && b.id < CommonActivity.LABEL_BASE_INDEX)
-					return a.title.toUpperCase().compareTo(b.title.toUpperCase());
-				else
-					return a.id - b.id;
-		}
-		
-	}
-	
 	@Override
 	public boolean onContextItemSelected(MenuItem item) {
 		AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) item
@@ -284,7 +213,7 @@ public class FeedsFragment extends Fragment implements OnSharedPreferenceChangeL
 			});
 		}
 
-		FeedsModel model = new ViewModelProvider(this).get(FeedsModel.class);
+		FeedsModel model = getModel();
 
 		model.getUpdatesData().observe(m_activity, lastUpdate -> {
 			Log.d(TAG, "observed update=" + lastUpdate);
@@ -334,16 +263,13 @@ public class FeedsFragment extends Fragment implements OnSharedPreferenceChangeL
 		return view;    	
 	}
 
+	protected FeedsModel getModel() {
+		return new ViewModelProvider(this).get(FeedsModel.class);
+	}
+
 	protected void onFeedsLoaded(List<Feed> loadedFeeds) {
 		List<Feed> feedsWork = new ArrayList<>();
 
-		if (m_activity.getUnreadOnly() && m_rootFeed.id != Feed.CAT_SPECIAL)
-			loadedFeeds = loadedFeeds.stream()
-					.filter(f -> f.unread > 0)
-					.collect(Collectors.toList());
-
-		sortFeeds(loadedFeeds, m_rootFeed);
-
 		if (m_enableParentBtn) {
 			feedsWork.add(0, new Feed(Feed.TYPE_GOBACK));
 
@@ -403,8 +329,7 @@ public class FeedsFragment extends Fragment implements OnSharedPreferenceChangeL
 		if (!isAdded())
 			return;
 
-		FeedsModel model = new ViewModelProvider(this).get(FeedsModel.class);
-		model.startLoading(m_rootFeed, false);
+		getModel().startLoading(m_rootFeed);
 	}
 
 	private class FeedViewHolder extends RecyclerView.ViewHolder {
@@ -582,35 +507,11 @@ public class FeedsFragment extends Fragment implements OnSharedPreferenceChangeL
 		return feed.id == Feed.CAT_SPECIAL || feed.id == Feed.CAT_LABELS;
 	}
 
-	protected void sortFeeds(List<Feed> feeds, Feed feed) {
-		Comparator<Feed> cmp;
-
-		if (feed.id == -1) {
-			cmp = new SpecialOrderComparator();
-		} else {
-			if (m_prefs.getBoolean("sort_feeds_by_unread", false)) {
-				cmp = new FeedUnreadComparator();
-			} else {
-				if (m_activity.getApiLevel() >= 3) {
-					cmp = new FeedOrderComparator();
-				} else {
-					cmp = new FeedTitleComparator();
-				}
-			}
-		}
-
-		try {
-			feeds.sort(cmp);
-		} catch (IllegalArgumentException e) {
-			//
-		}
-	}
-
 	protected int getIconForFeed(Feed feed) {
 		if (feed.id == Feed.TYPE_GOBACK) {
 			return R.drawable.baseline_arrow_back_24;
 		} else if (feed.id == Feed.CAT_LABELS && feed.is_cat) {
-			return R.drawable.outline_label_24;
+			return R.drawable.baseline_label_24;
 		} else if (feed.id == Feed.CAT_SPECIAL && feed.is_cat) {
 			return R.drawable.baseline_folder_special_24;
 		} else if (feed.id == Feed.TYPE_TOGGLE_UNREAD) {
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsModel.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsModel.java
index 171fb29a..66fd0443 100644
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsModel.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/FeedsModel.java
@@ -1,14 +1,18 @@
 package org.fox.ttrss;
 
+import android.annotation.SuppressLint;
 import android.app.Application;
+import android.content.SharedPreferences;
 import android.os.Handler;
 import android.os.Looper;
 import android.util.Log;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 import androidx.lifecycle.AndroidViewModel;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
+import androidx.preference.PreferenceManager;
 
 import com.google.gson.Gson;
 import com.google.gson.JsonArray;
@@ -20,6 +24,8 @@ import org.fox.ttrss.types.Feed;
 
 import java.lang.reflect.Type;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
 import java.util.concurrent.ExecutorService;
@@ -28,28 +34,28 @@ import java.util.stream.Collectors;
 
 public class FeedsModel extends AndroidViewModel implements ApiCommon.ApiCaller {
     private final String TAG = this.getClass().getSimpleName();
-    private MutableLiveData<List<Feed>> m_feeds = new MutableLiveData<>(new ArrayList<>());
-    private MutableLiveData<Integer> m_loadingProgress = new MutableLiveData<>(Integer.valueOf(0));
-    private MutableLiveData<Long> m_lastUpdate = new MutableLiveData<>(Long.valueOf(0));
-    private MutableLiveData<Boolean> m_isLoading = new MutableLiveData<>(Boolean.valueOf(false));
+    protected MutableLiveData<List<Feed>> m_feeds = new MutableLiveData<>(new ArrayList<>());
+    protected MutableLiveData<Integer> m_loadingProgress = new MutableLiveData<>(Integer.valueOf(0));
+    protected MutableLiveData<Long> m_lastUpdate = new MutableLiveData<>(Long.valueOf(0));
+    protected MutableLiveData<Boolean> m_isLoading = new MutableLiveData<>(Boolean.valueOf(false));
 
-    private Feed m_feed;
+    protected Feed m_feed;
 
-    private ExecutorService m_executor;
-    private Handler m_mainHandler = new Handler(Looper.getMainLooper());
+    protected ExecutorService m_executor = Executors.newSingleThreadExecutor();
+    protected Handler m_mainHandler = new Handler(Looper.getMainLooper());
 
     private final int m_responseCode = 0;
     protected String m_responseMessage;
     private int m_apiStatusCode = 0;
     private String m_lastErrorMessage;
     private ApiCommon.ApiError m_lastError;
-    private boolean m_rootMode;
+
+    protected SharedPreferences m_prefs;
 
     public FeedsModel(@NonNull Application application) {
         super(application);
 
-        // do we need concurrency or not?
-        m_executor = Executors.newSingleThreadExecutor();
+        m_prefs = PreferenceManager.getDefaultSharedPreferences(application);
 
         Log.d(TAG, this + " created");
     }
@@ -69,11 +75,10 @@ public class FeedsModel extends AndroidViewModel implements ApiCommon.ApiCaller
         m_lastErrorMessage = message;
     }
 
-    public void startLoading(Feed feed, boolean rootMode) {
+    public void startLoading(Feed feed) {
         Log.d(TAG, "startLoading feed id=" + feed.id + " cat=" + feed.is_cat);
 
         m_feed = feed;
-        m_rootMode = rootMode;
 
         loadInBackground();
     }
@@ -83,48 +88,45 @@ public class FeedsModel extends AndroidViewModel implements ApiCommon.ApiCaller
         m_loadingProgress.postValue(progress);
     }
 
-    protected HashMap<String,String> constructParams() {
-        HashMap<String,String> params = new HashMap<>();
+    protected void loadInBackground() {
+        Log.d(TAG, this + " loadInBackground");
+
+        m_isLoading.postValue(true);
 
-        if (m_rootMode) {
-            params.put("op", "getCategories");
+        m_executor.execute(() -> {
+            final HashMap<String,String> params = new HashMap<>();
 
-            // this confusingly named option means "return top level categories only"
-            params.put("enable_nested", "true");
-        } else {
             params.put("op", "getFeeds");
             params.put("cat_id", String.valueOf(m_feed.id));
             params.put("include_nested", "true");
-        }
+            params.put("sid", ((org.fox.ttrss.Application)getApplication()).getSessionId());
 
-        params.put("sid", ((org.fox.ttrss.Application)getApplication()).getSessionId());
-
-        return params;
-    }
-
-    private void loadInBackground() {
-        Log.d(TAG, this + " loadInBackground");
-
-        m_isLoading.postValue(true);
-
-        HashMap<String,String> params = constructParams();
-
-        m_executor.execute(() -> {
-            JsonElement result = ApiCommon.performRequest(getApplication(), params, this);
+            final JsonElement result = ApiCommon.performRequest(getApplication(), params, this);
 
             Log.d(TAG, "got result=" + result);
 
+            boolean unreadOnly = m_prefs.getBoolean("show_unread_only", true);
+
             try {
                 JsonArray content = result.getAsJsonArray();
                 if (content != null) {
 
                     Type listType = new TypeToken<List<Feed>>() {}.getType();
 
-                    List<Feed> feeds = new Gson().fromJson(content, listType);
+                    List<Feed> feedsJson = new Gson().fromJson(content, listType);
 
-                    feeds = feeds.stream().peek(Feed::fixNullFields).collect(Collectors.toList());
+                    // seems to be necessary evil because of deserialization
+                    feedsJson = feedsJson.stream().peek(Feed::fixNullFields).collect(Collectors.toList());
 
-                    m_feeds.postValue(feeds);
+
+		            if (unreadOnly && m_feed.id != Feed.CAT_SPECIAL)
+			            feedsJson = feedsJson.stream()
+                            .filter(f -> f.unread > 0)
+                            .collect(Collectors.toList());
+
+                    sortFeeds(feedsJson, m_feed, null);
+
+                    m_feeds.postValue(feedsJson);
                 }
             } catch (Exception e) {
                 e.printStackTrace();
@@ -160,4 +162,100 @@ public class FeedsModel extends AndroidViewModel implements ApiCommon.ApiCaller
         return m_lastErrorMessage;
     }
 
+    @SuppressLint("DefaultLocale")
+    static class FeedOrderComparator implements Comparator<Feed> {
+
+        @Override
+        public int compare(Feed a, Feed b) {
+            if (a.id >= 0 && b.id >= 0)
+                if (a.is_cat && b.is_cat)
+                    if (a.order_id != 0 && b.order_id != 0)
+                        return a.order_id - b.order_id;
+                    else
+                        return a.title.toUpperCase().compareTo(b.title.toUpperCase());
+                else if (a.is_cat)
+                    return -1;
+                else if (b.is_cat)
+                    return 1;
+                else if (a.order_id != 0 && b.order_id != 0)
+                    return a.order_id - b.order_id;
+                else
+                    return a.title.toUpperCase().compareTo(b.title.toUpperCase());
+            else
+            if (a.id < CommonActivity.LABEL_BASE_INDEX && b.id < CommonActivity.LABEL_BASE_INDEX)
+                return a.title.toUpperCase().compareTo(b.title.toUpperCase());
+            else
+                return a.id - b.id;
+        }
+
+    }
+
+    @SuppressLint("DefaultLocale")
+    static class FeedUnreadComparator implements Comparator<Feed> {
+
+        @Override
+        public int compare(Feed a, Feed b) {
+            if (a.unread != b.unread)
+                return b.unread - a.unread;
+            else
+                return a.title.toUpperCase().compareTo(b.title.toUpperCase());
+        }
+
+    }
+
+    @SuppressLint("DefaultLocale")
+    static class FeedTitleComparator implements Comparator<Feed> {
+
+        @Override
+        public int compare(Feed a, Feed b) {
+            if (a.is_cat && b.is_cat)
+                return a.title.toUpperCase().compareTo(b.title.toUpperCase());
+            else if (a.is_cat && !b.is_cat)
+                return -1;
+            else if (!a.is_cat && b.is_cat)
+                return 1;
+            else if (a.id >= 0 && b.id >= 0)
+                return a.title.toUpperCase().compareTo(b.title.toUpperCase());
+            else
+                return a.id - b.id;
+        }
+
+    }
+
+    @SuppressLint("DefaultLocale")
+    static class SpecialOrderComparator implements Comparator<Feed> {
+        static List<Integer> order = Arrays.asList(Feed.ALL_ARTICLES, Feed.FRESH, Feed.MARKED,
+                Feed.PUBLISHED, Feed.ARCHIVED, Feed.RECENTLY_READ);
+
+        @Override
+        public int compare(Feed a, Feed b) {
+            return Integer.valueOf(order.indexOf(a.id)).compareTo(order.indexOf(b.id));
+        }
+    }
+
+    protected void sortFeeds(@NonNull List<Feed> feeds, @NonNull Feed feed, @Nullable Comparator<Feed> comparator) {
+
+        if (comparator == null) {
+            if (feed.id == -1) {
+                comparator = new SpecialOrderComparator();
+            } else {
+                if (m_prefs.getBoolean("sort_feeds_by_unread", false)) {
+                    comparator = new FeedUnreadComparator();
+                } else {
+                    if (org.fox.ttrss.Application.getInstance().getApiLevel() >= 3) {
+                        comparator = new FeedOrderComparator();
+                    } else {
+                        comparator = new FeedTitleComparator();
+                    }
+                }
+            }
+        }
+
+        try {
+            feeds.sort(comparator);
+        } catch (IllegalArgumentException e) {
+            //
+        }
+   }
+
 }
\ No newline at end of file
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/RootCategoriesFragment.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/RootCategoriesFragment.java
index e94d0405..7e548879 100755
--- a/org.fox.ttrss/src/main/java/org/fox/ttrss/RootCategoriesFragment.java
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/RootCategoriesFragment.java
@@ -24,75 +24,8 @@ import java.util.stream.Collectors;
 public class RootCategoriesFragment extends FeedsFragment {
 	private final String TAG = this.getClass().getSimpleName();
 
-	@SuppressLint("DefaultLocale")
-	static class CatOrderComparator implements Comparator<Feed> {
-
-		@Override
-		public int compare(Feed a, Feed b) {
-			if (a.id >= 0 && b.id >= 0)
-				if (a.order_id != 0 && b.order_id != 0)
-					return a.order_id - b.order_id;
-				else
-					return a.title.toUpperCase().compareTo(b.title.toUpperCase());
-			else
-				return a.id - b.id;
-		}
-
-	}
-
 	@Override
-	protected void sortFeeds(List<Feed> feeds, Feed feed) {
-		try {
-			feeds.sort(new CatOrderComparator());
-		} catch (IllegalArgumentException e) {
-			//
-		}
-	}
-
-	@Override
-	public void refresh() {
-		if (!isAdded())
-			return;
-
-		FeedsModel model = new ViewModelProvider(this).get(FeedsModel.class);
-		model.startLoading(m_rootFeed, true);
-	}
-
-	@Override
-	protected void onFeedsLoaded(List<Feed> loadedFeeds) {
-		List<Feed> feedsWork = new ArrayList<>();
-
-		sortFeeds(loadedFeeds, m_rootFeed);
-
-		// virtual cats implemented in getCategories since api level 1
-		if (m_activity.getApiLevel() == 0) {
-			feedsWork.add(0, new Feed(-2, getString(R.string.cat_labels), true));
-			feedsWork.add(1, new Feed(-1, getString(R.string.cat_special), true));
-			feedsWork.add(new Feed(0, getString(R.string.cat_uncategorized), true));
-		}
-
-		if (m_activity.getUnreadOnly())
-			loadedFeeds = loadedFeeds.stream()
-					.filter(f -> f.id == Feed.CAT_SPECIAL || f.unread > 0)
-					.collect(Collectors.toList());
-
-		loadedFeeds = loadedFeeds.stream()
-				.peek(f -> f.is_cat = true)
-				.collect(Collectors.toList());
-
-		/* if (m_prefs.getBoolean("expand_special_cat", true)) {
-			loadedFeeds = loadedFeeds.stream()
-					.filter(f -> f.id != Feed.CAT_SPECIAL && f.id != Feed.CAT_LABELS)
-					.collect(Collectors.toList());
-		} */
-
-		feedsWork.addAll(loadedFeeds);
-
-		feedsWork.add(new Feed(Feed.TYPE_DIVIDER));
-		feedsWork.add(new Feed(Feed.TYPE_TOGGLE_UNREAD, getString(R.string.unread_only), true));
-
-		m_adapter.submitList(feedsWork);
-
+	protected FeedsModel getModel() {
+		return new ViewModelProvider(this).get(RootCategoriesModel.class);
 	}
 }
-
diff --git a/org.fox.ttrss/src/main/java/org/fox/ttrss/RootCategoriesModel.java b/org.fox.ttrss/src/main/java/org/fox/ttrss/RootCategoriesModel.java
new file mode 100644
index 00000000..d5668aa8
--- /dev/null
+++ b/org.fox.ttrss/src/main/java/org/fox/ttrss/RootCategoriesModel.java
@@ -0,0 +1,159 @@
+package org.fox.ttrss;
+
+import android.annotation.SuppressLint;
+import android.app.Application;
+import android.util.Log;
+
+import androidx.annotation.NonNull;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonArray;
+import com.google.gson.JsonElement;
+import com.google.gson.reflect.TypeToken;
+
+import org.fox.ttrss.types.Feed;
+
+import java.lang.reflect.Type;
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.HashMap;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class RootCategoriesModel extends FeedsModel {
+    private final String TAG = this.getClass().getSimpleName();
+
+    public RootCategoriesModel(@NonNull Application application) {
+        super(application);
+    }
+
+    @Override
+    protected void loadInBackground() {
+        Log.d(TAG, this + " loadInBackground");
+
+        m_isLoading.postValue(true);
+
+        boolean expandSpecial = m_prefs.getBoolean("expand_special_cat", true);
+
+        final List<Feed> feedsCombined = new ArrayList<>();
+
+        m_executor.execute(() -> {
+
+            // get special category with counters for embedding
+            if (expandSpecial) {
+                final HashMap<String, String> params = new HashMap<>();
+
+                params.put("op", "getFeeds");
+                params.put("cat_id", String.valueOf(Feed.CAT_SPECIAL));
+                params.put("include_nested", "true");
+                params.put("sid", ((org.fox.ttrss.Application)getApplication()).getSessionId());
+
+                final JsonElement result = ApiCommon.performRequest(getApplication(), params, this);
+
+                Log.d(TAG, "got result=" + result);
+
+                try {
+                    JsonArray content = result.getAsJsonArray();
+                    if (content != null) {
+
+                        Type listType = new TypeToken<List<Feed>>() { }.getType();
+
+                        List<Feed> feedsJson = new Gson().fromJson(content, listType);
+
+                        // seems to be necessary evil because of deserialization
+                        feedsJson = feedsJson.stream().peek(Feed::fixNullFields).collect(Collectors.toList());
+
+                        sortFeeds(feedsJson, m_feed, new SpecialOrderComparator());
+
+                        feedsCombined.addAll(feedsJson);
+
+                        feedsCombined.add(new Feed(Feed.TYPE_DIVIDER));
+                    }
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+            }
+
+            // get all root categories
+            final HashMap<String,String> params = new HashMap<>();
+
+            params.put("op", "getCategories");
+            params.put("sid", ((org.fox.ttrss.Application)getApplication()).getSessionId());
+
+            // this confusingly named option means "return top level categories only"
+            params.put("enable_nested", "true");
+
+            final JsonElement result = ApiCommon.performRequest(getApplication(), params, this);
+
+            Log.d(TAG, "got result=" + result);
+
+            boolean unreadOnly = m_prefs.getBoolean("show_unread_only", true);
+
+            try {
+                JsonArray content = result.getAsJsonArray();
+                if (content != null) {
+
+                    Type listType = new TypeToken<List<Feed>>() {}.getType();
+
+                    List<Feed> feedsJson = new Gson().fromJson(content, listType);
+
+                    // seems to be necessary evil because of deserialization
+                    feedsJson = feedsJson.stream().peek(Feed::fixNullFields).collect(Collectors.toList());
+
+		            sortFeeds(feedsJson, m_feed, new CatOrderComparator());
+
+                    // virtual cats implemented in getCategories since api level 1
+                    if (org.fox.ttrss.Application.getInstance().getApiLevel() == 0) {
+                        feedsCombined.add(0, new Feed(-2, getApplication().getString(R.string.cat_labels), true));
+
+                        if (!expandSpecial)
+                            feedsCombined.add(1, new Feed(-1, getApplication().getString(R.string.cat_special), true));
+
+                        feedsCombined.add(new Feed(0, getApplication().getString(R.string.cat_uncategorized), true));
+                    }
+
+                    if (unreadOnly)
+                        feedsJson = feedsJson.stream()
+                                .filter(f -> f.id == Feed.CAT_SPECIAL || f.unread > 0)
+                                .collect(Collectors.toList());
+
+                    // force returned objects to become categories
+                    feedsJson = feedsJson.stream()
+                            .peek(f -> f.is_cat = true)
+                            .collect(Collectors.toList());
+
+		            if (expandSpecial) {
+                        feedsJson = feedsJson.stream()
+                                .filter(f -> f.id != Feed.CAT_SPECIAL)
+                                .collect(Collectors.toList());
+		            }
+
+                    feedsCombined.addAll(feedsJson);
+
+                    m_feeds.postValue(feedsCombined);
+                }
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+
+            m_isLoading.postValue(false);
+        });
+    }
+
+    @SuppressLint("DefaultLocale")
+    static class CatOrderComparator implements Comparator<Feed> {
+
+        @Override
+        public int compare(Feed a, Feed b) {
+            if (a.id >= 0 && b.id >= 0)
+                if (a.order_id != 0 && b.order_id != 0)
+                    return a.order_id - b.order_id;
+                else
+                    return a.title.toUpperCase().compareTo(b.title.toUpperCase());
+            else
+                return a.id - b.id;
+        }
+
+    }
+
+}
diff --git a/org.fox.ttrss/src/main/res/xml/preferences.xml b/org.fox.ttrss/src/main/res/xml/preferences.xml
index a5a49e04..df3dbc42 100755
--- a/org.fox.ttrss/src/main/res/xml/preferences.xml
+++ b/org.fox.ttrss/src/main/res/xml/preferences.xml
@@ -62,12 +62,11 @@
             android:summary="@string/browse_cats_like_feeds_summary"
             android:title="@string/browse_cats_like_feeds" />
 
-        <!--
         <SwitchPreferenceCompat
             android:defaultValue="true"
-            android:dependency="@string/enable_cats"
+            android:dependency="enable_cats"
             android:key="expand_special_cat"
-            android:title="@string/expand_special_cat" /> -->
+            android:title="@string/expand_special_cat" />
 
         <ListPreference
             android:defaultValue="0"