Fixed no posts, no comments, no users and no subreddits message cannot be retained after orientation change in PostFragment, CommentsListingFragment, UserListingFragment and SubredditListingFragment respectively. Minor bugs fixed.

app/src/main/java/ml/docilealligator/infinityforreddit/CheckIsSubscribedToSubredditAsyncTask.java

@@ -2,12 +2,11 @@ package ml.docilealligator.infinityforreddit;
 
 import android.os.AsyncTask;
 
-import SubscribedSubredditDatabase.SubscribedSubredditDao;
 import SubscribedSubredditDatabase.SubscribedSubredditData;
 
 class CheckIsSubscribedToSubredditAsyncTask extends AsyncTask<Void, Void, Void> {
 
-    private SubscribedSubredditDao subscribedSubredditDao;
+    private RedditDataRoomDatabase redditDataRoomDatabase;
     private String subredditName;
     private String accountName;
     private SubscribedSubredditData subscribedSubredditData;
@@ -18,10 +17,10 @@ class CheckIsSubscribedToSubredditAsyncTask extends AsyncTask<Void, Void, Void>
         void isNotSubscribed();
     }
 
-    CheckIsSubscribedToSubredditAsyncTask(SubscribedSubredditDao subscribedSubredditDao,
+    CheckIsSubscribedToSubredditAsyncTask(RedditDataRoomDatabase redditDataRoomDatabase,
                                           String subredditName, String accountName,
                                           CheckIsSubscribedToSubredditListener checkIsSubscribedToSubredditListener) {
-        this.subscribedSubredditDao = subscribedSubredditDao;
+        this.redditDataRoomDatabase = redditDataRoomDatabase;
         this.subredditName =subredditName;
         this.accountName = accountName;
         this.checkIsSubscribedToSubredditListener = checkIsSubscribedToSubredditListener;
@@ -29,7 +28,7 @@ class CheckIsSubscribedToSubredditAsyncTask extends AsyncTask<Void, Void, Void>
 
     @Override
     protected Void doInBackground(Void... voids) {
-        subscribedSubredditData = subscribedSubredditDao.getSubscribedSubreddit(subredditName, accountName);
+        subscribedSubredditData = redditDataRoomDatabase.subscribedSubredditDao().getSubscribedSubreddit(subredditName, accountName);
         return null;
     }
 

app/src/main/java/ml/docilealligator/infinityforreddit/CommentDataSource.java

@@ -20,41 +20,41 @@ import retrofit2.Response;
 import retrofit2.Retrofit;
 
 public class CommentDataSource extends PageKeyedDataSource<String, CommentData> {
-    interface OnCommentFetchedCallback {
-        void hasComment();
-        void noComment();
-    }
 
     private Retrofit retrofit;
     private Locale locale;
     private String username;
-    private OnCommentFetchedCallback onCommentFetchedCallback;
 
     private MutableLiveData<NetworkState> paginationNetworkStateLiveData;
     private MutableLiveData<NetworkState> initialLoadStateLiveData;
+    private MutableLiveData<Boolean> hasPostLiveData;
 
     private LoadInitialParams<String> initialParams;
     private LoadInitialCallback<String, CommentData> initialCallback;
     private LoadParams<String> params;
     private LoadCallback<String, CommentData> callback;
 
-    CommentDataSource(Retrofit retrofit, Locale locale, String username, OnCommentFetchedCallback onCommentFetchedCallback) {
+    CommentDataSource(Retrofit retrofit, Locale locale, String username) {
         this.retrofit = retrofit;
         this.locale = locale;
         this.username = username;
-        paginationNetworkStateLiveData = new MutableLiveData();
+        paginationNetworkStateLiveData = new MutableLiveData<>();
-        initialLoadStateLiveData = new MutableLiveData();
+        initialLoadStateLiveData = new MutableLiveData<>();
-        this.onCommentFetchedCallback = onCommentFetchedCallback;
+        hasPostLiveData = new MutableLiveData<>();
     }
 
-    MutableLiveData getPaginationNetworkStateLiveData() {
+    MutableLiveData<NetworkState> getPaginationNetworkStateLiveData() {
         return paginationNetworkStateLiveData;
     }
 
-    MutableLiveData getInitialLoadStateLiveData() {
+    MutableLiveData<NetworkState> getInitialLoadStateLiveData() {
         return initialLoadStateLiveData;
     }
 
+    MutableLiveData<Boolean> hasPostLiveData() {
+        return hasPostLiveData;
+    }
+
     void retry() {
         loadInitial(initialParams, initialCallback);
     }
@@ -80,9 +80,9 @@ public class CommentDataSource extends PageKeyedDataSource<String, CommentData>
                         @Override
                         public void parseSuccessful(ArrayList<CommentData> comments, String after) {
                             if(comments.size() == 0) {
-                                onCommentFetchedCallback.noComment();
+                                hasPostLiveData.postValue(false);
                             } else {
-                                onCommentFetchedCallback.hasComment();
+                                hasPostLiveData.postValue(true);
                             }
 
                             callback.onResult(comments, null, after);

app/src/main/java/ml/docilealligator/infinityforreddit/CommentDataSourceFactory.java

@@ -12,23 +12,21 @@ class CommentDataSourceFactory extends DataSource.Factory {
     private Retrofit retrofit;
     private Locale locale;
     private String username;
-    private CommentDataSource.OnCommentFetchedCallback onCommentFetchedCallback;
 
     private CommentDataSource commentDataSource;
     private MutableLiveData<CommentDataSource> commentDataSourceLiveData;
 
-    CommentDataSourceFactory(Retrofit retrofit, Locale locale, String username, CommentDataSource.OnCommentFetchedCallback onCommentFetchedCallback) {
+    CommentDataSourceFactory(Retrofit retrofit, Locale locale, String username) {
         this.retrofit = retrofit;
         this.locale = locale;
         this.username = username;
         commentDataSourceLiveData = new MutableLiveData<>();
-        this.onCommentFetchedCallback = onCommentFetchedCallback;
     }
 
     @NonNull
     @Override
     public DataSource create() {
-        commentDataSource = new CommentDataSource(retrofit, locale, username, onCommentFetchedCallback);
+        commentDataSource = new CommentDataSource(retrofit, locale, username);
         commentDataSourceLiveData.postValue(commentDataSource);
         return commentDataSource;
     }

app/src/main/java/ml/docilealligator/infinityforreddit/CommentViewModel.java

@@ -1,7 +1,6 @@
 package ml.docilealligator.infinityforreddit;
 
 import androidx.annotation.NonNull;
-import androidx.arch.core.util.Function;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.Transformations;
 import androidx.lifecycle.ViewModel;
@@ -17,16 +16,18 @@ public class CommentViewModel extends ViewModel {
     private CommentDataSourceFactory commentDataSourceFactory;
     private LiveData<NetworkState> paginationNetworkState;
     private LiveData<NetworkState> initialLoadingState;
+    private LiveData<Boolean> hasCommentLiveData;
     private LiveData<PagedList<CommentData>> comments;
 
-    public CommentViewModel(Retrofit retrofit, Locale locale, String username,
+    public CommentViewModel(Retrofit retrofit, Locale locale, String username) {
-                         CommentDataSource.OnCommentFetchedCallback onCommentFetchedCallback) {
+        commentDataSourceFactory = new CommentDataSourceFactory(retrofit, locale, username);
-        commentDataSourceFactory = new CommentDataSourceFactory(retrofit, locale, username, onCommentFetchedCallback);
 
         initialLoadingState = Transformations.switchMap(commentDataSourceFactory.getCommentDataSourceLiveData(),
-                (Function<CommentDataSource, LiveData<NetworkState>>) CommentDataSource::getInitialLoadStateLiveData);
+                CommentDataSource::getInitialLoadStateLiveData);
         paginationNetworkState = Transformations.switchMap(commentDataSourceFactory.getCommentDataSourceLiveData(),
-                (Function<CommentDataSource, LiveData<NetworkState>>) CommentDataSource::getPaginationNetworkStateLiveData);
+                CommentDataSource::getPaginationNetworkStateLiveData);
+        hasCommentLiveData = Transformations.switchMap(commentDataSourceFactory.getCommentDataSourceLiveData(),
+                CommentDataSource::hasPostLiveData);
         PagedList.Config pagedListConfig =
                 (new PagedList.Config.Builder())
                         .setEnablePlaceholders(false)
@@ -48,6 +49,10 @@ public class CommentViewModel extends ViewModel {
         return initialLoadingState;
     }
 
+    LiveData<Boolean> hasComment() {
+        return hasCommentLiveData;
+    }
+
     void refresh() {
         commentDataSourceFactory.getCommentDataSource().invalidate();
     }
@@ -64,20 +69,17 @@ public class CommentViewModel extends ViewModel {
         private Retrofit retrofit;
         private Locale locale;
         private String username;
-        private CommentDataSource.OnCommentFetchedCallback onCommentFetchedCallback;
 
-        public Factory(Retrofit retrofit, Locale locale, String username,
+        public Factory(Retrofit retrofit, Locale locale, String username) {
-                       CommentDataSource.OnCommentFetchedCallback onCommentFetchedCallback) {
             this.retrofit = retrofit;
             this.locale = locale;
             this.username = username;
-            this.onCommentFetchedCallback = onCommentFetchedCallback;
         }
 
         @NonNull
         @Override
         public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
-            return (T) new CommentViewModel(retrofit, locale, username, onCommentFetchedCallback);
+            return (T) new CommentViewModel(retrofit, locale, username);
         }
     }
 }

app/src/main/java/ml/docilealligator/infinityforreddit/CommentsListingFragment.java

@@ -78,30 +78,14 @@ public class CommentsListingFragment extends Fragment implements FragmentCommuni
 
         mCommentRecyclerView.setLayoutManager(new LinearLayoutManager(activity));
 
-        CommentViewModel.Factory factory;
         mAdapter = new CommentsListingRecyclerViewAdapter(activity, mOauthRetrofit,
                 getArguments().getString(EXTRA_ACCESS_TOKEN), () -> mCommentViewModel.retryLoadingMore());
 
         String username = getArguments().getString(EXTRA_USERNAME_KEY);
 
-        factory = new CommentViewModel.Factory(mRetrofit, getResources().getConfiguration().locale,
-                username, new CommentDataSource.OnCommentFetchedCallback() {
-            @Override
-            public void hasComment() {
-                mFetchCommentInfoLinearLayout.setVisibility(View.GONE);
-            }
-
-            @Override
-            public void noComment() {
-                mFetchCommentInfoLinearLayout.setOnClickListener(view -> {
-                    //Do nothing
-                });
-                showErrorView(R.string.no_posts);
-            }
-        });
-
         mCommentRecyclerView.setAdapter(mAdapter);
 
+        CommentViewModel.Factory factory = new CommentViewModel.Factory(mRetrofit, getResources().getConfiguration().locale, username);
         mCommentViewModel = ViewModelProviders.of(this, factory).get(CommentViewModel.class);
         mCommentViewModel.getComments().observe(this, comments -> mAdapter.submitList(comments));
 
@@ -117,6 +101,17 @@ public class CommentsListingFragment extends Fragment implements FragmentCommuni
             }
         });
 
+        mCommentViewModel.hasComment().observe(this, hasComment -> {
+            if(hasComment) {
+                mFetchCommentInfoLinearLayout.setVisibility(View.GONE);
+            } else {
+                mFetchCommentInfoLinearLayout.setOnClickListener(view -> {
+                    //Do nothing
+                });
+                showErrorView(R.string.no_comments);
+            }
+        });
+
         mCommentViewModel.getPaginationNetworkState().observe(this, networkState -> {
             mAdapter.setNetworkState(networkState);
         });

app/src/main/java/ml/docilealligator/infinityforreddit/MainActivity.java

@@ -150,6 +150,7 @@ public class MainActivity extends AppCompatActivity implements SortTypeBottomShe
             mProfileImageUrl = savedInstanceState.getString(ACCOUNT_PROFILE_IMAGE_URL_STATE);
             mBannerImageUrl = savedInstanceState.getString(ACCOUNT_BANNER_IMAGE_URL_STATE);
             mKarma = savedInstanceState.getInt(ACCOUNT_KARMA_STATE);
+
             if(!mNullAccessToken && mAccessToken == null) {
                 getCurrentAccountAndBindView();
             } else {

app/src/main/java/ml/docilealligator/infinityforreddit/PostDataSource.java

@@ -14,10 +14,6 @@ import retrofit2.Callback;
 import retrofit2.Retrofit;
 
 class PostDataSource extends PageKeyedDataSource<String, Post> {
-    interface OnPostFetchedCallback {
-        void hasPost();
-        void noPost();
-    }
 
     static final int TYPE_FRONT_PAGE = 0;
     static final int TYPE_SUBREDDIT = 1;
@@ -42,10 +38,10 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
     private int postType;
     private String sortType;
     private int filter;
-    private OnPostFetchedCallback onPostFetchedCallback;
 
     private MutableLiveData<NetworkState> paginationNetworkStateLiveData;
     private MutableLiveData<NetworkState> initialLoadStateLiveData;
+    private MutableLiveData<Boolean> hasPostLiveData;
 
     private LoadInitialParams<String> initialParams;
     private LoadInitialCallback<String, Post> initialCallback;
@@ -53,68 +49,72 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
     private LoadCallback<String, Post> callback;
 
     PostDataSource(Retrofit retrofit, String accessToken, Locale locale, int postType, String sortType,
-                   int filter, OnPostFetchedCallback onPostFetchedCallback) {
+                   int filter) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
         paginationNetworkStateLiveData = new MutableLiveData();
         initialLoadStateLiveData = new MutableLiveData();
+        hasPostLiveData = new MutableLiveData<>();
         this.postType = postType;
         this.sortType = sortType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
     PostDataSource(Retrofit retrofit, String accessToken, Locale locale, String subredditOrUserName, int postType,
-                   String sortType, int filter, OnPostFetchedCallback onPostFetchedCallback) {
+                   String sortType, int filter) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
         this.subredditOrUserName = subredditOrUserName;
-        paginationNetworkStateLiveData = new MutableLiveData();
+        paginationNetworkStateLiveData = new MutableLiveData<>();
-        initialLoadStateLiveData = new MutableLiveData();
+        initialLoadStateLiveData = new MutableLiveData<>();
+        hasPostLiveData = new MutableLiveData<>();
         this.postType = postType;
         this.sortType = sortType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
     PostDataSource(Retrofit retrofit, String accessToken, Locale locale, String subredditOrUserName, int postType,
-                   int filter, OnPostFetchedCallback onPostFetchedCallback) {
+                   int filter) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
         this.subredditOrUserName = subredditOrUserName;
-        paginationNetworkStateLiveData = new MutableLiveData();
+        paginationNetworkStateLiveData = new MutableLiveData<>();
-        initialLoadStateLiveData = new MutableLiveData();
+        initialLoadStateLiveData = new MutableLiveData<>();
+        hasPostLiveData = new MutableLiveData<>();
         this.postType = postType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
     PostDataSource(Retrofit retrofit, String accessToken, Locale locale, String subredditOrUserName, String query,
-                   int postType, String sortType, int filter, OnPostFetchedCallback onPostFetchedCallback) {
+                   int postType, String sortType, int filter) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
         this.subredditOrUserName = subredditOrUserName;
         this.query = query;
-        paginationNetworkStateLiveData = new MutableLiveData();
+        paginationNetworkStateLiveData = new MutableLiveData<>();
-        initialLoadStateLiveData = new MutableLiveData();
+        initialLoadStateLiveData = new MutableLiveData<>();
+        hasPostLiveData = new MutableLiveData<>();
         this.postType = postType;
         this.sortType = sortType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
-    MutableLiveData getPaginationNetworkStateLiveData() {
+    MutableLiveData<NetworkState> getPaginationNetworkStateLiveData() {
         return paginationNetworkStateLiveData;
     }
 
-    MutableLiveData getInitialLoadStateLiveData() {
+    MutableLiveData<NetworkState> getInitialLoadStateLiveData() {
         return initialLoadStateLiveData;
     }
 
+    MutableLiveData<Boolean> hasPostLiveData() {
+        return hasPostLiveData;
+    }
+
     @Override
     public void loadInitial(@NonNull LoadInitialParams<String> params, @NonNull final LoadInitialCallback<String, Post> callback) {
         initialParams = params;
@@ -184,7 +184,7 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
                             public void onParsePostSuccess(Post post) {
                                 ArrayList<Post> singlePostList = new ArrayList<>();
                                 singlePostList.add(post);
-                                onPostFetchedCallback.hasPost();
+                                hasPostLiveData.postValue(true);
                                 callback.onResult(singlePostList, null, null);
                                 initialLoadStateLiveData.postValue(NetworkState.LOADED);
                             }
@@ -208,12 +208,12 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
                                         }
 
                                         if(newPosts.size() != 0) {
-                                            onPostFetchedCallback.hasPost();
+                                            hasPostLiveData.postValue(true);
                                         } else if(nextPageKey != null) {
                                             loadBestPostsInitial(callback, nextPageKey);
                                             return;
                                         } else {
-                                            onPostFetchedCallback.noPost();
+                                            hasPostLiveData.postValue(false);
                                         }
 
                                         callback.onResult(newPosts, null, nextPageKey);
@@ -295,7 +295,7 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
                             public void onParsePostSuccess(Post post) {
                                 ArrayList<Post> singlePostList = new ArrayList<>();
                                 singlePostList.add(post);
-                                onPostFetchedCallback.hasPost();
+                                hasPostLiveData.postValue(true);
                                 callback.onResult(singlePostList, null, null);
                                 initialLoadStateLiveData.postValue(NetworkState.LOADED);
                             }
@@ -319,12 +319,12 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
                                         }
 
                                         if(newPosts.size() != 0) {
-                                            onPostFetchedCallback.hasPost();
+                                            hasPostLiveData.postValue(true);
                                         } else if(nextPageKey != null) {
                                             loadSubredditPostsInitial(callback, nextPageKey);
                                             return;
                                         } else {
-                                            onPostFetchedCallback.noPost();
+                                            hasPostLiveData.postValue(false);
                                         }
 
                                         callback.onResult(newPosts, null, nextPageKey);
@@ -411,12 +411,12 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
                                     }
 
                                     if(newPosts.size() != 0) {
-                                        onPostFetchedCallback.hasPost();
+                                        hasPostLiveData.postValue(true);
                                     } else if(nextPageKey != null) {
                                         loadUserPostsInitial(callback, nextPageKey);
                                         return;
                                     } else {
-                                        onPostFetchedCallback.noPost();
+                                        hasPostLiveData.postValue(false);
                                     }
 
                                     callback.onResult(newPosts, null, nextPageKey);
@@ -509,12 +509,12 @@ class PostDataSource extends PageKeyedDataSource<String, Post> {
                                     }
 
                                     if(newPosts.size() != 0) {
-                                        onPostFetchedCallback.hasPost();
+                                        hasPostLiveData.postValue(true);
                                     } else if(nextPageKey != null) {
                                         loadSearchPostsInitial(callback, nextPageKey);
                                         return;
                                     } else {
-                                        onPostFetchedCallback.noPost();
+                                        hasPostLiveData.postValue(false);
                                     }
 
                                     callback.onResult(newPosts, null, nextPageKey);

app/src/main/java/ml/docilealligator/infinityforreddit/PostDataSourceFactory.java

@@ -16,13 +16,12 @@ class PostDataSourceFactory extends DataSource.Factory {
     private int postType;
     private String sortType;
     private int filter;
-    private PostDataSource.OnPostFetchedCallback onPostFetchedCallback;
 
     private PostDataSource postDataSource;
     private MutableLiveData<PostDataSource> postDataSourceLiveData;
 
     PostDataSourceFactory(Retrofit retrofit, String accessToken, Locale locale, int postType, String sortType,
-                          int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                          int filter) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
@@ -30,12 +29,10 @@ class PostDataSourceFactory extends DataSource.Factory {
         this.postType = postType;
         this.sortType = sortType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
     PostDataSourceFactory(Retrofit retrofit, String accessToken, Locale locale, String subredditName,
-                          int postType, String sortType, int filter,
+                          int postType, String sortType, int filter) {
-                          PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
@@ -44,12 +41,10 @@ class PostDataSourceFactory extends DataSource.Factory {
         this.postType = postType;
         this.sortType = sortType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
     PostDataSourceFactory(Retrofit retrofit, String accessToken, Locale locale, String subredditName,
-                          int postType, int filter,
+                          int postType, int filter) {
-                          PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
@@ -57,12 +52,10 @@ class PostDataSourceFactory extends DataSource.Factory {
         postDataSourceLiveData = new MutableLiveData<>();
         this.postType = postType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
     PostDataSourceFactory(Retrofit retrofit, String accessToken, Locale locale, String subredditName,
-                          String query, int postType, String sortType, int filter,
+                          String query, int postType, String sortType, int filter) {
-                          PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.locale = locale;
@@ -72,23 +65,22 @@ class PostDataSourceFactory extends DataSource.Factory {
         this.postType = postType;
         this.sortType = sortType;
         this.filter = filter;
-        this.onPostFetchedCallback = onPostFetchedCallback;
     }
 
     @Override
     public DataSource create() {
         if(postType == PostDataSource.TYPE_FRONT_PAGE) {
             postDataSource = new PostDataSource(retrofit, accessToken, locale, postType, sortType,
-                    filter, onPostFetchedCallback);
+                    filter);
         } else if(postType == PostDataSource.TYPE_SEARCH) {
             postDataSource = new PostDataSource(retrofit, accessToken, locale, subredditName, query,
-                    postType, sortType, filter, onPostFetchedCallback);
+                    postType, sortType, filter);
         } else if(postType == PostDataSource.TYPE_SUBREDDIT) {
             postDataSource = new PostDataSource(retrofit, accessToken, locale, subredditName, postType,
-                    sortType, filter, onPostFetchedCallback);
+                    sortType, filter);
         } else {
             postDataSource = new PostDataSource(retrofit, accessToken, locale, subredditName, postType,
-                    filter, onPostFetchedCallback);
+                    filter);
         }
 
         postDataSourceLiveData.postValue(postDataSource);

app/src/main/java/ml/docilealligator/infinityforreddit/PostFragment.java

@@ -201,20 +201,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             });
 
             factory = new PostViewModel.Factory(mOauthRetrofit, accessToken,
-                    getResources().getConfiguration().locale, subredditName, query, postType, sortType, filter, new PostDataSource.OnPostFetchedCallback() {
+                    getResources().getConfiguration().locale, subredditName, query, postType, sortType, filter);
-                @Override
-                public void hasPost() {
-                    mFetchPostInfoLinearLayout.setVisibility(View.GONE);
-                }
-
-                @Override
-                public void noPost() {
-                    mFetchPostInfoLinearLayout.setOnClickListener(view -> {
-                        //Do nothing
-                    });
-                    showErrorView(R.string.no_posts);
-                }
-            });
         } else if(postType == PostDataSource.TYPE_SUBREDDIT) {
             String subredditName = getArguments().getString(EXTRA_NAME);
 
@@ -238,20 +225,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             });
 
             factory = new PostViewModel.Factory(mOauthRetrofit, accessToken,
-                    getResources().getConfiguration().locale, subredditName, postType, sortType, filter, new PostDataSource.OnPostFetchedCallback() {
+                    getResources().getConfiguration().locale, subredditName, postType, sortType, filter);
-                @Override
-                public void hasPost() {
-                    mFetchPostInfoLinearLayout.setVisibility(View.GONE);
-                }
-
-                @Override
-                public void noPost() {
-                    mFetchPostInfoLinearLayout.setOnClickListener(view -> {
-                        //Do nothing
-                    });
-                    showErrorView(R.string.no_posts);
-                }
-            });
         } else if(postType == PostDataSource.TYPE_USER) {
             CoordinatorLayout.LayoutParams params = (CoordinatorLayout.LayoutParams) mFetchPostInfoLinearLayout.getLayoutParams();
             params.height = ViewGroup.LayoutParams.WRAP_CONTENT;
@@ -278,21 +252,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             });
 
             factory = new PostViewModel.Factory(mOauthRetrofit, accessToken,
-                    getResources().getConfiguration().locale, username, postType, sortType, filter,
+                    getResources().getConfiguration().locale, username, postType, sortType, filter);
-                    new PostDataSource.OnPostFetchedCallback() {
-                @Override
-                public void hasPost() {
-                    mFetchPostInfoLinearLayout.setVisibility(View.GONE);
-                }
-
-                @Override
-                public void noPost() {
-                    mFetchPostInfoLinearLayout.setOnClickListener(view -> {
-                        //Do nothing
-                    });
-                    showErrorView(R.string.no_posts);
-                }
-            });
         } else {
             mAdapter = new PostRecyclerViewAdapter(activity, mOauthRetrofit, mRetrofit, redditDataRoomDatabase,
                     accessToken, postType, true, new PostRecyclerViewAdapter.Callback() {
@@ -313,20 +273,7 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             });
 
             factory = new PostViewModel.Factory(mOauthRetrofit, accessToken,
-                    getResources().getConfiguration().locale, postType, sortType, filter, new PostDataSource.OnPostFetchedCallback() {
+                    getResources().getConfiguration().locale, postType, sortType, filter);
-                @Override
-                public void hasPost() {
-                    mFetchPostInfoLinearLayout.setVisibility(View.GONE);
-                }
-
-                @Override
-                public void noPost() {
-                    mFetchPostInfoLinearLayout.setOnClickListener(view -> {
-                        //Do nothing
-                    });
-                    showErrorView(R.string.no_posts);
-                }
-            });
         }
 
         mPostRecyclerView.setAdapter(mAdapter);
@@ -346,6 +293,14 @@ public class PostFragment extends Fragment implements FragmentCommunicator {
             }
         });
 
+        mPostViewModel.hasPost().observe(this, hasPost -> {
+            if(hasPost) {
+                mFetchPostInfoLinearLayout.setVisibility(View.GONE);
+            } else {
+                showErrorView(R.string.no_posts);
+            }
+        });
+
         mPostViewModel.getPaginationNetworkState().observe(this, networkState -> {
             mAdapter.setNetworkState(networkState);
         });

app/src/main/java/ml/docilealligator/infinityforreddit/PostViewModel.java

@@ -1,7 +1,6 @@
 package ml.docilealligator.infinityforreddit;
 
 import androidx.annotation.NonNull;
-import androidx.arch.core.util.Function;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.Transformations;
@@ -18,17 +17,20 @@ public class PostViewModel extends ViewModel {
     private PostDataSourceFactory postDataSourceFactory;
     private LiveData<NetworkState> paginationNetworkState;
     private LiveData<NetworkState> initialLoadingState;
+    private LiveData<Boolean> hasPostLiveData;
     private LiveData<PagedList<Post>> posts;
     private MutableLiveData<String> sortTypeLiveData;
 
     public PostViewModel(Retrofit retrofit, String accessToken, Locale locale, int postType, String sortType,
-                         int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                         int filter) {
-        postDataSourceFactory = new PostDataSourceFactory(retrofit, accessToken, locale, postType, sortType, filter, onPostFetchedCallback);
+        postDataSourceFactory = new PostDataSourceFactory(retrofit, accessToken, locale, postType, sortType, filter);
 
         initialLoadingState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                (Function<PostDataSource, LiveData<NetworkState>>) PostDataSource::getInitialLoadStateLiveData);
+                PostDataSource::getInitialLoadStateLiveData);
         paginationNetworkState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                (Function<PostDataSource, LiveData<NetworkState>>) PostDataSource::getPaginationNetworkStateLiveData);
+                PostDataSource::getPaginationNetworkStateLiveData);
+        hasPostLiveData = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
+                PostDataSource::hasPostLiveData);
 
         sortTypeLiveData = new MutableLiveData<>();
         sortTypeLiveData.postValue(sortType);
@@ -46,14 +48,16 @@ public class PostViewModel extends ViewModel {
     }
 
     public PostViewModel(Retrofit retrofit, String accessToken, Locale locale, String subredditName, int postType,
-                         String sortType, int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                         String sortType, int filter) {
         postDataSourceFactory = new PostDataSourceFactory(retrofit, accessToken, locale, subredditName,
-                postType, sortType, filter, onPostFetchedCallback);
+                postType, sortType, filter);
 
         initialLoadingState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                (Function<PostDataSource, LiveData<NetworkState>>) PostDataSource::getInitialLoadStateLiveData);
+                PostDataSource::getInitialLoadStateLiveData);
         paginationNetworkState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                (Function<PostDataSource, LiveData<NetworkState>>) PostDataSource::getPaginationNetworkStateLiveData);
+                PostDataSource::getPaginationNetworkStateLiveData);
+        hasPostLiveData = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
+                PostDataSource::hasPostLiveData);
 
         sortTypeLiveData = new MutableLiveData<>();
         sortTypeLiveData.postValue(sortType);
@@ -71,14 +75,16 @@ public class PostViewModel extends ViewModel {
     }
 
     public PostViewModel(Retrofit retrofit, String accessToken, Locale locale, String subredditName, int postType,
-                         int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                         int filter) {
         postDataSourceFactory = new PostDataSourceFactory(retrofit, accessToken, locale, subredditName,
-                postType, filter, onPostFetchedCallback);
+                postType, filter);
 
         initialLoadingState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                dataSource -> dataSource.getInitialLoadStateLiveData());
+                PostDataSource::getInitialLoadStateLiveData);
         paginationNetworkState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                (Function<PostDataSource, LiveData<NetworkState>>) PostDataSource::getPaginationNetworkStateLiveData);
+                PostDataSource::getPaginationNetworkStateLiveData);
+        hasPostLiveData = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
+                PostDataSource::hasPostLiveData);
 
         PagedList.Config pagedListConfig =
                 (new PagedList.Config.Builder())
@@ -90,14 +96,16 @@ public class PostViewModel extends ViewModel {
     }
 
     public PostViewModel(Retrofit retrofit, String accessToken, Locale locale, String subredditName, String query,
-                         int postType, String sortType, int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                         int postType, String sortType, int filter) {
         postDataSourceFactory = new PostDataSourceFactory(retrofit, accessToken, locale, subredditName,
-                query, postType, sortType, filter, onPostFetchedCallback);
+                query, postType, sortType, filter);
 
         initialLoadingState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                dataSource -> dataSource.getInitialLoadStateLiveData());
+                PostDataSource::getInitialLoadStateLiveData);
         paginationNetworkState = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
-                dataSource -> dataSource.getPaginationNetworkStateLiveData());
+                PostDataSource::getPaginationNetworkStateLiveData);
+        hasPostLiveData = Transformations.switchMap(postDataSourceFactory.getPostDataSourceLiveData(),
+                PostDataSource::hasPostLiveData);
 
         sortTypeLiveData = new MutableLiveData<>();
         sortTypeLiveData.postValue(sortType);
@@ -126,6 +134,10 @@ public class PostViewModel extends ViewModel {
         return initialLoadingState;
     }
 
+    LiveData<Boolean> hasPost() {
+        return hasPostLiveData;
+    }
+
     void refresh() {
         postDataSourceFactory.getPostDataSource().invalidate();
     }
@@ -151,21 +163,19 @@ public class PostViewModel extends ViewModel {
         private int postType;
         private String sortType;
         private int filter;
-        private PostDataSource.OnPostFetchedCallback onPostFetchedCallback;
 
         public Factory(Retrofit retrofit, String accessToken, Locale locale, int postType, String sortType,
-                       int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                       int filter) {
             this.retrofit = retrofit;
             this.accessToken = accessToken;
             this.locale = locale;
             this.postType = postType;
             this.sortType = sortType;
             this.filter = filter;
-            this.onPostFetchedCallback = onPostFetchedCallback;
         }
 
         public Factory(Retrofit retrofit, String accessToken, Locale locale, String subredditName, int postType,
-                       String sortType, int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                       String sortType, int filter) {
             this.retrofit = retrofit;
             this.accessToken = accessToken;
             this.locale = locale;
@@ -173,22 +183,20 @@ public class PostViewModel extends ViewModel {
             this.postType = postType;
             this.sortType = sortType;
             this.filter = filter;
-            this.onPostFetchedCallback = onPostFetchedCallback;
         }
 
         public Factory(Retrofit retrofit, String accessToken, Locale locale, String subredditName, int postType,
-                       int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                       int filter) {
             this.retrofit = retrofit;
             this.accessToken = accessToken;
             this.locale = locale;
             this.subredditName = subredditName;
             this.postType = postType;
             this.filter = filter;
-            this.onPostFetchedCallback = onPostFetchedCallback;
         }
 
         public Factory(Retrofit retrofit, String accessToken, Locale locale, String subredditName, String query,
-                       int postType, String sortType, int filter, PostDataSource.OnPostFetchedCallback onPostFetchedCallback) {
+                       int postType, String sortType, int filter) {
             this.retrofit = retrofit;
             this.accessToken = accessToken;
             this.locale = locale;
@@ -197,20 +205,19 @@ public class PostViewModel extends ViewModel {
             this.postType = postType;
             this.sortType = sortType;
             this.filter = filter;
-            this.onPostFetchedCallback = onPostFetchedCallback;
         }
 
         @NonNull
         @Override
         public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
             if(postType == PostDataSource.TYPE_FRONT_PAGE) {
-                return (T) new PostViewModel(retrofit, accessToken, locale, postType, sortType, filter, onPostFetchedCallback);
+                return (T) new PostViewModel(retrofit, accessToken, locale, postType, sortType, filter);
             } else if(postType == PostDataSource.TYPE_SEARCH){
-                return (T) new PostViewModel(retrofit, accessToken, locale, subredditName, query, postType, sortType, filter, onPostFetchedCallback);
+                return (T) new PostViewModel(retrofit, accessToken, locale, subredditName, query, postType, sortType, filter);
             } else if(postType == PostDataSource.TYPE_SUBREDDIT) {
-                return (T) new PostViewModel(retrofit, accessToken, locale, subredditName, postType, sortType, filter, onPostFetchedCallback);
+                return (T) new PostViewModel(retrofit, accessToken, locale, subredditName, postType, sortType, filter);
             } else {
-                return (T) new PostViewModel(retrofit, accessToken, locale, subredditName, postType, filter, onPostFetchedCallback);
+                return (T) new PostViewModel(retrofit, accessToken, locale, subredditName, postType, filter);
             }
         }
     }

app/src/main/java/ml/docilealligator/infinityforreddit/SubredditListingDataSource.java

@@ -10,41 +10,41 @@ import SubredditDatabase.SubredditData;
 import retrofit2.Retrofit;
 
 public class SubredditListingDataSource extends PageKeyedDataSource<String, SubredditData> {
-    interface OnSubredditListingDataFetchedCallback {
+
-        void hasSubreddit();
-        void noSubreddit();
-    }
     private Retrofit retrofit;
     private String query;
     private String sortType;
-    private OnSubredditListingDataFetchedCallback onSubredditListingDataFetchedCallback;
 
     private MutableLiveData<NetworkState> paginationNetworkStateLiveData;
     private MutableLiveData<NetworkState> initialLoadStateLiveData;
+    private MutableLiveData<Boolean> hasSubredditLiveData;
 
     private LoadInitialParams<String> initialParams;
     private LoadInitialCallback<String, SubredditData> initialCallback;
     private LoadParams<String> params;
     private LoadCallback<String, SubredditData> callback;
 
-    SubredditListingDataSource(Retrofit retrofit, String query, String sortType,
+    SubredditListingDataSource(Retrofit retrofit, String query, String sortType) {
-                               OnSubredditListingDataFetchedCallback onSubredditListingDataFetchedCallback) {
         this.retrofit = retrofit;
         this.query = query;
         this.sortType = sortType;
-        this.onSubredditListingDataFetchedCallback = onSubredditListingDataFetchedCallback;
+        paginationNetworkStateLiveData = new MutableLiveData<>();
-        paginationNetworkStateLiveData = new MutableLiveData();
+        initialLoadStateLiveData = new MutableLiveData<>();
-        initialLoadStateLiveData = new MutableLiveData();
+        hasSubredditLiveData = new MutableLiveData<>();
     }
 
-    MutableLiveData getPaginationNetworkStateLiveData() {
+    MutableLiveData<NetworkState> getPaginationNetworkStateLiveData() {
         return paginationNetworkStateLiveData;
     }
 
-    MutableLiveData getInitialLoadStateLiveData() {
+    MutableLiveData<NetworkState> getInitialLoadStateLiveData() {
         return initialLoadStateLiveData;
     }
 
+    MutableLiveData<Boolean> hasSubredditLiveData() {
+        return hasSubredditLiveData;
+    }
+
     @Override
     public void loadInitial(@NonNull LoadInitialParams<String> params, @NonNull LoadInitialCallback<String, SubredditData> callback) {
         initialParams = params;
@@ -56,9 +56,9 @@ public class SubredditListingDataSource extends PageKeyedDataSource<String, Subr
             @Override
             public void onFetchSubredditListingDataSuccess(ArrayList<SubredditData> subredditData, String after) {
                 if(subredditData.size() == 0) {
-                    onSubredditListingDataFetchedCallback.noSubreddit();
+                    hasSubredditLiveData.postValue(false);
                 } else {
-                    onSubredditListingDataFetchedCallback.hasSubreddit();
+                    hasSubredditLiveData.postValue(true);
                 }
 
                 callback.onResult(subredditData, null, after);
@@ -82,7 +82,7 @@ public class SubredditListingDataSource extends PageKeyedDataSource<String, Subr
         this.params = params;
         this.callback = callback;
 
-        if(params.key.equals("null")) {
+        if(params.key.equals("") || params.key.equals("null")) {
             return;
         }
 

app/src/main/java/ml/docilealligator/infinityforreddit/SubredditListingDataSourceFactory.java

@@ -9,25 +9,21 @@ public class SubredditListingDataSourceFactory extends DataSource.Factory {
     private Retrofit retrofit;
     private String query;
     private String sortType;
-    private SubredditListingDataSource.OnSubredditListingDataFetchedCallback onSubredditListingDataFetchedCallback;
 
     private SubredditListingDataSource subredditListingDataSource;
     private MutableLiveData<SubredditListingDataSource> subredditListingDataSourceMutableLiveData;
 
-    SubredditListingDataSourceFactory(Retrofit retrofit, String query, String sortType,
+    SubredditListingDataSourceFactory(Retrofit retrofit, String query, String sortType) {
-                                      SubredditListingDataSource.OnSubredditListingDataFetchedCallback onSubredditListingDataFetchedCallback) {
         this.retrofit = retrofit;
         this.query = query;
         this.sortType = sortType;
-        this.onSubredditListingDataFetchedCallback = onSubredditListingDataFetchedCallback;
         subredditListingDataSourceMutableLiveData = new MutableLiveData<>();
     }
 
     @NonNull
     @Override
     public DataSource create() {
-        subredditListingDataSource = new SubredditListingDataSource(retrofit,
+        subredditListingDataSource = new SubredditListingDataSource(retrofit, query, sortType);
-                query, sortType, onSubredditListingDataFetchedCallback);
         subredditListingDataSourceMutableLiveData.postValue(subredditListingDataSource);
         return subredditListingDataSource;
     }

app/src/main/java/ml/docilealligator/infinityforreddit/SubredditListingFragment.java

@@ -86,24 +86,8 @@ public class SubredditListingFragment extends Fragment implements FragmentCommun
         String accessToken = getArguments().getString(EXTRA_ACCESS_TOKEN);
         String accountName = getArguments().getString(EXTRA_ACCOUNT_NAME);
 
-        SubredditListingViewModel.Factory factory = new SubredditListingViewModel.Factory(mRetrofit, query,
-                PostDataSource.SORT_TYPE_RELEVANCE, new SubredditListingDataSource.OnSubredditListingDataFetchedCallback() {
-            @Override
-            public void hasSubreddit() {
-                mFetchSubredditListingInfoLinearLayout.setVisibility(View.GONE);
-            }
-
-            @Override
-            public void noSubreddit() {
-                mFetchSubredditListingInfoLinearLayout.setOnClickListener(view -> {
-                    //Do nothing
-                });
-                showErrorView(R.string.no_subreddits);
-            }
-        });
-
         mAdapter = new SubredditListingRecyclerViewAdapter(activity, mOauthRetrofit, mRetrofit,
-                accessToken, accountName, redditDataRoomDatabase.subscribedSubredditDao(),
+                accessToken, accountName, redditDataRoomDatabase,
                 new SubredditListingRecyclerViewAdapter.Callback() {
                     @Override
                     public void retryLoadingMore() {
@@ -124,6 +108,8 @@ public class SubredditListingFragment extends Fragment implements FragmentCommun
 
         mSubredditListingRecyclerView.setAdapter(mAdapter);
 
+        SubredditListingViewModel.Factory factory = new SubredditListingViewModel.Factory(mRetrofit, query,
+                PostDataSource.SORT_TYPE_RELEVANCE);
         mSubredditListingViewModel = ViewModelProviders.of(this, factory).get(SubredditListingViewModel.class);
         mSubredditListingViewModel.getSubreddits().observe(this, subredditData -> mAdapter.submitList(subredditData));
 
@@ -139,6 +125,17 @@ public class SubredditListingFragment extends Fragment implements FragmentCommun
             }
         });
 
+        mSubredditListingViewModel.hasSubredditLiveData().observe(this, hasSubreddit -> {
+            if(hasSubreddit) {
+                mFetchSubredditListingInfoLinearLayout.setVisibility(View.GONE);
+            } else {
+                mFetchSubredditListingInfoLinearLayout.setOnClickListener(view -> {
+                    //Do nothing
+                });
+                showErrorView(R.string.no_subreddits);
+            }
+        });
+
         mSubredditListingViewModel.getPaginationNetworkState().observe(this, networkState -> {
             mAdapter.setNetworkState(networkState);
         });

app/src/main/java/ml/docilealligator/infinityforreddit/SubredditListingRecyclerViewAdapter.java

@@ -21,7 +21,6 @@ import com.bumptech.glide.RequestManager;
 import com.bumptech.glide.request.RequestOptions;
 
 import SubredditDatabase.SubredditData;
-import SubscribedSubredditDatabase.SubscribedSubredditDao;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import jp.wasabeef.glide.transformations.RoundedCornersTransformation;
@@ -45,14 +44,14 @@ public class SubredditListingRecyclerViewAdapter extends PagedListAdapter<Subred
     private Retrofit retrofit;
     private String accessToken;
     private String accountName;
-    private SubscribedSubredditDao subscribedSubredditDao;
+    private RedditDataRoomDatabase redditDataRoomDatabase;
 
     private NetworkState networkState;
     private Callback callback;
 
     SubredditListingRecyclerViewAdapter(Context context, Retrofit oauthRetrofit, Retrofit retrofit,
                                         String accessToken, String accountName,
-                                        SubscribedSubredditDao subscribedSubredditDao,
+                                        RedditDataRoomDatabase redditDataRoomDatabase,
                                         Callback callback) {
         super(DIFF_CALLBACK);
         this.context = context;
@@ -60,7 +59,7 @@ public class SubredditListingRecyclerViewAdapter extends PagedListAdapter<Subred
         this.retrofit = retrofit;
         this.accessToken = accessToken;
         this.accountName = accountName;
-        this.subscribedSubredditDao = subscribedSubredditDao;
+        this.redditDataRoomDatabase = redditDataRoomDatabase;
         this.callback = callback;
         glide = Glide.with(context.getApplicationContext());
     }
@@ -113,7 +112,7 @@ public class SubredditListingRecyclerViewAdapter extends PagedListAdapter<Subred
 
             ((DataViewHolder) holder).subredditNameTextView.setText(subredditData.getName());
 
-            new CheckIsSubscribedToSubredditAsyncTask(subscribedSubredditDao, subredditData.getName(), accountName,
+            new CheckIsSubscribedToSubredditAsyncTask(redditDataRoomDatabase, subredditData.getName(), accountName,
                     new CheckIsSubscribedToSubredditAsyncTask.CheckIsSubscribedToSubredditListener() {
                         @Override
                         public void isSubscribed() {
@@ -125,7 +124,7 @@ public class SubredditListingRecyclerViewAdapter extends PagedListAdapter<Subred
                             ((DataViewHolder) holder).subscribeButton.setVisibility(View.VISIBLE);
                             ((DataViewHolder) holder).subscribeButton.setOnClickListener(view -> {
                                 SubredditSubscription.subscribeToSubreddit(oauthRetrofit, retrofit,
-                                        accessToken, accountName, subredditData.getName(), subscribedSubredditDao,
+                                        accessToken, accountName, subredditData.getName(), redditDataRoomDatabase,
                                         new SubredditSubscription.SubredditSubscriptionListener() {
                                             @Override
                                             public void onSubredditSubscriptionSuccess() {

app/src/main/java/ml/docilealligator/infinityforreddit/SubredditListingViewModel.java

@@ -1,7 +1,6 @@
 package ml.docilealligator.infinityforreddit;
 
 import androidx.annotation.NonNull;
-import androidx.arch.core.util.Function;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.Transformations;
@@ -17,17 +16,19 @@ public class SubredditListingViewModel extends ViewModel {
     private SubredditListingDataSourceFactory subredditListingDataSourceFactory;
     private LiveData<NetworkState> paginationNetworkState;
     private LiveData<NetworkState> initialLoadingState;
+    private LiveData<Boolean> hasSubredditLiveData;
     private LiveData<PagedList<SubredditData>> subreddits;
     private MutableLiveData<String> sortTypeLiveData;
 
-    SubredditListingViewModel(Retrofit retrofit, String query, String sortType,
+    SubredditListingViewModel(Retrofit retrofit, String query, String sortType) {
-                              SubredditListingDataSource.OnSubredditListingDataFetchedCallback onSubredditListingDataFetchedCallback) {
+        subredditListingDataSourceFactory = new SubredditListingDataSourceFactory(retrofit, query, sortType);
-        subredditListingDataSourceFactory = new SubredditListingDataSourceFactory(retrofit, query, sortType, onSubredditListingDataFetchedCallback);
 
         initialLoadingState = Transformations.switchMap(subredditListingDataSourceFactory.getSubredditListingDataSourceMutableLiveData(),
-                (Function<SubredditListingDataSource, LiveData<NetworkState>>) SubredditListingDataSource::getInitialLoadStateLiveData);
+                SubredditListingDataSource::getInitialLoadStateLiveData);
         paginationNetworkState = Transformations.switchMap(subredditListingDataSourceFactory.getSubredditListingDataSourceMutableLiveData(),
-                (Function<SubredditListingDataSource, LiveData<NetworkState>>) SubredditListingDataSource::getPaginationNetworkStateLiveData);
+                SubredditListingDataSource::getPaginationNetworkStateLiveData);
+        hasSubredditLiveData = Transformations.switchMap(subredditListingDataSourceFactory.getSubredditListingDataSourceMutableLiveData(),
+                SubredditListingDataSource::hasSubredditLiveData);
 
         sortTypeLiveData = new MutableLiveData<>();
         sortTypeLiveData.postValue(sortType);
@@ -56,6 +57,10 @@ public class SubredditListingViewModel extends ViewModel {
         return initialLoadingState;
     }
 
+    LiveData<Boolean> hasSubredditLiveData() {
+        return hasSubredditLiveData;
+    }
+
     void refresh() {
         subredditListingDataSourceFactory.getSubredditListingDataSource().invalidate();
     }
@@ -76,20 +81,17 @@ public class SubredditListingViewModel extends ViewModel {
         private Retrofit retrofit;
         private String query;
         private String sortType;
-        private SubredditListingDataSource.OnSubredditListingDataFetchedCallback onSubredditListingDataFetchedCallback;
 
-        public Factory(Retrofit retrofit, String query, String sortType,
+        public Factory(Retrofit retrofit, String query, String sortType) {
-                       SubredditListingDataSource.OnSubredditListingDataFetchedCallback onSubredditListingDataFetchedCallback) {
             this.retrofit = retrofit;
             this.query = query;
             this.sortType = sortType;
-            this.onSubredditListingDataFetchedCallback = onSubredditListingDataFetchedCallback;
         }
 
         @NonNull
         @Override
         public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
-            return (T) new SubredditListingViewModel(retrofit, query, sortType, onSubredditListingDataFetchedCallback);
+            return (T) new SubredditListingViewModel(retrofit, query, sortType);
         }
     }
 }

app/src/main/java/ml/docilealligator/infinityforreddit/SubredditSubscription.java

@@ -9,7 +9,6 @@ import java.util.HashMap;
 import java.util.Map;
 
 import SubredditDatabase.SubredditData;
-import SubscribedSubredditDatabase.SubscribedSubredditDao;
 import SubscribedSubredditDatabase.SubscribedSubredditData;
 import retrofit2.Call;
 import retrofit2.Callback;
@@ -23,23 +22,23 @@ class SubredditSubscription {
 
     static void subscribeToSubreddit(Retrofit oauthRetrofit, Retrofit retrofit,
                                      String accessToken, String subredditName, String accountName,
-                                     SubscribedSubredditDao subscribedSubredditDao,
+                                     RedditDataRoomDatabase redditDataRoomDatabase,
                                      SubredditSubscriptionListener subredditSubscriptionListener) {
         subredditSubscription(oauthRetrofit, retrofit, accessToken, subredditName, accountName, "sub",
-                subscribedSubredditDao, subredditSubscriptionListener);
+                redditDataRoomDatabase, subredditSubscriptionListener);
     }
 
     static void unsubscribeToSubreddit(Retrofit oauthRetrofit, String accessToken,
                                        String subredditName, String accountName,
-                                       SubscribedSubredditDao subscribedSubredditDao,
+                                       RedditDataRoomDatabase redditDataRoomDatabase,
                                        SubredditSubscriptionListener subredditSubscriptionListener) {
         subredditSubscription(oauthRetrofit, null, accessToken, subredditName, accountName, "unsub",
-                subscribedSubredditDao,subredditSubscriptionListener);
+                redditDataRoomDatabase,subredditSubscriptionListener);
     }
 
     private static void subredditSubscription(Retrofit oauthRetrofit, Retrofit retrofit, String accessToken,
                                               String subredditName, String accountName, String action,
-                                              SubscribedSubredditDao subscribedSubredditDao,
+                                              RedditDataRoomDatabase redditDataRoomDatabase,
                                               SubredditSubscriptionListener subredditSubscriptionListener) {
         RedditAPI api = oauthRetrofit.create(RedditAPI.class);
 
@@ -56,7 +55,7 @@ class SubredditSubscription {
                         FetchSubredditData.fetchSubredditData(retrofit, subredditName, new FetchSubredditData.FetchSubredditDataListener() {
                             @Override
                             public void onFetchSubredditDataSuccess(SubredditData subredditData, int nCurrentOnlineSubscribers) {
-                                new UpdateSubscriptionAsyncTask(subscribedSubredditDao,
+                                new UpdateSubscriptionAsyncTask(redditDataRoomDatabase,
                                         subredditData, accountName, true).execute();
                             }
 
@@ -66,7 +65,7 @@ class SubredditSubscription {
                             }
                         });
                     } else {
-                        new UpdateSubscriptionAsyncTask(subscribedSubredditDao, subredditName, accountName, false).execute();
+                        new UpdateSubscriptionAsyncTask(redditDataRoomDatabase, subredditName, accountName, false).execute();
                     }
                     subredditSubscriptionListener.onSubredditSubscriptionSuccess();
                 } else {
@@ -85,23 +84,23 @@ class SubredditSubscription {
 
     private static class UpdateSubscriptionAsyncTask extends AsyncTask<Void, Void, Void> {
 
-        private SubscribedSubredditDao subscribedSubredditDao;
+        private RedditDataRoomDatabase redditDataRoomDatabase;
         private String subredditName;
         private String accountName;
         private SubscribedSubredditData subscribedSubredditData;
         private boolean isSubscribing;
 
-        UpdateSubscriptionAsyncTask(SubscribedSubredditDao subscribedSubredditDao, String subredditName,
+        UpdateSubscriptionAsyncTask(RedditDataRoomDatabase redditDataRoomDatabase, String subredditName,
                                     String accountName, boolean isSubscribing) {
-            this.subscribedSubredditDao = subscribedSubredditDao;
+            this.redditDataRoomDatabase = redditDataRoomDatabase;
             this.subredditName = subredditName;
             this.accountName = accountName;
             this.isSubscribing = isSubscribing;
         }
 
-        UpdateSubscriptionAsyncTask(SubscribedSubredditDao subscribedSubredditDao, SubredditData subredditData,
+        UpdateSubscriptionAsyncTask(RedditDataRoomDatabase redditDataRoomDatabase, SubredditData subredditData,
                                     String accountName, boolean isSubscribing) {
-            this.subscribedSubredditDao = subscribedSubredditDao;
+            this.redditDataRoomDatabase = redditDataRoomDatabase;
             this.subscribedSubredditData = new SubscribedSubredditData(subredditData.getId(), subredditData.getName(),
                     subredditData.getIconUrl(), accountName);
             this.accountName = accountName;
@@ -111,9 +110,9 @@ class SubredditSubscription {
         @Override
         protected Void doInBackground(Void... voids) {
             if(isSubscribing) {
-                subscribedSubredditDao.insert(subscribedSubredditData);
+                redditDataRoomDatabase.subscribedSubredditDao().insert(subscribedSubredditData);
             } else {
-                subscribedSubredditDao.deleteSubscribedSubreddit(subredditName, accountName);
+                redditDataRoomDatabase.subscribedSubredditDao().deleteSubscribedSubreddit(subredditName, accountName);
             }
             return null;
         }

app/src/main/java/ml/docilealligator/infinityforreddit/UserListingDataSource.java

@@ -10,42 +10,41 @@ import User.UserData;
 import retrofit2.Retrofit;
 
 public class UserListingDataSource extends PageKeyedDataSource<String, UserData> {
-    interface OnUserListingDataFetchedCallback {
-        void hasUser();
-        void noUser();
-    }
 
     private Retrofit retrofit;
     private String query;
     private String sortType;
-    private UserListingDataSource.OnUserListingDataFetchedCallback onUserListingDataFetchedCallback;
 
     private MutableLiveData<NetworkState> paginationNetworkStateLiveData;
     private MutableLiveData<NetworkState> initialLoadStateLiveData;
+    private MutableLiveData<Boolean> hasUserLiveData;
 
     private PageKeyedDataSource.LoadInitialParams<String> initialParams;
     private PageKeyedDataSource.LoadInitialCallback<String, UserData> initialCallback;
     private PageKeyedDataSource.LoadParams<String> params;
     private PageKeyedDataSource.LoadCallback<String, UserData> callback;
 
-    UserListingDataSource(Retrofit retrofit, String query, String sortType,
+    UserListingDataSource(Retrofit retrofit, String query, String sortType) {
-                               UserListingDataSource.OnUserListingDataFetchedCallback onUserListingDataFetchedCallback) {
         this.retrofit = retrofit;
         this.query = query;
         this.sortType = sortType;
-        this.onUserListingDataFetchedCallback = onUserListingDataFetchedCallback;
+        paginationNetworkStateLiveData = new MutableLiveData<>();
-        paginationNetworkStateLiveData = new MutableLiveData();
+        initialLoadStateLiveData = new MutableLiveData<>();
-        initialLoadStateLiveData = new MutableLiveData();
+        hasUserLiveData = new MutableLiveData<>();
     }
 
-    MutableLiveData getPaginationNetworkStateLiveData() {
+    MutableLiveData<NetworkState> getPaginationNetworkStateLiveData() {
         return paginationNetworkStateLiveData;
     }
 
-    MutableLiveData getInitialLoadStateLiveData() {
+    MutableLiveData<NetworkState> getInitialLoadStateLiveData() {
         return initialLoadStateLiveData;
     }
 
+    MutableLiveData<Boolean> hasUserLiveData() {
+        return hasUserLiveData;
+    }
+
     @Override
     public void loadInitial(@NonNull PageKeyedDataSource.LoadInitialParams<String> params, @NonNull PageKeyedDataSource.LoadInitialCallback<String, UserData> callback) {
         initialParams = params;
@@ -57,9 +56,9 @@ public class UserListingDataSource extends PageKeyedDataSource<String, UserData>
             @Override
             public void onFetchUserListingDataSuccess(ArrayList<UserData> UserData, String after) {
                 if(UserData.size() == 0) {
-                    onUserListingDataFetchedCallback.noUser();
+                    hasUserLiveData.postValue(false);
                 } else {
-                    onUserListingDataFetchedCallback.hasUser();
+                    hasUserLiveData.postValue(true);
                 }
 
                 callback.onResult(UserData, null, after);

app/src/main/java/ml/docilealligator/infinityforreddit/UserListingDataSourceFactory.java

@@ -9,25 +9,21 @@ public class UserListingDataSourceFactory extends DataSource.Factory {
     private Retrofit retrofit;
     private String query;
     private String sortType;
-    private UserListingDataSource.OnUserListingDataFetchedCallback onUserListingDataFetchedCallback;
 
     private UserListingDataSource userListingDataSource;
     private MutableLiveData<UserListingDataSource> userListingDataSourceMutableLiveData;
 
-    UserListingDataSourceFactory(Retrofit retrofit, String query, String sortType,
+    UserListingDataSourceFactory(Retrofit retrofit, String query, String sortType) {
-                                      UserListingDataSource.OnUserListingDataFetchedCallback onUserListingDataFetchedCallback) {
         this.retrofit = retrofit;
         this.query = query;
         this.sortType = sortType;
-        this.onUserListingDataFetchedCallback = onUserListingDataFetchedCallback;
         userListingDataSourceMutableLiveData = new MutableLiveData<>();
     }
 
     @NonNull
     @Override
     public DataSource create() {
-        userListingDataSource = new UserListingDataSource(retrofit,
+        userListingDataSource = new UserListingDataSource(retrofit, query, sortType);
-                query, sortType, onUserListingDataFetchedCallback);
         userListingDataSourceMutableLiveData.postValue(userListingDataSource);
         return userListingDataSource;
     }

app/src/main/java/ml/docilealligator/infinityforreddit/UserListingFragment.java

@@ -81,28 +81,14 @@ public class UserListingFragment extends Fragment implements FragmentCommunicato
         String accessToken = getArguments().getString(EXTRA_ACCESS_TOKEN);
         String accountName = getArguments().getString(EXTRA_ACCOUNT_NAME);
 
-        UserListingViewModel.Factory factory = new UserListingViewModel.Factory(mRetrofit, mQuery,
-                PostDataSource.SORT_TYPE_RELEVANCE, new UserListingDataSource.OnUserListingDataFetchedCallback() {
-                    @Override
-                    public void hasUser() {
-                        mFetchUserListingInfoLinearLayout.setVisibility(View.GONE);
-                    }
-
-                    @Override
-                    public void noUser() {
-                        mFetchUserListingInfoLinearLayout.setOnClickListener(view -> {
-                            //Do nothing
-                        });
-                        showErrorView(R.string.no_users);
-                    }
-                });
-
         mAdapter = new UserListingRecyclerViewAdapter(getActivity(), mOauthRetrofit, mRetrofit,
                 accessToken, accountName, redditDataRoomDatabase.subscribedUserDao(),
                 () -> mUserListingViewModel.retryLoadingMore());
 
         mUserListingRecyclerView.setAdapter(mAdapter);
 
+        UserListingViewModel.Factory factory = new UserListingViewModel.Factory(mRetrofit, mQuery,
+                PostDataSource.SORT_TYPE_RELEVANCE);
         mUserListingViewModel = ViewModelProviders.of(this, factory).get(UserListingViewModel.class);
         mUserListingViewModel.getUsers().observe(this, UserData -> mAdapter.submitList(UserData));
 
@@ -118,6 +104,17 @@ public class UserListingFragment extends Fragment implements FragmentCommunicato
             }
         });
 
+        mUserListingViewModel.hasUser().observe(this, hasUser -> {
+            if(hasUser) {
+                mFetchUserListingInfoLinearLayout.setVisibility(View.GONE);
+            } else {
+                mFetchUserListingInfoLinearLayout.setOnClickListener(view -> {
+                    //Do nothing
+                });
+                showErrorView(R.string.no_users);
+            }
+        });
+
         mUserListingViewModel.getPaginationNetworkState().observe(this, networkState -> {
             mAdapter.setNetworkState(networkState);
         });

app/src/main/java/ml/docilealligator/infinityforreddit/UserListingViewModel.java

@@ -1,7 +1,6 @@
 package ml.docilealligator.infinityforreddit;
 
 import androidx.annotation.NonNull;
-import androidx.arch.core.util.Function;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.MutableLiveData;
 import androidx.lifecycle.Transformations;
@@ -14,20 +13,22 @@ import User.UserData;
 import retrofit2.Retrofit;
 
 public class UserListingViewModel extends ViewModel {
-    private UserListingDataSourceFactory UserListingDataSourceFactory;
+    private UserListingDataSourceFactory userListingDataSourceFactory;
     private LiveData<NetworkState> paginationNetworkState;
     private LiveData<NetworkState> initialLoadingState;
+    private LiveData<Boolean> hasUserLiveData;
     private LiveData<PagedList<UserData>> users;
     private MutableLiveData<String> sortTypeLiveData;
 
-    UserListingViewModel(Retrofit retrofit, String query, String sortType,
+    UserListingViewModel(Retrofit retrofit, String query, String sortType) {
-                              UserListingDataSource.OnUserListingDataFetchedCallback onUserListingDataFetchedCallback) {
+        userListingDataSourceFactory = new UserListingDataSourceFactory(retrofit, query, sortType);
-        UserListingDataSourceFactory = new UserListingDataSourceFactory(retrofit, query, sortType, onUserListingDataFetchedCallback);
 
-        initialLoadingState = Transformations.switchMap(UserListingDataSourceFactory.getUserListingDataSourceMutableLiveData(),
+        initialLoadingState = Transformations.switchMap(userListingDataSourceFactory.getUserListingDataSourceMutableLiveData(),
-                (Function<UserListingDataSource, LiveData<NetworkState>>) UserListingDataSource::getInitialLoadStateLiveData);
+                UserListingDataSource::getInitialLoadStateLiveData);
-        paginationNetworkState = Transformations.switchMap(UserListingDataSourceFactory.getUserListingDataSourceMutableLiveData(),
+        paginationNetworkState = Transformations.switchMap(userListingDataSourceFactory.getUserListingDataSourceMutableLiveData(),
-                (Function<UserListingDataSource, LiveData<NetworkState>>) UserListingDataSource::getPaginationNetworkStateLiveData);
+                UserListingDataSource::getPaginationNetworkStateLiveData);
+        hasUserLiveData = Transformations.switchMap(userListingDataSourceFactory.getUserListingDataSourceMutableLiveData(),
+                UserListingDataSource::hasUserLiveData);
 
         sortTypeLiveData = new MutableLiveData<>();
         sortTypeLiveData.postValue(sortType);
@@ -39,8 +40,8 @@ public class UserListingViewModel extends ViewModel {
                         .build();
 
         users = Transformations.switchMap(sortTypeLiveData, sort -> {
-            UserListingDataSourceFactory.changeSortType(sortTypeLiveData.getValue());
+            userListingDataSourceFactory.changeSortType(sortTypeLiveData.getValue());
-            return (new LivePagedListBuilder(UserListingDataSourceFactory, pagedListConfig)).build();
+            return (new LivePagedListBuilder(userListingDataSourceFactory, pagedListConfig)).build();
         });
     }
 
@@ -56,16 +57,20 @@ public class UserListingViewModel extends ViewModel {
         return initialLoadingState;
     }
 
+    LiveData<Boolean> hasUser() {
+        return hasUserLiveData;
+    }
+
     void refresh() {
-        UserListingDataSourceFactory.getUserListingDataSource().invalidate();
+        userListingDataSourceFactory.getUserListingDataSource().invalidate();
     }
 
     void retry() {
-        UserListingDataSourceFactory.getUserListingDataSource().retry();
+        userListingDataSourceFactory.getUserListingDataSource().retry();
     }
 
     void retryLoadingMore() {
-        UserListingDataSourceFactory.getUserListingDataSource().retryLoadingMore();
+        userListingDataSourceFactory.getUserListingDataSource().retryLoadingMore();
     }
 
     void changeSortType(String sortType) {
@@ -76,20 +81,17 @@ public class UserListingViewModel extends ViewModel {
         private Retrofit retrofit;
         private String query;
         private String sortType;
-        private UserListingDataSource.OnUserListingDataFetchedCallback onUserListingDataFetchedCallback;
 
-        public Factory(Retrofit retrofit, String query, String sortType,
+        public Factory(Retrofit retrofit, String query, String sortType) {
-                       UserListingDataSource.OnUserListingDataFetchedCallback onUserListingDataFetchedCallback) {
             this.retrofit = retrofit;
             this.query = query;
             this.sortType = sortType;
-            this.onUserListingDataFetchedCallback = onUserListingDataFetchedCallback;
         }
 
         @NonNull
         @Override
         public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
-            return (T) new UserListingViewModel(retrofit, query, sortType, onUserListingDataFetchedCallback);
+            return (T) new UserListingViewModel(retrofit, query, sortType);
         }
     }
 }

app/src/main/java/ml/docilealligator/infinityforreddit/ViewSubredditDetailActivity.java

@@ -31,7 +31,6 @@ import javax.inject.Named;
 import SubredditDatabase.SubredditDao;
 import SubredditDatabase.SubredditData;
 import SubredditDatabase.SubredditViewModel;
-import SubscribedSubredditDatabase.SubscribedSubredditDao;
 import butterknife.BindView;
 import butterknife.ButterKnife;
 import jp.wasabeef.glide.transformations.RoundedCornersTransformation;
@@ -76,7 +75,6 @@ public class ViewSubredditDetailActivity extends AppCompatActivity implements So
     private PostTypeBottomSheetFragment postTypeBottomSheetFragment;
     private SortTypeBottomSheetFragment sortTypeBottomSheetFragment;
 
-    private SubscribedSubredditDao subscribedSubredditDao;
     private SubredditViewModel mSubredditViewModel;
 
     @Inject
@@ -142,7 +140,6 @@ public class ViewSubredditDetailActivity extends AppCompatActivity implements So
         ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams) toolbar.getLayoutParams();
         params.topMargin = statusBarHeight;
 
-        subscribedSubredditDao = mRedditDataRoomDatabase.subscribedSubredditDao();
         glide = Glide.with(this);
 
         mSubredditViewModel = ViewModelProviders.of(this,
@@ -239,7 +236,7 @@ public class ViewSubredditDetailActivity extends AppCompatActivity implements So
                 subscriptionReady = false;
                 if(subscribeSubredditChip.getText().equals(getResources().getString(R.string.subscribe))) {
                     SubredditSubscription.subscribeToSubreddit(mOauthRetrofit, mRetrofit, mAccessToken,
-                            subredditName, mAccountName, subscribedSubredditDao,
+                            subredditName, mAccountName, mRedditDataRoomDatabase,
                             new SubredditSubscription.SubredditSubscriptionListener() {
                                 @Override
                                 public void onSubredditSubscriptionSuccess() {
@@ -257,7 +254,7 @@ public class ViewSubredditDetailActivity extends AppCompatActivity implements So
                             });
                 } else {
                     SubredditSubscription.unsubscribeToSubreddit(mOauthRetrofit, mAccessToken,
-                            subredditName, mAccountName, subscribedSubredditDao,
+                            subredditName, mAccountName, mRedditDataRoomDatabase,
                             new SubredditSubscription.SubredditSubscriptionListener() {
                                 @Override
                                 public void onSubredditSubscriptionSuccess() {
@@ -277,7 +274,7 @@ public class ViewSubredditDetailActivity extends AppCompatActivity implements So
             }
         });
 
-        new CheckIsSubscribedToSubredditAsyncTask(subscribedSubredditDao, subredditName, mAccountName,
+        new CheckIsSubscribedToSubredditAsyncTask(mRedditDataRoomDatabase, subredditName, mAccountName,
                 new CheckIsSubscribedToSubredditAsyncTask.CheckIsSubscribedToSubredditListener() {
                     @Override
                     public void isSubscribed() {

app/src/main/java/ml/docilealligator/infinityforreddit/ViewUserDetailActivity.java

@@ -489,7 +489,6 @@ public class ViewUserDetailActivity extends AppCompatActivity {
                     break;
                 case 1:
                     commentsListingFragment = (CommentsListingFragment) fragment;
-                    break;
             }
             return fragment;
         }

app/src/main/res/layout/fragment_followed_users_listing.xml

@@ -27,7 +27,8 @@
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_marginTop="16dp"
-            android:gravity="center" />
+            android:gravity="center"
+            android:text="@string/no_users" />
 
     </LinearLayout>
 

app/src/main/res/layout/fragment_subscribed_subreddits_listing.xml

@@ -28,7 +28,7 @@
             android:layout_height="wrap_content"
             android:layout_marginTop="16dp"
             android:gravity="center"
-            android:text="@string/no_subreddits"/>
+            android:text="@string/no_subreddits" />
 
     </LinearLayout>
 

app/src/main/res/values/strings.xml

@@ -35,9 +35,10 @@
     <string name="load_posts_error">Error loading posts.\nTap to retry.</string>
     <string name="search_subreddits_error">Error searching subreddits.\nTap to retry.</string>
     <string name="search_users_error">Error searching users.\nTap to retry.</string>
-    <string name="no_posts">No posts found.</string>
+    <string name="no_posts">No posts found</string>
-    <string name="no_subreddits">No subreddits found.</string>
+    <string name="no_comments">No comments found</string>
-    <string name="no_users">No users found.</string>
+    <string name="no_subreddits">No subreddits found</string>
+    <string name="no_users">No users found</string>
     <string name="no_storage_permission">No storage permission to save this file</string>
 
     <string name="load_comments_failed">Error loading comments.</string>