Fix initialization of mutableLiveData in repository

.idea/misc.xml

@@ -8,6 +8,7 @@
         <entry key="app/src/main/res/drawable-v24/ic_launcher_foreground.xml" value="0.2814814814814815" />
         <entry key="app/src/main/res/drawable-v24/ic_shuffle.xml" value="0.28055555555555556" />
         <entry key="app/src/main/res/drawable/dialog_shape.xml" value="0.27685185185185185" />
+        <entry key="app/src/main/res/drawable/ic_arrow_back.xml" value="0.28055555555555556" />
         <entry key="app/src/main/res/drawable/ic_close.xml" value="0.27685185185185185" />
         <entry key="app/src/main/res/drawable/ic_done.xml" value="0.28055555555555556" />
         <entry key="app/src/main/res/drawable/ic_download_for_offline.xml" value="0.27685185185185185" />
@@ -40,7 +41,7 @@
         <entry key="app/src/main/res/layout/item_home_discovery_placeholder.xml" value="0.3229166666666667" />
         <entry key="app/src/main/res/layout/item_home_horizontal_placeholder.xml" value="0.3229166666666667" />
         <entry key="app/src/main/res/layout/item_home_placeholder.xml" value="0.47191011235955055" />
-        <entry key="app/src/main/res/layout/item_home_similar_track.xml" value="0.3229166666666667" />
+        <entry key="app/src/main/res/layout/item_home_similar_track.xml" value="0.7617554858934169" />
         <entry key="app/src/main/res/layout/item_home_track.xml" value="0.3229166666666667" />
         <entry key="app/src/main/res/layout/item_home_year.xml" value="0.3229166666666667" />
         <entry key="app/src/main/res/layout/item_home_year_placeholder.xml" value="0.3229166666666667" />

app/src/main/java/com/cappielloantonio/play/repository/ArtistRepository.java

@@ -31,7 +31,7 @@ public class ArtistRepository {
     }
 
     public MutableLiveData<List<Artist>> getStarredArtists() {
-        MutableLiveData<List<Artist>> starredArtists = new MutableLiveData<>(new ArrayList<>());
+        MutableLiveData<List<Artist>> starredArtists = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getAlbumSongListClient()
@@ -54,7 +54,7 @@ public class ArtistRepository {
     }
 
     public MutableLiveData<List<Artist>> getArtists(boolean random, int size) {
-        MutableLiveData<List<Artist>> listLiveArtists = new MutableLiveData<>(new ArrayList<>());
+        MutableLiveData<List<Artist>> listLiveArtists = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getBrowsingClient()
@@ -249,7 +249,7 @@ public class ArtistRepository {
     }
 
     public MutableLiveData<ArrayList<Song>> getArtistRandomSong(FragmentActivity fragmentActivity, Artist artist, int count) {
-        MutableLiveData<ArrayList<Song>> randomSongs = new MutableLiveData<>(new ArrayList());
+        MutableLiveData<ArrayList<Song>> randomSongs = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getBrowsingClient()
@@ -266,6 +266,7 @@ public class ArtistRepository {
                                 for (int index = 0; index < albums.size(); index++) {
                                     albumRepository.getAlbumTracks(albums.get(index).getId()).observe(fragmentActivity, songs -> {
                                         ArrayList<Song> liveSongs = randomSongs.getValue();
+                                        if(liveSongs == null) liveSongs = new ArrayList<>();
                                         Collections.shuffle(liveSongs);
                                         liveSongs.addAll(songs);
                                         randomSongs.setValue(liveSongs);
@@ -309,6 +310,7 @@ public class ArtistRepository {
 
     private void addToMutableLiveData(MutableLiveData<List<Artist>> liveData, Artist artist) {
         List<Artist> liveArtists = liveData.getValue();
+        if(liveArtists == null) liveArtists = new ArrayList<>();
         liveArtists.add(artist);
         liveData.setValue(liveArtists);
     }

app/src/main/java/com/cappielloantonio/play/repository/DownloadRepository.java

@@ -18,7 +18,6 @@ public class DownloadRepository {
     private static final String TAG = "QueueRepository";
 
     private DownloadDao downloadDao;
-    private MutableLiveData<List<Download>> listLiveDownload = new MutableLiveData<>(new ArrayList<>());
 
     public DownloadRepository(Application application) {
         AppDatabase database = AppDatabase.getInstance(application);

app/src/main/java/com/cappielloantonio/play/repository/PlaylistRepository.java

@@ -27,7 +27,7 @@ public class PlaylistRepository {
     }
 
     public MutableLiveData<List<Playlist>> getPlaylists(boolean random, int size) {
-        MutableLiveData<List<Playlist>> listLivePlaylists = new MutableLiveData<>(new ArrayList<>());
+        MutableLiveData<List<Playlist>> listLivePlaylists = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getPlaylistClient()
@@ -56,7 +56,7 @@ public class PlaylistRepository {
     }
 
     public MutableLiveData<List<Song>> getPlaylistSongs(String id) {
-        MutableLiveData<List<Song>> listLivePlaylistSongs = new MutableLiveData<>(new ArrayList<>());
+        MutableLiveData<List<Song>> listLivePlaylistSongs = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getPlaylistClient()

app/src/main/java/com/cappielloantonio/play/repository/SearchingRepository.java

@@ -111,7 +111,7 @@ public class SearchingRepository {
     }
 
     public MutableLiveData<List<String>> getSuggestions(String query) {
-        MutableLiveData<List<String>> suggestions = new MutableLiveData<>(new ArrayList());
+        MutableLiveData<List<String>> suggestions = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getSearchingClient()

app/src/main/java/com/cappielloantonio/play/repository/SongRepository.java

@@ -87,7 +87,7 @@ public class SongRepository {
     }
 
     public MutableLiveData<List<Song>> getRandomSample(int number, Integer fromYear, Integer toYear) {
-        MutableLiveData<List<Song>> randomSongsSample = new MutableLiveData<>(new ArrayList<>());
+        MutableLiveData<List<Song>> randomSongsSample = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getAlbumSongListClient()
@@ -180,7 +180,7 @@ public class SongRepository {
     }
 
     public MutableLiveData<List<Song>> getSongsByGenre(String id) {
-        MutableLiveData<List<Song>> songsByGenre = new MutableLiveData<>(new ArrayList<>());
+        MutableLiveData<List<Song>> songsByGenre = new MutableLiveData<>();
 
         App.getSubsonicClientInstance(application, false)
                 .getAlbumSongListClient()
@@ -192,6 +192,7 @@ public class SongRepository {
                             List<Song> newSongs = new ArrayList<>(MappingUtil.mapSong(response.body().getSongsByGenre().getSongs()));
                             List<Song> songs = songsByGenre.getValue();
 
+                            if(songs == null) songs = new ArrayList<>();
                             songs.addAll(newSongs);
                             Collections.shuffle(songs);
 
@@ -212,10 +213,9 @@ public class SongRepository {
     }
 
     public MutableLiveData<List<Song>> getSongsByGenres(ArrayList<String> genresId) {
-        MutableLiveData<List<Song>> songsByGenre = new MutableLiveData<>(new ArrayList<>());
+        MutableLiveData<List<Song>> songsByGenre = new MutableLiveData<>();
 
         for (String id : genresId)
-
             App.getSubsonicClientInstance(application, false)
                     .getAlbumSongListClient()
                     .getSongsByGenre(id, 500, 0)

app/src/main/java/com/cappielloantonio/play/viewmodel/AlbumCatalogueViewModel.java

@@ -45,6 +45,7 @@ public class AlbumCatalogueViewModel extends AndroidViewModel {
             @Override
             public void onLoadMedia(List<?> media) {
                 List<Album> liveAlbum = albumList.getValue();
+                if(liveAlbum == null) liveAlbum = new ArrayList<>();
                 liveAlbum.addAll(MappingUtil.mapAlbum((List<AlbumID3>) media));
                 albumList.setValue(liveAlbum);