Fixed an issue where playlists weren't updated, leading to crashes.

The playlist observable doesn't seem to update when a change occurs (perhaps SqlBrite isn't being notified of change by the underlying content provider). Use our own ContentObserver to trigger updates. This ensures playlists are up-to-date, so the option to add to a previously deleted playlist no longer exists.

Author: timusus

app/src/main/java/com/simplecity/amp_library/utils/DataManager.java

@@ -1,5 +1,11 @@
 package com.simplecity.amp_library.utils;
 
+import android.annotation.SuppressLint;
+import android.database.ContentObserver;
+import android.net.Uri;
+import android.os.Handler;
+import android.os.Looper;
+import android.provider.MediaStore;
 import com.annimon.stream.Optional;
 import com.annimon.stream.Stream;
 import com.annimon.stream.function.Predicate;
@@ -17,6 +23,8 @@
 import com.squareup.sqlbrite2.SqlBrite;
 import io.reactivex.Observable;
 import io.reactivex.ObservableTransformer;
+import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.annotations.Nullable;
 import io.reactivex.disposables.Disposable;
 import io.reactivex.schedulers.Schedulers;
 import java.util.ArrayList;
@@ -67,6 +75,26 @@ public static DataManager getInstance() {
 
     private DataManager() {
 
+        ShuttleApplication.getInstance()
+                .getContentResolver()
+                .registerContentObserver(MediaStore.Audio.Playlists.EXTERNAL_CONTENT_URI, true, new ContentObserver(new Handler(Looper.getMainLooper())) {
+                    @Override
+                    public void onChange(boolean selfChange) {
+                        onChange(selfChange, null);
+                    }
+
+                    @SuppressLint("CheckResult")
+                    @Override
+                    public void onChange(boolean selfChange, @Nullable Uri uri) {
+                        SqlBriteUtils.createObservableList(ShuttleApplication.getInstance(), Playlist::new, Playlist.getQuery())
+                                .first(Collections.emptyList())
+                                .subscribeOn(AndroidSchedulers.mainThread())
+                                .subscribe(
+                                        playlists -> playlistsRelay.accept(playlists),
+                                        throwable -> LogUtils.logException(TAG, "Failed to update playlist relay", throwable)
+                                );
+                    }
+                });
     }
 
     public Observable<List<Song>> getAllSongsRelay() {

app/src/main/java/com/simplecity/amp_library/utils/PlaylistUtils.java

@@ -237,12 +237,14 @@ private static Completable createPlaylistMenu(SubMenu subMenu, boolean autoUpdat
                 .getPlaylistsRelay()
                 .take(autoUpdate ? Long.MAX_VALUE : 1)
                 .doOnNext(playlists -> {
-                    subMenu.clear();
-                    subMenu.add(0, MediaManager.Defs.NEW_PLAYLIST, 0, R.string.new_playlist);
-                    for (Playlist playlist : playlists) {
-                        final Intent intent = new Intent();
-                        intent.putExtra(ARG_PLAYLIST, playlist);
-                        subMenu.add(0, MediaManager.Defs.PLAYLIST_SELECTED, 0, playlist.name).setIntent(intent);
+                    if (subMenu != null) {
+                        subMenu.clear();
+                        subMenu.add(0, MediaManager.Defs.NEW_PLAYLIST, 0, R.string.new_playlist);
+                        for (Playlist playlist : playlists) {
+                            final Intent intent = new Intent();
+                            intent.putExtra(ARG_PLAYLIST, playlist);
+                            subMenu.add(0, MediaManager.Defs.PLAYLIST_SELECTED, 0, playlist.name).setIntent(intent);
+                        }
                     }
                 })
                 .ignoreElements()