Add abstract methods in PlaylistLocalItem & rename setIsModified

app/src/main/java/org/schabi/newpipe/database/playlist/PlaylistLocalItem.java

@@ -13,6 +13,10 @@ public interface PlaylistLocalItem extends LocalItem {
 
     long getDisplayIndex();
 
+    long getUid();
+
+    void setDisplayIndex(long displayIndex);
+
     /**
      * Merge localPlaylists and remotePlaylists by the display index.
      * If two items have the same display index, sort them in {@code CASE_INSENSITIVE_ORDER}.

app/src/main/java/org/schabi/newpipe/database/playlist/PlaylistMetadataEntry.java

@@ -11,13 +11,13 @@ public class PlaylistMetadataEntry implements PlaylistLocalItem {
     public static final String PLAYLIST_STREAM_COUNT = "streamCount";
 
     @ColumnInfo(name = PLAYLIST_ID)
-    public final long uid;
+    private final long uid;
     @ColumnInfo(name = PLAYLIST_NAME)
     public final String name;
     @ColumnInfo(name = PLAYLIST_THUMBNAIL_URL)
     public final String thumbnailUrl;
     @ColumnInfo(name = PLAYLIST_DISPLAY_INDEX)
-    public long displayIndex;
+    private long displayIndex;
     @ColumnInfo(name = PLAYLIST_STREAM_COUNT)
     public final long streamCount;
 
@@ -44,4 +44,14 @@ public class PlaylistMetadataEntry implements PlaylistLocalItem {
     public long getDisplayIndex() {
         return displayIndex;
     }
+
+    @Override
+    public long getUid() {
+        return uid;
+    }
+
+    @Override
+    public void setDisplayIndex(final long displayIndex) {
+        this.displayIndex = displayIndex;
+    }
 }

app/src/main/java/org/schabi/newpipe/database/playlist/model/PlaylistEntity.java

@@ -41,10 +41,10 @@ public class PlaylistEntity {
 
     @Ignore
     public PlaylistEntity(final PlaylistMetadataEntry item) {
-        this.uid = item.uid;
+        this.uid = item.getUid();
         this.name = item.name;
         this.thumbnailUrl = item.thumbnailUrl;
-        this.displayIndex = item.displayIndex;
+        this.displayIndex = item.getDisplayIndex();
     }
 
     public long getUid() {

app/src/main/java/org/schabi/newpipe/database/playlist/model/PlaylistRemoteEntity.java

@@ -105,6 +105,7 @@ public class PlaylistRemoteEntity implements PlaylistLocalItem {
                 && TextUtils.equals(getUploader(), info.getUploaderName());
     }
 
+    @Override
     public long getUid() {
         return uid;
     }
@@ -158,6 +159,7 @@ public class PlaylistRemoteEntity implements PlaylistLocalItem {
         return displayIndex;
     }
 
+    @Override
     public void setDisplayIndex(final long displayIndex) {
         this.displayIndex = displayIndex;
     }