Make CScreenSong, CSongFilter able to show only songs that are in

a specified playlist

VocaluxeLib/IBasic.cs

@@ -251,7 +251,7 @@ namespace VocaluxeLib
         void AddPartySongSung(int songID);
         void ResetSongSung(int catIndex = -1);
 
-        void SortSongs(ESongSorting sorting, EOffOn tabs, EOffOn ignoreArticles, String searchString, EDuetOptions duetOptions);
+        void SortSongs(ESongSorting sorting, EOffOn tabs, EOffOn ignoreArticles, String searchString, EDuetOptions duetOptions, int playlistID);
 
         void NextCategory();
         void PrevCategory();
@@ -325,6 +325,7 @@ namespace VocaluxeLib
 
         int GetSongCount(int playlistID);
         CPlaylistSong GetSong(int playlistID, int songIndex);
+        bool ContainsSong(int playlistID, int songIndex);
     }
 
     public interface IPreviewPlayer

VocaluxeLib/PartyModes/CPartyModeNormal.cs

@@ -67,6 +67,7 @@ namespace VocaluxeLib.PartyModes
             _ScreenSongOptions.Sorting.SearchString = String.Empty;
             _ScreenSongOptions.Sorting.SearchActive = false;
             _ScreenSongOptions.Sorting.DuetOptions = EDuetOptions.All;
+            _ScreenSongOptions.Sorting.FilterPlaylistID = -1;
         }
 
         public override bool Init()

VocaluxeLib/PartyModes/IPartyMode.cs

@@ -34,6 +34,7 @@ namespace VocaluxeLib.PartyModes
         public EOffOn IgnoreArticles;
         public string SearchString;
         public bool SearchActive;
+        public int FilterPlaylistID; //show only songs that are in this playlist, -1 for all songs
         public EDuetOptions DuetOptions;
     }