public bool Previous() { if (RepeatMode.Equals(GroupRepeatMode.RepeatOne)) { LastChange = DateTime.UtcNow; return(true); } PlayingItemIndex--; if (PlayingItemIndex < 0) { if (RepeatMode.Equals(GroupRepeatMode.RepeatAll)) { PlayingItemIndex = SortedPlaylist.Count - 1; } else { PlayingItemIndex = 0; return(false); } } LastChange = DateTime.UtcNow; return(true); }