private void Header_Checked(object sender, RoutedEventArgs e)
        {
            foreach (UIElement element in Levels.Children)
            {
                if (element is LevelUserControl)
                {
                    LevelUserControl level = element as LevelUserControl;

                    level.Header.IsEnabled = true;
                }
            }
        }
        /// <summary>
        /// Insert a level radio button within the levels stack panel
        /// </summary>
        /// <param name="header">header of level</param>
        /// <param name="details">details of level</param>
        public void AddLevel(Level level)
        {
            LevelUserControl levelController = new LevelUserControl(level.Header, level.Details, Header.Content.ToString());

            //insert seperator between pairs of levels
            if (Levels.Children.Count > 0)
            {
                Separator sep = new Separator();
                sep.Height = 5;
                Levels.Children.Add(sep);
            }

            Levels.Children.Add(levelController);
        }