/// <summary>
        /// Called when the active button is changed.
        /// </summary>
        /// <param name="sender">The event source.</param>
        /// <param name="e">The event data.</param>
        protected virtual void OnIsActiveChanged(object sender, RoutedEventArgs e)
        {
            FrameworkElement?Element = sender as FrameworkElement;

            while (Element != null)
            {
                if (Element is ToolBarTray AsToolBarTray)
                {
                    PrettyItemsControl.MakeToolBarTrayPretty(AsToolBarTray);
                    break;
                }

                Element = Element.Parent as FrameworkElement;
            }
        }
 /// <summary>
 /// Called when the main toolbar is loaded.
 /// </summary>
 /// <param name="sender">The event source.</param>
 /// <param name="e">The event data.</param>
 private void OnMainToolBarLoaded(object sender, RoutedEventArgs e)
 {
     NotifyMainToolBarLoaded(e);
     PrettyItemsControl.MakeToolBarTrayPretty((ToolBarTray)sender);
 }