private void SearchClick(object sender, RoutedEventArgs e)
        {
            foreach (CollectionItem item in items)
            {
                item.Visibility = string.IsNullOrWhiteSpace(tbSearch.Text) ? Visibility.Visible : (manager.MatchSearch(item, tbSearch.Text) ? Visibility.Visible : Visibility.Collapsed);
            }

            pnlSearch.BorderBrush = new SolidColorBrush(string.IsNullOrWhiteSpace(tbSearch.Text) ? Color.FromRgb(171, 173, 179) : Colors.Green);
        }