private void Btn_Child_Click(object sender, RoutedEventArgs e)
        {
            Tbx_FilterId.Clear();

            buttonType = "CH";
            var lst = from b in App._bicycles where b.status == "Available" && b.category == "CH" select b;

            Lbx_Bicycles.ItemsSource = lst;
        }
        private void Btn_All_Click(object sender, RoutedEventArgs e)
        {
            Tbx_FilterId.Clear();

            buttonType = "All";

            var lst = from b in App._bicycles select b;

            Lbx_Bicycles.ItemsSource = lst;
        }