/// <summary>
        ///     After validating creates the Order and switches to viewing it
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Btn_Complete_Click(object sender, RoutedEventArgs e)
        {
            var ALL_VALUES_OK = true;

            if (!Check_CustomerForm())
            {
                ALL_VALUES_OK = false;
            }
            if (!Check_DetailsForm())
            {
                ALL_VALUES_OK = false;
            }
            if (!Has_Items_Selected())
            {
                ALL_VALUES_OK = false;
            }
            if (ALL_VALUES_OK)
            {
                var order = createOrderObject();
                OrderViewModel.insertOrder(order);
                MessageBox.Show("Order with ID " + order.idOrder + " was created.");
                orderMain.viewOrder(order.idOrder);
                Btn_clearAll_Click(null, null);
            }
        }
        /// <summary>
        ///     After validating updates the Order and switches to viewing it
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Btn_Complete_Click(object sender, RoutedEventArgs e)
        {
            var ALL_VALUES_OK = true;

            if (!Has_Items_Selected())
            {
                ALL_VALUES_OK = false;
            }
            if (ALL_VALUES_OK)
            {
                if (int.TryParse(txtBox_orderNumber.Text, out var n))
                {
                    OrderViewModel.updateOrder(createOrderObject(), order);
                    orderMain.viewOrder(order.idOrder);
                    Btn_clearAll_Click(null, null);
                }
            }
        }
 /// <summary>
 ///     Switches to view Order page and loads the specific order
 /// </summary>
 /// <param name="sender"></param>
 /// <param name="e"></param>
 private void ViewOrder_Click(object sender, RoutedEventArgs e)
 {
     orderMain.viewOrder(((Order)orderDataGrid.SelectedItem).idOrder);
 }