private async void AddOrder_Click(object sender, RoutedEventArgs e)
        {
            await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                OrderPriorityInput.Background = new SolidColorBrush(Colors.White);
                OrderNameInput.Background     = new SolidColorBrush(Colors.White);
                ServiceInput.Background       = new SolidColorBrush(Colors.White);
            });

            if (OrderPriorityInput.SelectedIndex < 0)
            {
                await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
                {
                    OrderPriorityInput.Background = new SolidColorBrush(Colors.Red);
                });

                return;
            }
            if (ServiceInput.SelectedIndex < 0)
            {
                await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
                {
                    ServiceInput.Background = new SolidColorBrush(Colors.Red);
                });

                return;
            }
            Priority p;

            switch (OrderPriorityInput.SelectedIndex)
            {
            case 0:
                p = Priority.VeryLow;
                break;

            case 1:
                p = Priority.Low;
                break;

            case 2:
                p = Priority.Normal;
                break;

            case 3:
                p = Priority.High;
                break;

            case 4:
                p = Priority.VeryHigh;
                break;

            default:
                return;
            }
            if (OrderNameInput.Text == string.Empty || !CurrentAgency.AddOrder(new Order(OrderNameInput.Text, ServiceInput.SelectedItem as Service, p)))
            {
                await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
                {
                    OrderNameInput.Background = new SolidColorBrush(Colors.Red);
                    return;
                });
            }
            Orders.ItemsSource = CurrentAgency.Orders;

            OrderNameInput.Text = string.Empty;
            OrderPriorityInput.SelectedIndex = -1;
            ServiceInput.SelectedIndex       = -1;
        }