private void btnDrivers_Click(object sender, RoutedEventArgs e)
        {
            var driverRepository = new SqlDriverRepository(_connectionString);
            var driverWindow     = new DriverWindow(_customer, driverRepository.SelectAll());

            wndMainWindow.IsEnabled = false;
            driverWindow.ShowDialog();
            wndMainWindow.IsEnabled = true;
        }
        private void btnAdd_Click(object sender, RoutedEventArgs e)
        {
            var addDriverWindow = new AddDriverWindow(_customer);

            wndDriver.IsEnabled = false;
            addDriverWindow.ShowDialog();

            var driverRepository = new SqlDriverRepository(_connectionString);

            dgrDataDrivers.ItemsSource = driverRepository.SelectAll();

            wndDriver.IsEnabled = true;
        }
        private void btnDelete_Click(object sender, RoutedEventArgs e)
        {
            var driverRepository = new SqlDriverRepository(_connectionString);

            if (dgrDataDrivers.SelectedItem == null)
            {
                MessageBox.Show("Not selected driver.", "Selection", MessageBoxButton.OK, MessageBoxImage.Error);
                return;
            }

            Driver driver = (Driver)dgrDataDrivers.SelectedItem;

            MessageBoxResult answer = MessageBox.Show(String.Format("You really want to delete driver {0}?",
                                                                    String.Format("{0} {1}", driver.Name, driver.Surname)), "Deleting", MessageBoxButton.YesNo, MessageBoxImage.Question);

            if (answer == MessageBoxResult.Yes)
            {
                driverRepository.Delete(driver.Id);
                dgrDataDrivers.ItemsSource = driverRepository.SelectAll();
            }
        }