private void AddCityButton_Click(object sender, RoutedEventArgs e)
        {
            AddCity addCityWin = new AddCity();

            addCityWin.Closed += addCityWin_Closed;
            addCityWin.ShowDialog();
        }
        private void EditCityButton_Click(object sender, RoutedEventArgs e)
        {
            if (CityDataGrid.SelectedItems.Count != 1)
            {
                MessageBox.Show("Select 1 city to edit");
                return;
            }
            AddCity addCityWin = new AddCity(((City)CityDataGrid.SelectedItem).CITY_CODE);

            addCityWin.Closed += addCityWin_Closed;
            addCityWin.ShowDialog();
        }