private void btnAdd_Click(object sender, RoutedEventArgs e)
        {
            AddCountry          countryDialog   = new AddCountry();
            AddCountryViewModel countryDialogVm = new AddCountryViewModel();

            countryDialogVm.CancelCommand = new RelayCommand(() =>
            {
                countryDialog.Close();
            });
            countryDialogVm.OKCommand = new RelayCommand(() =>
            {
                if (countryDialogVm.IsValid)
                {
                    DataProvider dp = new DataProvider();
                    City ci         = dp.AddCoutryWithCity(countryDialogVm.CountryName, countryDialogVm.CityName);
                    context.Countries.Load();
                    context.Cities.Load();
                    myCountriesViewSource.View.Refresh();
                    countryDialog.Close();
                    Messenger.Default.Send <string>(Utils.CountryAddedMessage);
                }
                else
                {
                    countryDialogVm.UserMessage = "Please Complete Info ";
                }
            });
            countryDialog.DataContext = countryDialogVm;
            countryDialog.ShowDialog();
        }