private async void SaveChangesAsync(object sender, RoutedEventArgs e) { var dialog = new MessageDialog("Are you sure?"); dialog.Title = "Really?"; dialog.Commands.Add(new UICommand { Label = "Ok", Id = 0 }); dialog.Commands.Add(new UICommand { Label = "Cancel", Id = 1 }); var res = await dialog.ShowAsync(); if ((int)res.Id == 1) { return; } if (ViewModel.SelectedDeparture == null) { ViewModel.SelectedDeparture = new Departure(); } ViewModel.SelectedDeparture.Crew = ViewModel.Crews.SingleOrDefault(c => c.ToString() == Crews.SelectedItem.ToString()); ViewModel.SelectedDeparture.Plane = ViewModel.Planes.SingleOrDefault(c => c.ToString() == Planes.SelectedItem.ToString()); ViewModel.SelectedDeparture.Flight = ViewModel.Flights.SingleOrDefault(c => c.ToString() == Flights.SelectedItem.ToString()); try { ViewModel.SelectedDeparture.Date = DateTime.Parse(Date.ToString()); } catch (Exception) { } if (ViewModel.SelectedDeparture != null) { ViewModel.UpdateDeparture(); } else { ViewModel.AddDeparture(); } }