private async void OnBuyTicket()
{
var response = await Application.Current.MainPage
.DisplayAlert("Buy", "Are you sure?",
"Yes", "No");
if (response && Function.Value.HasValue)
{
using (UserDialogs.Instance.Loading())
{
await _moviesService.BuyTicketFor(CurrentMovie.Value.Id, Function.Value.Value);
}
await _navigationService.GoToTicketPage();
}
}