/// <summary>
/// Handles the user clicking the "Ask to lunch" button.
/// </summary>
public async void AskToLunch()
{
var location = SelectedLocation.Name == "Custom"
? new Location {
Name = CustomLocation
}
: SelectedLocation;
var lunch = new Lunch(Name,
App.User,
SelectedFriends.Concat(new[] { App.User }),
location,
SelectedDate.Add(SelectedTime).LocalDateTime);
await App.Api.PostAsync("Lunch", lunch);
ShellViewModel.Current.Navigate(typeof(Lunches));
}