private async void AppointmentsListView_ItemSelected(object sender, SelectedItemChangedEventArgs e) { var appointment = (AppointmentModel)e.SelectedItem; var patient = await PatientLogic.GetPatientAsync(General.UserId); var fullname = PatientLogic.GetFullName(patient.FirstName, patient.Surname); if (allAppointments.Any(a => a.PatientName == fullname && a.PatientID == patient.UserID)) { await DisplayAlert("Appointment", "You already have an appointment booked!", "Okay"); } else { var symptoms = await DisplayPromptAsync("Book Appointment", string.Format("{0}, {1}", appointment.AppointmentTime.ToLongDateString(), appointment.AppointmentTime.ToShortTimeString()), "Book", "Close", "Your symptoms ..."); if (string.IsNullOrEmpty(symptoms)) { } else { appointment.symtoms = symptoms; appointment.diagnosis = string.Empty; appointment.PatientModel = patient; appointment.PatientName = string.Format("{0} {1}", patient.FirstName, patient.Surname); appointment.PatientID = patient.UserID; await AppointmentLogic.UpdateCustomerAsync(appointment); } } }