private async void getHistoryAppointment() { myAPI = RestService.For <IMyAPI>("https://goldenspa.azurewebsites.net"); var idCustomer = await myAPI.GetIdCustomer("0123456789"); string cus = idCustomer.Substring(2, idCustomer.Length - 4); var result = await myAPI.GetHistoryAppointment(cus); mAdapterAppointment = new ShoppingCardHistoryAppointment_Appointment_Customer_Adapter(result); mRecyclerViewAppointment.SetAdapter(mAdapterAppointment); }