private async void RefreshCinemas()
        {
            try
            {
                cinemasListView.IsRefreshing = true;
                var position = await GeoLocation.GetCurrentLocation();

                var cinemas = await Service.GetCinemas(position.Latitude, position.Longitude, (int)Slider.Value);

                CinemaList = new ObservableCollection <Cinema>(cinemas.Where(c => c.Name != null));
                cinemasListView.ItemsSource = CinemaList;
            }
            catch (GeolocationException E)
            {
                await DisplayAlert("Error", "Please enable the location service.", "Exit");

                AppControls.CloseApp();
            }
            catch (TaskCanceledException E)
            {
                await DisplayAlert("Oops..!!", "Unable to find your location. Please try again.", "Ok");
            }
            catch (Exception E)
            {
                await DisplayAlert("Error", $"{E} - {E.Message}", "Exit");

                AppControls.CloseApp();
            }
            finally
            {
                cinemasListView.IsRefreshing = false;
            }
        }
        private async void OnLoad()
        {
            try
            {
                showtimesListView.IsRefreshing = true;
                var showtimes = await Service.GetShowtimes(Cinema.Id, Movie.Id);

                var data = showtimes.ToArray();

                Array.Sort(data, new ShowtimeComparer());

                ShowtimesList = new ObservableCollection <Showtime>(data);

                showtimesListView.ItemsSource = ShowtimesList;
            }
            catch (Exception E)
            {
                await DisplayAlert("Error", $"{E} - {E.Message}", "Exit");

                AppControls.CloseApp();
            }
            finally
            {
                showtimesListView.IsRefreshing = false;
            }
        }
        private async void OnLoad()
        {
            try
            {
                moviesListView.IsRefreshing = true;
                var movies = await Service.GetMoviesByCinemaId(Cinema.Id);

                MovieList = new ObservableCollection <Movie>(movies.Where(m => m.Title != null));
                moviesListView.ItemsSource = MovieList;
            }
            catch (Exception E)
            {
                await DisplayAlert("Error", $"{E} - {E.Message}", "Exit");

                AppControls.CloseApp();
            }
            finally
            {
                moviesListView.IsRefreshing = false;
            }
        }