private async void MapView_Tapped(object sender, Esri.ArcGISRuntime.Xamarin.Forms.GeoViewInputEventArgs e)
        {
            // Clear any existing selection.
            _damageLayer.ClearSelection();

            // Reconfigure the button.
            DeleteButton.IsEnabled = false;
            DeleteButton.Text      = "Delete feature";

            try
            {
                // Perform an identify to determine if a user tapped on a feature.
                IdentifyLayerResult identifyResult = await MyMapView.IdentifyLayerAsync(_damageLayer, e.Position, 5, false);

                // Do nothing if there are no results.
                if (!identifyResult.GeoElements.Any())
                {
                    return;
                }

                // Otherwise, get the ID of the first result.
                long featureId = (long)identifyResult.GeoElements.First().Attributes["objectid"];

                // Get the feature by constructing a query and running it.
                QueryParameters qp = new QueryParameters();
                qp.ObjectIds.Add(featureId);
                FeatureQueryResult queryResult = await _damageLayer.FeatureTable.QueryFeaturesAsync(qp);

                _tappedFeature = queryResult.First();

                // Select the feature.
                _damageLayer.SelectFeature(_tappedFeature);

                // Update the button to allow deleting the feature.
                ConfigureDeletionButton(_tappedFeature);
            }
            catch (Exception ex)
            {
                await Application.Current.MainPage.DisplayAlert("Error", ex.ToString(), "OK");
            }
        }
        private async void MapView_Tapped(object sender, GeoViewInputEventArgs e)
        {
            // Clear any existing selection.
            _damageLayer.ClearSelection();

            // Dismiss any existing callouts.
            _myMapView.DismissCallout();

            try
            {
                // Perform an identify to determine if a user tapped on a feature.
                IdentifyLayerResult identifyResult = await _myMapView.IdentifyLayerAsync(_damageLayer, e.Position, 8, false);

                // Do nothing if there are no results.
                if (!identifyResult.GeoElements.Any())
                {
                    return;
                }

                // Otherwise, get the ID of the first result.
                long featureId = (long)identifyResult.GeoElements.First().Attributes["objectid"];

                // Get the feature by constructing a query and running it.
                QueryParameters qp = new QueryParameters();
                qp.ObjectIds.Add(featureId);
                FeatureQueryResult queryResult = await _damageLayer.FeatureTable.QueryFeaturesAsync(qp);

                Feature tappedFeature = queryResult.First();

                // Select the feature.
                _damageLayer.SelectFeature(tappedFeature);

                // Show the callout.
                ShowDeletionCallout(tappedFeature);
            }
            catch (Exception ex)
            {
                ShowMessage(ex.ToString(), "There was a problem.");
            }
        }