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GeoElement Class

A marker interface implemented by objects that can be returned from an identify operation.
Inheritance Hierarchy

Namespace:  Esri.ArcGISRuntime.Data
Assembly:  Esri.ArcGISRuntime (in Esri.ArcGISRuntime.dll) Version: 100.7.0.0
Syntax
C#
public abstract class GeoElement

The GeoElement type exposes the following members.

Properties
  NameDescription
Public propertyCode exampleAttributes
Gets the attributes of this GeoElement as a collection of name/value pairs.
Public propertyCode exampleGeometry
Gets the geometry of a GeoElement.
Top
Examples

Android

Example Name: UpdateGeometries

Update a feature's location in an online feature service.

Code example screen shot.

C#
// Copyright 2019 Esri.
// 
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
// You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an 
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific 
// language governing permissions and limitations under the License.

using Android.App;
using Android.OS;
using Android.Widget;
using Esri.ArcGISRuntime.Data;
using Esri.ArcGISRuntime.Geometry;
using Esri.ArcGISRuntime.Mapping;
using Esri.ArcGISRuntime.UI.Controls;
using System;
using System.Linq;
using Android.Views;

namespace ArcGISRuntimeXamarin.Samples.UpdateGeometries
{
    [Activity (ConfigurationChanges=Android.Content.PM.ConfigChanges.Orientation | Android.Content.PM.ConfigChanges.ScreenSize)]
    [ArcGISRuntime.Samples.Shared.Attributes.Sample(
        "Update geometries (feature service)",
        "Data",
        "Update a feature's location in an online feature service.",
        "")]
    public class UpdateGeometries : Activity
    {
        // Hold a reference to the MapView.
        private MapView _myMapView;

        // URL to the feature service.
        private const string FeatureServiceUrl = "https://sampleserver6.arcgisonline.com/arcgis/rest/services/DamageAssessment/FeatureServer/0";

        // Hold a reference to the feature layer.
        private FeatureLayer _damageLayer;

        // Hold a reference to the selected feature.
        private ArcGISFeature _selectedFeature;

        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);

            Title = "Update geometries (feature service)";

            CreateLayout();
            Initialize();
        }

        private void Initialize()
        {
            // Create the map with streets basemap.
            _myMapView.Map = new Map(Basemap.CreateStreets());

            // Create the feature table, referring to the Damage Assessment feature service.
            ServiceFeatureTable damageTable = new ServiceFeatureTable(new Uri(FeatureServiceUrl));

            // Create a feature layer to visualize the features in the table.
            _damageLayer = new FeatureLayer(damageTable);

            // Add the layer to the map.
            _myMapView.Map.OperationalLayers.Add(_damageLayer);

            // Listen for user taps on the map - on tap, a feature will be selected.
            _myMapView.GeoViewTapped += MapView_Tapped;

            // Zoom to the United States.
            _myMapView.SetViewpointCenterAsync(new MapPoint(-10800000, 4500000, SpatialReferences.WebMercator), 3e7);
        }

        private void MapView_Tapped(object sender, GeoViewInputEventArgs e)
        {
            // Select the feature if none selected, move the feature otherwise.
            if (_selectedFeature == null)
            {
                // Select the feature.
                TrySelectFeature(e);
            }
            else
            {
                // Move the feature.
                MoveSelectedFeature(e);
            }
        }

        private async void MoveSelectedFeature(GeoViewInputEventArgs tapEventDetails)
        {
            try
            {
                // Get the MapPoint from the EventArgs for the tap.
                MapPoint destinationPoint = tapEventDetails.Location;

                // Normalize the point - needed when the tapped location is over the international date line.
                destinationPoint = (MapPoint) GeometryEngine.NormalizeCentralMeridian(destinationPoint);

                // Load the feature.
                await _selectedFeature.LoadAsync();

                // Update the geometry of the selected feature.
                _selectedFeature.Geometry = destinationPoint;

                // Apply the edit to the feature table.
                await _selectedFeature.FeatureTable.UpdateFeatureAsync(_selectedFeature);

                // Push the update to the service.
                ServiceFeatureTable serviceTable = (ServiceFeatureTable) _selectedFeature.FeatureTable;
                await serviceTable.ApplyEditsAsync();
                ShowMessage("Success!", $"Moved feature {_selectedFeature.Attributes["objectid"]}");
            }
            catch (Exception ex)
            {
                ShowMessage("Error when moving feature", ex.ToString());
            }
            finally
            {
                // Reset the selection.
                _damageLayer.ClearSelection();
                _selectedFeature = null;
            }
        }

        private async void TrySelectFeature(GeoViewInputEventArgs tapEventDetails)
        {
            try
            {
                // Perform an identify to determine if a user tapped on a feature.
                IdentifyLayerResult identifyResult = await _myMapView.IdentifyLayerAsync(_damageLayer, tapEventDetails.Position, 10, false);

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

                // Get the tapped feature.
                _selectedFeature = (ArcGISFeature)identifyResult.GeoElements.First();

                // Select the feature.
                _damageLayer.SelectFeature(_selectedFeature);
            }
            catch (Exception ex)
            {
                ShowMessage("Problem selecting feature", ex.ToString());
            }
        }

        private void ShowMessage(string title, string message)
        {
            // Display the message to the user.
            AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.SetMessage(message).SetTitle(title).Show();
        }

        private void CreateLayout()
        {
            // Create a new vertical layout for the app.
            var layout = new LinearLayout(this) {Orientation = Orientation.Vertical};

            // Create the help label.
            TextView helpLabel = new TextView(this);
            helpLabel.Text = "Tap to select a feature. Tap again to move it.";
            helpLabel.TextAlignment = TextAlignment.Center;
            helpLabel.Gravity = GravityFlags.Center;

            // Add the help label to the layout.
            layout.AddView(helpLabel);

            // Create the map view.
            _myMapView = new MapView(this);

            // Add the map view to the layout.
            layout.AddView(_myMapView);

            // Show the layout in the app.
            SetContentView(layout);
        }
    }
}
Examples

Xamarin Forms Android

Example Name: UpdateGeometries

Update a feature's location in an online feature service.

Code example screen shot.

C#
// Copyright 2019 Esri.
// 
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
// You may obtain a copy of the License at: http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an 
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific 
// language governing permissions and limitations under the License.

using Esri.ArcGISRuntime.Data;
using Esri.ArcGISRuntime.Geometry;
using Esri.ArcGISRuntime.Mapping;
using System;
using System.Linq;
using Xamarin.Forms;

namespace ArcGISRuntimeXamarin.Samples.UpdateGeometries
{
    [ArcGISRuntime.Samples.Shared.Attributes.Sample(
        "Update geometries (feature service)",
        "Data",
        "Update a feature's location in an online feature service.",
        "")]
    public partial class UpdateGeometries : ContentPage
    {
        // URL to the feature service.
        private const string FeatureServiceUrl = "https://sampleserver6.arcgisonline.com/arcgis/rest/services/DamageAssessment/FeatureServer/0";

        // Hold a reference to the feature layer.
        private FeatureLayer _damageLayer;

        // Hold a reference to the selected feature.
        private ArcGISFeature _selectedFeature;

        public UpdateGeometries()
        {
            InitializeComponent();
            Initialize();
        }

        private void Initialize()
        {
            // Create the map with streets basemap.
            MyMapView.Map = new Map(Basemap.CreateStreets());

            // Create the feature table, referring to the Damage Assessment feature service.
            ServiceFeatureTable damageTable = new ServiceFeatureTable(new Uri(FeatureServiceUrl));

            // Create a feature layer to visualize the features in the table.
            _damageLayer = new FeatureLayer(damageTable);

            // Add the layer to the map.
            MyMapView.Map.OperationalLayers.Add(_damageLayer);

            // Listen for user taps on the map - on tap, a feature will be selected.
            MyMapView.GeoViewTapped += MapView_Tapped;

            // Zoom to the United States.
            MyMapView.SetViewpointCenterAsync(new MapPoint(-10800000, 4500000, SpatialReferences.WebMercator), 3e7);
        }

        private void MapView_Tapped(object sender, Esri.ArcGISRuntime.Xamarin.Forms.GeoViewInputEventArgs e)
        {
            // Select the feature if none selected, move the feature otherwise.
            if (_selectedFeature == null)
            {
                // Select the feature.
                TrySelectFeature(e);
            }
            else
            {
                // Move the feature.
                MoveSelectedFeature(e);
            }
        }

        private async void MoveSelectedFeature(Esri.ArcGISRuntime.Xamarin.Forms.GeoViewInputEventArgs tapEventDetails)
        {
            try
            {
                // Get the MapPoint from the EventArgs for the tap.
                MapPoint destinationPoint = tapEventDetails.Location;

                // Normalize the point - needed when the tapped location is over the international date line.
                destinationPoint = (MapPoint) GeometryEngine.NormalizeCentralMeridian(destinationPoint);

                // Load the feature.
                await _selectedFeature.LoadAsync();

                // Update the geometry of the selected feature.
                _selectedFeature.Geometry = destinationPoint;

                // Apply the edit to the feature table.
                await _selectedFeature.FeatureTable.UpdateFeatureAsync(_selectedFeature);

                // Push the update to the service.
                ServiceFeatureTable serviceTable = (ServiceFeatureTable) _selectedFeature.FeatureTable;
                await serviceTable.ApplyEditsAsync();
                await Application.Current.MainPage.DisplayAlert("Success!", $"Moved feature {_selectedFeature.Attributes["objectid"]}", "OK");
            }
            catch (Exception ex)
            {
                await Application.Current.MainPage.DisplayAlert("Error when moving feature", ex.ToString(), "OK");
            }
            finally
            {
                // Reset the selection.
                _damageLayer.ClearSelection();
                _selectedFeature = null;
            }
        }

        private async void TrySelectFeature(Esri.ArcGISRuntime.Xamarin.Forms.GeoViewInputEventArgs tapEventDetails)
        {
            try
            {
                // Perform an identify to determine if a user tapped on a feature.
                IdentifyLayerResult identifyResult = await MyMapView.IdentifyLayerAsync(_damageLayer, tapEventDetails.Position, 10, false);

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

                // Get the tapped feature.
                _selectedFeature = (ArcGISFeature)identifyResult.GeoElements.First();

                // Select the feature.
                _damageLayer.SelectFeature(_selectedFeature);
            }
            catch (Exception ex)
            {
                await Application.Current.MainPage.DisplayAlert("Problem selecting feature", ex.ToString(), "OK");
            }
        }
    }
}
XAML
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"             
             xmlns:esriUI="clr-namespace:Esri.ArcGISRuntime.Xamarin.Forms;assembly=Esri.ArcGISRuntime.Xamarin.Forms"
             xmlns:resources="clr-namespace:Forms.Resources;assembly=ArcGISRuntime"
             x:Class="ArcGISRuntimeXamarin.Samples.UpdateGeometries.UpdateGeometries">
    <RelativeLayout>
        <esriUI:MapView x:Name="MyMapView" Style="{StaticResource MapWithFormStyle}"
                        BindingContext="{x:Reference Name=ResponsiveFormContainer}" />
        <resources:ResponsiveFormContainer x:Name="ResponsiveFormContainer">
            <StackLayout>
                <Label Text="Tap to select a feature. Tap again to move it."
                       HorizontalTextAlignment="Center"/>
            </StackLayout>
        </resources:ResponsiveFormContainer>
    </RelativeLayout>
</ContentPage>
See Also
Additional Examples
Hyperlink to ExampleDescription
Animate3DGraphicAn `OrbitGeoElementCameraController` follows a graphic while the graphic's position and rotation are animated.
ChooseCameraControllerControl the behavior of the camera in a scene.
DeleteFeaturesDelete features from an online feature service.
EditFeatureAttachmentsAdd, delete, and download attachments for features from a service.
IdentifyKmlFeaturesThis sample demonstrates how to identify features in a KML layer. Identified feature attributes are displayed in a callout to simulate a popup.
IdentifyLayersIdentify features in all layers in a map. MapView supports identifying features across multiple layers. Because some layer types have sublayers, the sample recursively counts results for sublayers within each layer.
LineOfSightGeoElementShow a line of sight between two moving objects.
ListRelatedFeaturesList features related to the selected feature.
OfflineGeocodeGeocode addresses to locations and reverse geocode locations to addresses offline.
ReverseGeocodeUse an online service to find the address for a tapped point.
SceneLayerSelectionIdentify GeoElements in a scene layer.
SelectEncFeaturesSelect features in an ENC layer.
TraceUtilityNetworkDiscover connected features in a utility network using connected, subnetwork, upstream, and downstream traces.
UpdateAttributesUpdate feature attributes in an online feature service.
UpdateGeometriesUpdate a feature's location in an online feature service.
UseDistanceCompositeSymChange a graphic's symbol based on the camera's proximity to it.
ViewshedGeoElementAnalyze the viewshed for an object (GeoElement) in a scene.
WmsIdentifyIdentify features in a WMS layer and display the associated popup content.