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PortalItemGetDataAsync Method (CancellationToken, String)

Gets the item data. The data component of an item (the "item file") is used to stream the actual data represented by the item to the client. This resource is available only for the file and text item types.

Namespace:  Esri.ArcGISRuntime.Portal
Assembly:  Esri.ArcGISRuntime (in Esri.ArcGISRuntime.dll) Version: 100.8.0.0
Syntax
C#
public Task<Stream> GetDataAsync(
	CancellationToken cancellationToken,
	string outputFormat = null
)

Parameters

cancellationToken
Type: System.ThreadingCancellationToken
A CancellationToken with which to cancel the operation if required.
outputFormat (Optional)
Type: SystemString
An optional output format parameter. Only applies to Package types. 'zip' will download a package in zip format rather than the package format.

Return Value

Type: TaskStream
The task object representing the asynchronous get item data operation. The value of the task result is a Stream object.
Examples

Android

Example Name: FeatureLayerDefinitionExpression

Limit the features displayed on a map with a definition expression.

Code example screen shot.

C#
// Copyright 2016 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;

namespace ArcGISRuntime.Samples.FeatureLayerDefinitionExpression
{
    [Activity (ConfigurationChanges=Android.Content.PM.ConfigChanges.Orientation | Android.Content.PM.ConfigChanges.ScreenSize)]
    [ArcGISRuntime.Samples.Shared.Attributes.Sample(
        "Feature layer definition expression",
        "Layers",
        "This sample demonstrates how to apply definition expression to a feature layer for filtering features. It also shows how to reset the definition expression.",
        "")]
    public class FeatureLayerDefinitionExpression : Activity
    {
        // Hold a reference to the map view
        private MapView _myMapView;

        // Create and hold reference to the feature layer
        private FeatureLayer _featureLayer;

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

            Title = "Feature layer definition expression";

            // Create the UI, setup the control references and execute initialization 
            CreateLayout();
            Initialize();
        }

        private void Initialize()
        {
            // Create new Map with basemap
            Map myMap = new Map(Basemap.CreateTopographic());

            // Create a mappoint the map should zoom to
            MapPoint mapPoint = new MapPoint(-13630484, 4545415, SpatialReferences.WebMercator);

            // Set the initial viewpoint for map
            myMap.InitialViewpoint = new Viewpoint(mapPoint, 90000);

            // Provide used Map to the MapView
            _myMapView.Map = myMap;

            // Create the uri for the feature service
            Uri featureServiceUri = new Uri("https://sampleserver6.arcgisonline.com/arcgis/rest/services/SF311/FeatureServer/0");

            // Initialize feature table using a url to feature server url
            ServiceFeatureTable featureTable = new ServiceFeatureTable(featureServiceUri);

            // Initialize a new feature layer based on the feature table
            _featureLayer = new FeatureLayer(featureTable);

            //Add the feature layer to the map
            myMap.OperationalLayers.Add(_featureLayer);
        }

        private void OnApplyExpressionClicked(object sender, EventArgs e)
        {
            // Adding definition expression to show specific features only
            _featureLayer.DefinitionExpression = "req_Type = 'Tree Maintenance or Damage'";
        }

        private void OnResetButtonClicked(object sender, EventArgs e)
        {
            // Reset the definition expression to see all features again
            _featureLayer.DefinitionExpression = "";
        }

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

            // Create a button to reset the renderer
            Button resetButton = new Button(this)
            {
                Text = "Reset"
            };
            resetButton.Click += OnResetButtonClicked;

            // Create a button to apply new renderer
            Button overrideButton = new Button(this)
            {
                Text = "Apply expression"
            };
            overrideButton.Click += OnApplyExpressionClicked;

            // Add Reset Button to the layout
            layout.AddView(resetButton);

            // Add Override Button to the layout
            layout.AddView(overrideButton);

            // Add the map view to the layout
            _myMapView = new MapView(this);
            layout.AddView(_myMapView);

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

Xamarin Forms Android

Example Name: FeatureLayerDefinitionExpression

Limit the features displayed on a map with a definition expression.

Code example screen shot.

C#
// Copyright 2016 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 Xamarin.Forms;

namespace ArcGISRuntime.Samples.FeatureLayerDefinitionExpression
{
    [ArcGISRuntime.Samples.Shared.Attributes.Sample(
        "Feature layer definition expression",
        "Layers",
        "This sample demonstrates how to apply definition expression to a feature layer for filtering features. It also shows how to reset the definition expression.",
        "")]
    public partial class FeatureLayerDefinitionExpression : ContentPage
    {
        //Create and hold reference to the feature layer
        private FeatureLayer _featureLayer;

        public FeatureLayerDefinitionExpression()
        {
            InitializeComponent ();

            //setup the control references and execute initialization 
            Initialize();
        }

        private void Initialize()
        {
            // Create new Map with basemap
            Map myMap = new Map(Basemap.CreateTopographic());

            // Create a MapPoint the map should zoom to
            MapPoint mapPoint = new MapPoint(
                -13630484, 4545415, SpatialReferences.WebMercator);

            // Set the initial viewpoint for map
            myMap.InitialViewpoint = new Viewpoint(mapPoint, 90000);

            // Provide used Map to the MapView
            MyMapView.Map = myMap;

            // Create the uri for the feature service
            Uri featureServiceUri = new Uri(
                "https://sampleserver6.arcgisonline.com/arcgis/rest/services/SF311/FeatureServer/0");

            // Initialize feature table using a url to feature server url
            ServiceFeatureTable featureTable = new ServiceFeatureTable(featureServiceUri);

            // Initialize a new feature layer based on the feature table
            _featureLayer = new FeatureLayer(featureTable);

            //Add the feature layer to the map
            myMap.OperationalLayers.Add(_featureLayer);
        }

        private void OnApplyExpressionClicked(object sender, EventArgs e)
        {
            // Adding definition expression to show specific features only
            _featureLayer.DefinitionExpression = "req_Type = 'Tree Maintenance or Damage'";
        }

        private void OnResetButtonClicked(object sender, EventArgs e)
        {
            // Reset the definition expression to see all features again
            _featureLayer.DefinitionExpression = "";
        }
    }
}
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"
             x:Class="ArcGISRuntime.Samples.FeatureLayerDefinitionExpression.FeatureLayerDefinitionExpression">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="auto" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*" />
            <ColumnDefinition Width="*" />
        </Grid.ColumnDefinitions>
        <Button Clicked="OnApplyExpressionClicked" Text="Apply Expression" Grid.Row="0" Grid.Column="0" />
        <Button Clicked="OnResetButtonClicked" Text="Reset" Grid.Row="0" Grid.Column="1" />
        <esriUI:MapView x:Name="MyMapView" Grid.Row="1" Grid.ColumnSpan="2" />
    </Grid>
</ContentPage>
See Also
Additional Examples
Hyperlink to ExampleDescription
AccessLoadStatusDetermine the map's load status which can be: `NotLoaded`, `FailedToLoad`, `Loading`, `Loaded`.
AddAnIntegratedMeshLayerView an integrated mesh layer from a scene service.
AddEncExchangeSetDisplay nautical charts per the ENC specification.
AddFeaturesAdd features to a feature layer.
AddGraphicsRendererA renderer allows you to change the style of all graphics in a graphics overlay by referencing a single symbol style.
AddGraphicsWithSymbolsUse a symbol style to display a graphic on a graphics overlay.
AddPointSceneLayerView a point scene layer from a scene service.
AnalyzeHotspotsUse a geoprocessing service and a set of features to identify statistically significant hot spots and cold spots.
AnalyzeViewshedCalculate a viewshed using a geoprocessing service, in this case showing what parts of a landscape are visible from points on mountainous terrain.
Animate3DGraphicAn `OrbitGeoElementCameraController` follows a graphic while the graphic's position and rotation are animated.
ApplyScheduledUpdatesApply scheduled updates to a downloaded preplanned map area.
ArcGISMapImageLayerUrlAdd an ArcGIS Map Image Layer from a URL to a map.
ArcGISTiledLayerUrlLoad an ArcGIS tiled layer from a URL.
ArcGISVectorTiledLayerUrlLoad an ArcGIS Vector Tiled Layer from a URL.
AuthorMapCreate and save a map as an ArcGIS `PortalItem` (i.e. web map).
BrowseWfsLayersBrowse a WFS service for layers and add them to the map.
BufferCreate a buffer around a map point and display the results as a `Graphic`
BufferListGenerate multiple individual buffers or a single unioned buffer around multiple points.
ChangeAtmosphereEffectChanges the appearance of the atmosphere in a scene.
ChangeBasemapChange a map's basemap. A basemap is beneath all layers on a `Map` and is used to provide visual reference for the operational layers.
ChangeBlendRendererBlend a hillshade with a raster by specifying the elevation data. The resulting raster looks similar to the original raster, but with some terrain shading, giving it a textured look.
ChangeEncDisplaySettingsConfigure the display of ENC content.
ChangeFeatureLayerRendererChange the appearance of a feature layer with a renderer.
ChangeStretchRendererUse a stretch renderer to enhance the visual contrast of raster data for analysis.
ChangeSublayerRendererApply a renderer to a sublayer.
ChangeSublayerVisibilityChange the visibility of sublayers.
ChangeTimeExtentFilter data in layers by applying a time extent to a MapView.
ChangeViewpointSet the map view to a new viewpoint.
ChooseCameraControllerControl the behavior of the camera in a scene.
ClipGeometryClip a geometry with another geometry.
ClosestFacilityFind a route to the closest facility from a location.
ClosestFacilityStaticFind routes from several locations to the respective closest facility.
ConfigureSubnetworkTraceGet a server-defined trace configuration for a given tier and modify its traversability scope, add new condition barriers and control what is included in the subnetwork trace result.
ControlAnnotationSublayerVisibilityUse annotation sublayers to gain finer control of annotation layer subtypes.
ConvexHullCreate a convex hull for a given set of points. The convex hull is a polygon with shortest perimeter that encloses a set of points. As a visual analogy, consider a set of points as nails in a board. The convex hull of the points would be like a rubber band stretched around the outermost nails.
ConvexHullListGenerate convex hull polygon(s) from multiple input geometries.
CreateAndSaveKmlFileConstruct a KML document and save it as a KMZ file.
CreateFeatureCollectionLayerCreate a Feature Collection Layer from a Feature Collection Table, and add it to a map.
CreateGeometriesCreate simple geometry types.
CreateTerrainSurfaceFromRasterSet the terrain surface with elevation described by a raster file.
CreateTerrainSurfaceFromTilePackageSet the terrain surface with elevation described by a local tile package.
CustomDictionaryStyleUse a custom dictionary style (.stylx) to symbolize features using a variety of attribute values.
CutGeometryCut a geometry along a polyline.
DeleteFeaturesDelete features from an online feature service.
DensifyAndGeneralizeA multipart geometry can be densified by adding interpolated points at regular intervals. Generalizing multipart geometry simplifies it while preserving its general shape. Densifying a multipart geometry adds more vertices at regular intervals.
DictionaryRendererGraphicsOverlayThis sample demonstrates applying a dictionary renderer to graphics, in order to display military symbology without the need for a feature table.
DisplayAnnotationDisplay annotation from a feature service URL.
DisplayDeviceLocationDisplay your current position on the map, as well as switch between different types of auto pan Modes.
DisplayDrawingStatusGet the draw status of your map view or scene view to know when all layers in the map or scene have finished drawing.
DisplayGridDisplay coordinate system grids including Latitude/Longitude, MGRS, UTM and USNG on a map view. Also, toggle label visibility and change the color of grid lines and grid labels.
DisplayKmlDisplay KML from a URL, portal item, or local KML file.
DisplayKmlNetworkLinksDisplay a file with a KML network link, including displaying any network link control messages at launch.
DisplayLayerViewStateDetermine if a layer is currently being viewed.
DisplayMapDisplay a map with an imagery basemap.
DisplaySceneDisplay a scene with a terrain surface and some imagery.
DisplaySubtypeFeatureLayerDisplays a composite layer of all the subtype values in a feature class.
DisplayUtilityAssociationsCreate graphics for utility associations in a utility network.
DisplayWfsDisplay a layer from a WFS service, requesting only features for the current extent.
DistanceMeasurementMeasure distances between two points in 3D.
DownloadPreplannedMapTake a map offline using a preplanned map area.
EditAndSyncFeaturesSynchronize offline edits with a feature service.
EditFeatureAttachmentsAdd, delete, and download attachments for features from a service.
EditKmlGroundOverlayEdit the values of a KML ground overlay.
ExportTilesDownload tiles to a local tile cache file stored on the device.
FeatureCollectionLayerFromPortalCreate a feature collection layer from a portal item.
FeatureCollectionLayerFromQueryCreate a feature collection layer to show a query result from a service feature table.
FeatureLayerDefinitionExpressionLimit the features displayed on a map with a definition expression.
FeatureLayerDictionaryRendererConvert features into graphics to show them with mil2525d symbols.
FeatureLayerExtrusionExtrude features based on their attributes.
FeatureLayerGeodatabaseDisplay features from a local geodatabase.
FeatureLayerGeoPackageDisplay features from a local GeoPackage.
FeatureLayerQueryFind features in a feature table which match an SQL query.
FeatureLayerRenderingModeMapRender features statically or dynamically by setting the feature layer rendering mode.
FeatureLayerRenderingModeSceneRender features in a scene statically or dynamically by setting the feature layer rendering mode.
FeatureLayerSelectionSelect features in a feature layer.
FeatureLayerShapefileOpen a shapefile stored on the device and display it as a feature layer with default symbology.
FeatureLayerTimeOffsetDisplay a time-enabled feature layer with a time offset.
FeatureLayerUrlShow features from an online feature service.
FindAddressFind the location for an address.
FindPlaceFind places of interest near a location or within a specific area.
FindRouteDisplay directions for a route between two points.
FindServiceAreaFind the service area within a network from a given point.
FindServiceAreasForMultipleFacilitiesFind the service areas of several facilities from a feature service.
FormatCoordinatesFormat coordinates in a variety of common notations.
GenerateGeodatabaseGenerate a local geodatabase from an online feature service.
GenerateOfflineMapTake a web map offline.
GenerateOfflineMapWithOverridesTake a web map offline with additional options for each layer.
GeodatabaseTransactionsUse transactions to manage how changes are committed to a geodatabase.
GeodesicOperationsCalculate a geodesic path between two points and measure its distance.
GeoViewSyncKeep the view points of two views (e.g. MapView and SceneView) synchronized with each other.
GetElevationAtPointGet the elevation for a given point on a surface in a scene.
GroupLayersGroup a collection of layers together and toggle their visibility as a group.
HonorMobileMapPackageExpirationAccess the expiration information of an expired mobile map package.
IdentifyGraphicsDisplay an alert message when a graphic is clicked.
IdentifyKmlFeaturesShow a callout with formatted content for a KML feature.
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.
IntegratedWindowsAuthConnect to an IWA secured Portal and search for maps.
LineOfSightGeoElementShow a line of sight between two moving objects.
LineOfSightLocationPerform a line of sight analysis between two points in real time.
ListGeodatabaseVersionsConnect to a service and list versions of the geodatabase.
ListKmlContentsList the contents of a KML file.
ListRelatedFeaturesList features related to the selected feature.
ListTransformationsGet a list of suitable transformations for projecting a geometry between two spatial references with different horizontal datums.
LoadWebTiledLayerDisplay a tiled web layer.
ManageBookmarksAccess and create bookmarks on a map.
ManageOperationalLayersAdd, remove, and reorder operational layers in a map.
MapImageLayerTablesFind features in a spatial table related to features in a non-spatial table.
MapImageSublayerQueryFind features in a sublayer based on attributes and location.
MapReferenceScaleSet the map's reference scale and which feature layers should honor the reference scale.
MapRotationRotate a map.
MobileMapSearchAndRouteDisplay maps and use locators to enable search and routing offline using a Mobile Map Package.
NavigateRouteUse a routing service to navigate between points.
NavigateRouteReroutingNavigate between two points and dynamically recalculate an alternate route when the original route is unavailable.
NearestVertexFind the closest vertex and coordinate of a geometry to a point.
OAuthThis sample demonstrates how to authenticate with ArcGIS Online (or your own portal) using OAuth2 to access secured resources (such as private web maps or layers). Accessing secured items requires a login on the portal that hosts them (an ArcGIS Online account, for example).
OfflineBasemapByReferenceUse the `OfflineMapTask` to take a web map offline, but instead of downloading an online basemap, use one which is already on the device.
OfflineGeocodeGeocode addresses to locations and reverse geocode locations to addresses offline.
OfflineRoutingSolve a route on-the-fly using offline data.
OpenMapURLDisplay a web map.
OpenMobileMapDisplay a map from a mobile map package.
OpenMobileScenePackageOpens and displays a scene from a Mobile Scene Package (.mspk).
OpenSceneOpen a web scene from a portal item.
OpenStreetMapLayerAdd OpenStreetMap as a basemap layer.
PerformValveIsolationTraceRun a filtered trace to locate operable features that will isolate an area from the flow of network resources.
PlayKmlToursPlay tours in KML files.
ProjectProject a point from one spatial reference to another.
ProjectWithSpecificTransformationProject a point from one coordinate system to another using a specific transformation step.
QueryFeatureCountAndExtentZoom to features matching a query and count the features in the current visible extent.
RasterColormapRendererApply a colormap renderer to a raster.
RasterHillshadeUse a hillshade renderer on a raster.
RasterLayerFileCreate and use a raster layer made from a local raster file.
RasterLayerGeoPackageDisplay a raster contained in a GeoPackage.
RasterLayerImageServiceRasterCreate a raster layer from a raster image service.
RasterLayerRasterFunctionLoad a raster from a service, then apply a function to it.
RasterRenderingRuleDisplay a raster on a map and apply different rendering rules to that raster.
RasterRgbRendererApply an RGB renderer to a raster layer to enhance feature visibility.
ReadGeoPackageAdd rasters and feature tables from a GeoPackage to a map.
ReadShapefileMetadataRead a shapefile and display its metadata.
RenderPictureMarkersUse pictures for markers.
RenderSimpleMarkersShow a simple marker symbol on a map.
RenderUniqueValuesRender features in a layer using a distinct symbol for each unique attribute value.
ReverseGeocodeUse an online service to find the address for a tapped point.
RouteAroundBarriersFind a route that reaches all stops without crossing any barriers.
SceneLayerSelectionIdentify features in a scene to select.
SceneLayerUrlDisplay an ArcGIS scene layer from a URL.
ScenePropertiesExpressionsUpdate the orientation of a graphic using expressions based on its attributes.
SceneSymbolsShow various kinds of 3D symbols in a scene.
SearchPortalMapsFind webmap portal items by using a search term.
SelectEncFeaturesSelect features in an ENC layer.
ServiceFeatureTableCacheDisplay a feature layer from a service using the **on interaction cache** feature request mode.
ServiceFeatureTableManualCacheDisplay a feature layer from a service using the **manual cache** feature request mode.
ServiceFeatureTableNoCacheDisplay a feature layer from a service using the **no cache** feature request mode.
SetInitialMapAreaDisplay the map at an initial viewpoint representing a bounding geometry.
SetInitialMapLocationDisplay a basemap centered at an initial location and scale.
SetMapSpatialReferenceSpecify a map's spatial reference.
SetMinMaxScaleRestrict zooming between specific scale ranges.
ShowCalloutShow a callout with the latitude and longitude of user-tapped points.
ShowLabelsOnLayerDisplay custom labels on a feature layer.
ShowLocationHistoryDisplay your location history on the map.
ShowMagnifierTap and hold on a map to show a magnifier.
SimpleRenderersDisplay common symbols for all graphics in a graphics overlay with a renderer.
SketchOnMapUse the Sketch Editor to edit or sketch a new point, line, or polygon geometry on to a map.
SpatialOperationsFind the union, intersection, or difference of two geometries.
SpatialRelationshipsDetermine spatial relationships between two geometries.
StatisticalQueryQuery a table to get aggregated statistics back for a specific field.
StatsQueryGroupAndSortQuery a feature table for statistics, grouping and sorting by different fields.
StyleWmsLayerChange the style of a Web Map Service (WMS) layer.
SurfacePlacementsPosition graphics relative to a surface using different surface placement modes.
SymbolizeShapefileDisplay a shapefile with custom symbology.
SymbolsFromMobileStyleCombine multiple symbols from a mobile style file into a single symbol.
TakeScreenshotTake a screenshot of the map.
TerrainExaggerationVertically exaggerate terrain in a scene.
TimeBasedQueryQuery data using a time extent.
TokenSecuredChallengeThis sample demonstrates how to prompt the user for a username and password to authenticate with ArcGIS Server to access an ArcGIS token-secured service. Accessing secured services requires a login that's been defined on the server.
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.
ViewContentBeneathSurfaceSee through terrain in a scene and move the camera underground.
ViewPointCloudDataOfflineDisplay local 3D point cloud data.
ViewshedCameraAnalyze the viewshed for a camera. A viewshed shows the visible and obstructed areas from an observer's vantage point.
ViewshedGeoElementAnalyze the viewshed for an object (GeoElement) in a scene.
ViewshedLocationPerform a viewshed analysis from a defined vantage point.
WfsXmlQueryLoad a WFS feature table using an XML query.
WmsIdentifyIdentify features in a WMS layer and display the associated popup content.
WMSLayerUrlDisplay a WMS layer using a WMS service URL.
WmsServiceCatalogConnect to a WMS service and show the available layers and sublayers.
WMTSLayerDisplay a layer from a Web Map Tile Service.