OGCFeatureLayerView

Property Overview

Property Details

availableFields String[]readonly

A list of attribute fields fetched for each feature including fields required for layer's renderer labelingInfo, elevationInfo, and additional fields defined on the outFields properties. The availableFields property is populated when the layerView has finished updating. The availableFields is used when filtering or querying features on the client-side.

Example

const layerView = await view.whenLayerView(layer);

// availableFields will become available once the
// layerView finishes updating
await reactiveUtils.whenOnce(() => !layerView.updating);

try {
  const results = await layerView.queryFeatures({
    outFields: layerView.availableFields,
    where: "DEW_POINT > 10"
  });
  console.log(results.features.length, " features returned");
} catch(error) {
  console.log("query failed: ", error);
}

dataUpdating Booleanreadonly

Since: ArcGIS Maps SDK for JavaScript 4.28

Indicates if the layer view is updating its data and new features are being fetched. It becomes false when layer queries finish executing. Watch this property along with updating property to know when to re-execute client-side queries after an update cycle. For example, a query that returns the number of features available in the layer view should be executed when dataUpdating becomes false. The dataUpdating property can only be true when updating is also true.

Known Limitations

• The dataUpdating is only supported in 2D MapView.

Example

// watch layer view updating and dataUpdating to get the count of features
// available in layer view. Only execute the query once new features are fetched.
let dataWasUpdated = lv.dataUpdating;
reactiveUtils.watch(() => [lv.updating, lv.dataUpdating],
  ([updating, dataUpdating]) => {
  dataWasUpdated ||= dataUpdating;
  if (!updating && dataWasUpdated) {
   dataWasUpdated = false;
   lv.queryFeatureCount().then((results)=>{
      console.log("number of features in layerView", results);
    });
  }
});

declaredClass Stringreadonly inherited

The name of the class. The declared class name is formatted as esri.folder.className.

featureEffect FeatureEffectautocast

Since: ArcGIS Maps SDK for JavaScript 4.22

The featureEffect can be used to draw attention features of interest. It allows for the selection of features via a filter, and an includedEffect and excludedEffect are applied to those features that respectively pass or fail the filter requirements.

If the featureEffect is set on the layer, it will be inherited by layerView.featureEffect unless the developer overrides it on the layerView. The layerView.featureEffect will take precedence over layer.featureEffect if both properties are set.

Known Limitations

• FeatureEffect is not supported in the following scenarios:
  • In 3D SceneViews
  • In a layer rendered with a HeatmapRenderer
  • When FeatureReductionCluster is enabled
  • When a map is printed
• A FeatureEffect set on a layerView cannot persisted in a WebMap.

See also

• FeatureLayer.featureEffect

• Sample - Apply effects to features

• Sample - Apply drop-shadow effect to a layerView

Examples

// gray out features that fall outside of the 3 mile buffer of the mouse's location
// by setting feature effect on excluded features
layerView.featureEffect = new FeatureEffect({
  filter: new FeatureFilter({
    geometry: filterGeometry,
    spatialRelationship: "intersects",
    distance: 3,
    units: "miles"
  }),
  excludedEffect: "grayscale(100%) opacity(30%)"
});

// Apply a drop-shadow feature effect to the features that intersect the borough boundaries,
// while applying blur and brightness effects to the features that are excluded from filter criteria.
// The resulting map will make it easier to spot if the residents are more likely to experience deprivation
// if they live on a borough boundary.
const featureFilter = new FeatureFilter({
  where: "BoroughEdge='true'"
});
layerView.featureEffect = new FeatureEffect({
  filter: featureFilter,
  includedEffect: "drop-shadow(3px, 3px, 3px, black)",
  excludedEffect: "blur(1px) brightness(65%)"
});

filter FeatureFilterautocast

The attribute, geometry, and time extent filter. Only the features that satisfy the filter are displayed on the view.

See also

• Sample - Filter features by attributes

• Sample - Filter features by geometry

• availableFields

Example

// display rain gauges where their water percent is over 30%
// and if the gauges are completely contained by the 10-mile
// buffer around the filter geometry
featureLayerView.filter = new FeatureFilter({
  where: "percentile >= 30",
  geometry: filterPolygon,
  spatialRelationship: "contains",
  distance: 10,
  units: "miles"
});

highlightOptions HighlightOptions

Since: ArcGIS Maps SDK for JavaScript 4.26

Options for configuring the highlight. Use the highlight() method on the layer view to highlight a feature. The layerView's highlightOptions will take precedence over the view's highlightOptions if both properties are set.

Known Limitations

• The highlightOptions on layer views are only supported in 2D MapView.

See also

• highlight()

• Sample: Highlight SceneLayer

• Sample: Highlight point features

Example

// Features in the layerview will be highlighted with bright
// yellow colors in the map.
const layerView = await view.whenLayerView(layer);
layerView.highlightOptions = {
  color: [255, 255, 0, 1],
  haloOpacity: 0.9,
  fillOpacity: 0.2
};

layer Layerreadonly inherited

The layer being viewed.

maximumNumberOfFeatures Number

The maximum number of features that can be displayed at a time. This setting currently only applies to SceneView. By default, the maximum number of features is estimated automatically depending on the symbology, geometry complexity, memory consumption and display quality profile.

Changing this setting to a higher value may lead to a significant decrease in performance and increase in memory usage.

Known Limitations

The maximumNumberOfFeatures is only supported in 3D SceneViews.

maximumNumberOfFeaturesExceeded Boolean

Signifies whether the maximum number of features has been exceeded. Not all features could be displayed when this value is true. This setting currently only applies to SceneView.

Known Limitations

The maximumNumberOfFeaturesExceeded is only supported in 3D SceneViews.

spatialReferenceSupported Booleanreadonly inherited

Since: ArcGIS Maps SDK for JavaScript 4.23

Indicates if the spatialReference of the MapView is supported by the layer view. When false layer view will be suspended.

See also

• suspended

suspended Booleanreadonly inherited

Value is true if the layer is suspended (i.e., layer will not redraw or update itself when the extent changes).

See also

• spatialReferenceSupported

updating Booleanreadonly inherited

Indicates if the layer view is making any updates that will impact what is displayed on the map. For example, this value is true when renderer, definitionExpression, filter or effect is changed or if the layer view is in the process of the fetching data.

Watch dataUpdating property instead to only know when the data has been updated (e.g. to run statistics query on all feature available in the layer view).

Default Value:false

Example

// Check for the first time layerView.updating becomes false. Then query for
// features that are visible within the view associated with the layer view.
await reactiveUtils.whenOnce(() => !layerView.updating);
const query = layerView.createQuery();
query.geometry = layerView.view.extent;
const result = layerView.queryFeatures(query);

view MapView|SceneViewreadonly inherited

Since: ArcGIS Maps SDK for JavaScript 4.28

A reference to the MapView or SceneView associated with the layer view.

Example

// Check for the first time layerView.updating becomes false. Then query for
// features that are visible within the view associated with the layer view.
await reactiveUtils.whenOnce(() => !layerView.updating);
const query = layerView.createQuery();
query.geometry = layerView.view.extent;
const result = layerView.queryFeatures(query);

visible Boolean inherited

When true, the layer is visible in the view. Value of this property is inherited from the layer.visible unless the developer overrides it. The layerView.visible will take precedence over layer.visible if both properties are set.

Default Value:true

Method Overview

Method Details

addHandles(handleOrHandles, groupKey)inherited

Since: ArcGIS Maps SDK for JavaScript 4.25

Adds one or more handles which are to be tied to the lifecycle of the object. The handles will be removed when the object is destroyed.

// Manually manage handles
const handle = reactiveUtils.when(
  () => !view.updating,
  () => {
    wkidSelect.disabled = false;
  },
  { once: true }
);

this.addHandles(handle);

// Destroy the object
this.destroy();

Parameters

handleOrHandles WatchHandle|WatchHandle[] Handles marked for removal once the object is destroyed.

groupKey * optional Key identifying the group to which the handles should be added. All the handles in the group can later be removed with Accessor.removeHandles(). If no key is provided the handles are added to a default group.

createAggregateQuery(){Query}

Since: ArcGIS Maps SDK for JavaScript 4.25

Creates query parameter object that can be used to fetch aggregate features as they are being displayed. It sets the query parameter's outFields property to ["*"] and returnGeometry to true. The output spatial reference outSpatialReference is set to the spatial reference of the view.

Returns

Type	Description
Query	The query parameter object.

See also

• queryAggregates

createQuery(){Query}

Creates a query parameter object that can be used to fetch features as they are being displayed. It sets the query parameter's outFields property to ["*"] and returnGeometry to true. The outSpatialReference is set to the spatial reference of the view. Parameters of the filter currently applied to the layer view are also incorporated in the returned query object. The results will include geometries of features and values for all fields.

Returns

Type	Description
Query	The query object

Example

const query = csvLayerView.createQuery();
query.where = "magnitude > 4";
csvLayerView.queryFeatures(query).then(function(results) {
  console.log(results);
})
.catch(function(error) {
  console.log(error);
});

hasHandles(groupKey){Boolean}inherited

Since: ArcGIS Maps SDK for JavaScript 4.25

Returns true if a named group of handles exist.

Parameter

groupKey * optional A group key.

Returns

Type	Description
Boolean	Returns true if a named group of handles exist.

Example

// Remove a named group of handles if they exist.
if (obj.hasHandles("watch-view-updates")) {
  obj.removeHandles("watch-view-updates");
}

highlight(target){Handle}

Highlights the given feature(s) in a layer view. The layerView's highlightOptions will take precedence over the view's highlightOptions if both properties are set.

Release specific changes:

• At version 4.23, the highlight() method was added to ImageryLayerView.

Parameter

target Graphic|Graphic[]|Number|Number[] optional The feature(s) to highlight. When passing a graphic or array of graphics, each feature must have a valid objectID. You may alternatively pass one or more objectIDs as a single number or an array.

Returns

Type	Description
Handle	Returns a highlight handler with a remove() method that can be called to remove the highlight.

See also

• highlightOptions

• SceneView.highlightOptions
• MapView.highlightOptions

• Sample: Highlight point features

Examples

// highlight features based on a query result
let highlight;
view.whenLayerView(treesLayer).then(function(layerView){
  layerView.highlightOptions = {
    color: "#FF00FF", //bright fuschia
    haloOpacity: 0.8,
    fillOpacity: 0.3
  };
  let query = treesLayer.createQuery();
  query.where = "type = 'Quercus'";
  treesLayer.queryFeatures(query).then(function(result){
    highlight?.remove();
    highlight = layerView.highlight(result.features);
  });
});

// highlight feature on pointer-move
view.on("pointer-move", function(event){
  view.hitTest(event).then(function(response){
    if (response.results.length) {
      let graphic = response.results.filter(function (result) {
        return result.graphic.layer === treesLayer;
      })[0].graphic;

     view.whenLayerView(graphic.layer).then(function(layerView){
       layerView.highlight(graphic);
     });
    }
  });
});

isFulfilled(){Boolean}inherited

isFulfilled() may be used to verify if creating an instance of the class is fulfilled (either resolved or rejected). If it is fulfilled, true will be returned.

Returns

Type	Description
Boolean	Indicates whether creating an instance of the class has been fulfilled (either resolved or rejected).

isRejected(){Boolean}inherited

isRejected() may be used to verify if creating an instance of the class is rejected. If it is rejected, true will be returned.

Returns

Type	Description
Boolean	Indicates whether creating an instance of the class has been rejected.

isResolved(){Boolean}inherited

isResolved() may be used to verify if creating an instance of the class is resolved. If it is resolved, true will be returned.

Returns

Type	Description
Boolean	Indicates whether creating an instance of the class has been resolved.

queryAggregates(query, options){Promise<FeatureSet>}

Since: ArcGIS Maps SDK for JavaScript 4.25

Executes a Query against aggregate features (i.e. clusters or bins) available for drawing in the layerView and returns a FeatureSet. If query parameters are not provided, all aggregates available for drawing are returned along with their attributes that are available on the client. Fields referenced in statistic queries or in the where clause must first be defined as aggregate fields.

Known Limitations

This method currently does not support spatial queries (i.e. the Query.geometry option and its related properties).

Parameters

query Query autocast optional Autocasts from Object Specifies the parameters of the query. Leave this parameter empty to query all aggregates in the view.

options Object optional An object with the following properties. Specification signal AbortSignal optional Signal object that can be used to abort the asynchronous task. The returned promise will be rejected with an Error named AbortError when an abort is signaled. See also AbortController for more information on how to construct a controller that can be used to deliver abort signals.

Returns

Type	Description
Promise<FeatureSet>	When resolved, returns a FeatureSet containing an array of aggregate features.

See also

• FeatureReductionBinning
• FeatureReductionCluster
• Graphic.isAggregate

Example

// clustered point layer
const layer = new FeatureLayer({
  featureReduction: { type: "cluster" }
});

const layerView = await view.whenLayerView(layer);
await reactiveUtils.whenOnce(() => !layerView.updating);

// features represents all the clusters in the view
const { features } = await layerView.queryAggregates();

queryExtent(query, options){Promise<object>}

Executes a Query against features available for drawing in the layerView and returns the Extent of features that satisfy the query.

Known Limitations

• Spatial queries have the same limitations as those listed in the projection engine documentation.
• Spatial queries are not currently supported if the layerView has any of the following SpatialReferences:
  • GDM 2000 (4742) – Malaysia
  • Gusterberg (Ferro) (8042) – Austria/Czech Republic
  • ISN2016 (8086) - Iceland
  • SVY21 (4757) - Singapore

Parameters

query Query autocast optional Autocasts from Object Specifies the attributes and spatial filter of the query. When no parameters are passed to this method, all features in the client are returned. To only return features visible in the view, set the geometry parameter in the query object to the view's extent.

options Object optional An object with the following properties. Specification signal AbortSignal optional Signal object that can be used to abort the asynchronous task. The returned promise will be rejected with an Error named AbortError when an abort is signaled. See also AbortController for more information on how to construct a controller that can be used to deliver abort signals.

Returns

Type	Description
Promise<object>	When resolved, returns the extent and count of the features that satisfy the input query. See the object specification table below for details. Property Type Description count Number The number of features that satisfy the input query. extent Extent The extent of the features that satisfy the query.

Examples

let layer = new CSVLayer({
  url: csvUrl  // URL to a csv file
});

const layerView = await view.whenLayerView(layer);
await reactiveUtils.whenOnce(() => !layerView.updating);

const results = await layerView.queryExtent()
view.goTo(results.extent);  // go to the extent of all the graphics in the layerView

// Expand the extent so that a feature (i.e. point feature)
// won't be off screen after the end of goTo animation.
const { extent } = await layerView.queryExtent()
const zoomScale = 16000;
extent.expand((zoomScale / view.scale) * view.resolution);
view.goTo(extent);

queryFeatureCount(query, options){Promise<number>}

Executes a Query against features available for drawing in the layerView and returns the number of features that satisfy the query. If query parameters are not provided, the count of all features available for drawing is returned.

Known Limitations

• Spatial queries have the same limitations as those listed in the projection engine documentation.
• Spatial queries are not currently supported if the layerView has any of the following SpatialReferences:
  • GDM 2000 (4742) – Malaysia
  • Gusterberg (Ferro) (8042) – Austria/Czech Republic
  • ISN2016 (8086) - Iceland
  • SVY21 (4757) - Singapore

Parameters

query Query autocast optional Autocasts from Object Specifies the attributes and spatial filter of the query. When no parameters are passed to this method, all features in the client are returned. To only return features visible in the view, set the geometry parameter in the query object to the view's extent.

options Object optional An object with the following properties. Specification signal AbortSignal optional Signal object that can be used to abort the asynchronous task. The returned promise will be rejected with an Error named AbortError when an abort is signaled. See also AbortController for more information on how to construct a controller that can be used to deliver abort signals.

Returns

Type	Description
Promise<number>	When resolved, returns the number of features satisfying the query.

Examples

view.on("click", (event) => {
  let query = new Query();
  query.geometry = event.mapPoint;  // obtained from a view click event
  query.spatialRelationship = "intersects";

  const layerView = await view.whenLayerView(layer);
  await reactiveUtils.whenOnce(() => !layerView.updating);

  const count = await layerView.queryFeatureCount(query);
  console.log(count);  // prints the number of the client-side graphics that satisfy the query
});

const layerView = await view.whenLayerView(layer);
const count = await layerView.queryFeatureCount()
console.log(count);  // prints the total number of client-side graphics to the console

queryFeatures(query, options){Promise<FeatureSet>}

Executes a Query against features available for drawing in the layerView and returns a FeatureSet. If query parameters are not provided, then a default query is created using createQuery() method and all features that pass the layer view filter are returned along with their attributes that are available on the client. For client-side attribute queries, relevant fields should exist in availableFields list for the query to be successful.

To execute a query against all the features in a layer rather than only those in the client, you must use the queryFeatures() method on the layer.

Known Limitations

• Attribute values used in attribute queries executed against layerViews are case sensitive.
• Spatial queries are executed against quantized geometries in the layerView. The resolution of layerView geometries, is only as precise as the scale resolution of the view. Therefore, the results of the same query could be different when executed at different scales. This also means that geometries returned from any layerView query will likewise be at the same scale resolution of the view.
• Spatial queries have the same limitations as those listed in the projection engine documentation.
• Spatial queries are not currently supported if the FeatureLayerView has any of the following SpatialReferences:
  • GDM 2000 (4742) – Malaysia
  • Gsterberg (Ferro) (8042) – Austria/Czech Republic
  • ISN2016 (8086) - Iceland
  • SVY21 (4757) - Singapore

Parameters

query Query autocast optional Autocasts from Object Specifies the attributes and spatial filter of the query. When this parameter is not passed to queryFeatures() method, then a default query is created using createQuery() method and all features that pass the layer view filter are returned along with their attributes that are available on the client. To only return features visible in the view, set the geometry parameter in the query object to the view's extent.

options Object optional An object with the following properties. Specification signal AbortSignal optional Signal object that can be used to abort the asynchronous task. The returned promise will be rejected with an Error named AbortError when an abort is signaled. See also AbortController for more information on how to construct a controller that can be used to deliver abort signals.

Returns

Type	Description
Promise<FeatureSet>	When resolved, a FeatureSet containing an array of graphic features is returned.

See also

• Sample - Query statistics client-side by distance

• Sample - Query statistics by geometry

• Sample - Query statistics client-side

• Query and filter guide

Examples

let layer = new FeatureLayer({
  url: fsUrl  // points to a Feature Service layer url
});

let query = new Query();
query.geometry = new Extent({
 xmin: -9177811,
 ymin: 4247000,
 xmax: -9176791,
 ymax: 4247784,
 spatialReference: 102100
});
query.spatialRelationship = "intersects";

const layerView = await view.whenLayerView(layer);
await reactiveUtils.whenOnce(() => !layerView.updating);

const results = await layerView.queryFeatures(query);
console.log(results.features);  // prints the array of client-side graphics to the console

let layer = new FeatureLayer({
  url: fsUrl  // points to a Feature Service layer url
});

// returns all the graphics from the layerView
const layerView = await view.whenLayerView(layer);
await reactiveUtils.whenOnce(() => !layerView.updating);

const results = await layerView.queryFeatures()
console.log(results.features); // prints all the client-side graphics to the console

layerView.queryFeatures({
  geometry: mapPoint,
  // 6 pixels around a point at the view resolution to query around a finger.
  distance: view.resolution * 6,
});

queryObjectIds(query, options){Promise<number[]>}

Executes a Query against features available for drawing in the layerView and returns array of the ObjectIDs of features that satisfy the input query. If query parameters are not provided, the ObjectIDs of all features available for drawing are returned.

Known Limitations

• Spatial queries have the same limitations as those listed in the projection engine documentation.
• Spatial queries are not currently supported if the layerView has any of the following SpatialReferences:
  • GDM 2000 (4742) – Malaysia
  • Gusterberg (Ferro) (8042) – Austria/Czech Republic
  • ISN2016 (8086) - Iceland
  • SVY21 (4757) - Singapore

Parameters

query Query autocast optional Autocasts from Object Specifies the attributes and spatial filter of the query. When no parameters are passed to this method, all features in the client are returned. To only return features visible in the view, set the geometry parameter in the query object to the view's extent.

options Object optional An object with the following properties. Specification signal AbortSignal optional Signal object that can be used to abort the asynchronous task. The returned promise will be rejected with an Error named AbortError when an abort is signaled. See also AbortController for more information on how to construct a controller that can be used to deliver abort signals.

Returns

Type	Description
Promise<number[]>	When resolved, returns an array of numbers representing the ObjectIDs of the features satisfying the query.

Examples

view.on("click", async (event) => {
  let query = new Query();
  query.geometry = event.mapPoint;  // obtained from a view click event
  query.spatialRelationship = "intersects";

  const layerView = await view.whenLayerView(layer)
  await reactiveUtils.whenOnce(() => !layerView.updating);

  const ids = await layerView.queryObjectIds(query);
  console.log(ids);  // prints the ids of the client-side graphics to the console=
});

// returns all the Ids from the graphics in the layerView
view.whenLayerView(layer).then(function(layerView){
  return layerView.queryObjectIds()
}).then(function(ids){
  console.log(ids);  // prints the ids of all the client-side graphics to the console
});

removeHandles(groupKey)inherited

Since: ArcGIS Maps SDK for JavaScript 4.25

Removes a group of handles owned by the object.

Parameter

groupKey * optional A group key or an array or collection of group keys to remove.

Example

obj.removeHandles(); // removes handles from default group

obj.removeHandles("handle-group");
obj.removeHandles("other-handle-group");

when(callback, errback){Promise}inherited

when() may be leveraged once an instance of the class is created. This method takes two input parameters: a callback function and an errback function. The callback executes when the instance of the class loads. The errback executes if the instance of the class fails to load.

Parameters

callback Function optional The function to call when the promise resolves.

errback Function optional The function to execute when the promise fails.

Returns

Type	Description
Promise	Returns a new promise for the result of callback that may be used to chain additional functions.

Example

// Although this example uses MapView, any class instance that is a promise may use when() in the same way
let view = new MapView();
view.when(function(){
  // This function will execute once the promise is resolved
}, function(error){
  // This function will execute if the promise is rejected due to an error
});