Property Overview

Property Details

capabilities Objectreadonly

Describes the layer's supported capabilities.

Properties:

data Object Describes characteristics of the data in the layer. Specification: supportsAttachment Boolean Indicates if the attachment is enabled on the layer. At this current time, the GeoJSONLayer doesn’t support attachments. supportsM Boolean Indicates if the features in the layer support M values. Requires ArcGIS Server service 10.1 or greater. supportsZ Boolean Indicates if the features in the layer support Z values. Requires ArcGIS Server service 10.1 or greater. See elevationInfo for details regarding placement and rendering of features with z-values in 3D SceneViews.

editing Object Describes editing capabilities that can be performed on the features in the layer. Specification: supportsDeleteByAnonymous Boolean Indicates if anonymous users can delete features created by others. supportsDeleteByOthers Boolean Indicates if logged in users can delete features created by others. supportsGeometryUpdate Boolean Indicates if the geometry of the features in the layer can be edited. supportsGlobalId Boolean Indicates if the globalid values provided by the client are used in applyEdits. supportsRollbackOnFailure Boolean Indicates if the rollbackOnFailure parameter can be set to true or false when running the synchronizeReplica operation. supportsUpdateByAnonymous Boolean Indicates if anonymous users can update features created by others. supportsUpdateByOthers Boolean Indicates if logged in users can update features created by others. supportsUpdateWithoutM Boolean Indicates if m-values must be provided when updating features. supportsUploadWithItemId Boolean Indicates if the layer supports uploading attachments by UploadId.

operations Object Describes operations that can be performed on features in the layer. Specification: supportsAdd Boolean Indicates if new features can be added to the layer. supportsDelete Boolean Indicates if features can be deleted from the layer. supportsUpdate Boolean Indicates if features in the layer can be updated. supportsEditing Boolean Indicates if features in the layer can be edited. Use supportsAdd, supportsUpdate and supportsDelete to determine which editing operations are supported. supportsCalculate Boolean Indicates if values of one or more field values in the layer can be updated. See the Calculate REST operation document for more information. supportsQuery Boolean Indicates if features in the layer can be queried. supportsQueryAttachments Boolean Indicates if the layer supports REST API queryAttachments operation, which is supported with hosted feature services at version 10.5 and greater. If false, queryAttachments() method can only return attachments for one feature at a time. If true, queryAttachments() can return attachments for array of objectIds. supportsValidateSql Boolean Indicates if the layer supports a SQL-92 expression or where clause. This operation is only supported in ArcGIS Online hosted feature services. supportsResizeAttachments Boolean Indicates if resized attachments are supported in the layer. This is useful for showing thumbnails in Popups.

query Object Describes query operations that can be performed on features in the layer. Specification: supportsCentroid Boolean Indicates if the geometry centroid associated with each polygon feature can be returned. This operation is only supported in ArcGIS Online hosted feature services. supportsDistance Boolean Indicates if the layer's query operation supports a buffer distance for input geometries. supportsDistinct Boolean Indicates if the layer supports queries for distinct values based on fields specified in the outFields. supportsDisjointSpatialRelationship Boolean Indicates if the query operation supports disjoint spatial relationship. This is valid only for hosted feature services. supportsExtent Boolean Indicates if the layer's query response includes the extent of features. At 10.3, this option is only available for hosted feature services. At 10.3.1, it is available for hosted and non-hosted feature services. supportsGeometryProperties Boolean Indicates if the layer's query response contains geometry attributes, including shape area and length attributes. This operation is only supported in ArcGIS Online hosted feature services. supportsHavingClause Boolean Indicates if the layer supports the having clause on the service. Requires an ArcGIS Server service 10.6.1 or greater. supportsOrderBy Boolean Indicates if features returned in the query response can be ordered by one or more fields. Requires an ArcGIS Server service 10.3 or greater. supportsPagination Boolean Indicates if the query response supports pagination. Requires an ArcGIS Server service 10.3 or greater. supportsQueryGeometry Boolean Indicates if the query response includes the query geometry. This is valid only for hosted feature services. supportsQuantization Boolean Indicates if the query operation supports the projection of geometries onto a virtual grid. Requires an ArcGIS Server service 10.6.1 or greater. supportsQuantizationEditMode Boolean Indicates if the query operation supports quantization designed to be used in edit mode (highest resolution at the given spatial reference). Requires an ArcGIS Server service 10.6.1 or greater. supportsResultType Boolean Indicates if the number of features returned by the query operation can be controlled. supportsSqlExpression Boolean Indicates if the query operation supports SQL expressions. supportsStandardizedQueriesOnly Boolean Indicates if the query operation supports using standardized queries. Learn more about standardized queries here. supportsStatistics Boolean Indicates if the layer supports field-based statistical functions. Requires ArcGIS Server service 10.1 or greater. supportsHistoricMoment Boolean Indicates if the layer supports historic moment query. Requires ArcGIS Server service 10.5 or greater.

queryRelated Object Indicates if the layer's query operation supports querying features or records related to features in the layer. Specification: supportsCount Boolean Indicates if the layer's query response includes the number of features or records related to features in the layer. supportsOrderBy Boolean Indicates if the related features or records returned in the query response can be ordered by one or more fields. Requires ArcGIS Server service 10.3 or greater. supportsPagination Boolean Indicates if the query response supports pagination for related features or records. Requires ArcGIS Server service 10.3 or greater.

Example:

// Once the layer loads, check if the
// supportsAdd operations is enabled on the layer
geoJSONLayer.when(function(){
  if (geoJSONLayer.capabilities.operations.supportsAdd) {
    // if new features can be created in the layer
    // set up the UI for editing
    setupEditing();
  }
});

copyright String

Copyright information for the layer.

declaredClass Stringreadonly inherited

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

definitionExpression String

The SQL where clause used to filter features on the client. Only the features that satisfy the definition expression are displayed in the View. Definition expressions may be set when a layer is constructed prior to it loading in the view or after it has been added to the map. If the definition expression is set after the layer has been added to the map, the view will automatically refresh itself to display the features that satisfy the new definition expression.

Examples:

// Set definition expression in constructor to only display earthquakes magnitude 5.0 and greater
const layer = new GeoJSONLayer({
  url: "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_month.geojson",
  definitionExpression: "mag >= 5"
});

// Set the definition expression directly on layer instance after it has loaded
layer.definitionExpression = "mag >= 5";

displayField String

The name of the layer's primary display field. The value of this property matches the name of one of the fields of the layer.

elevationInfo Object

Specifies how graphics are placed on the vertical axis (z). This property may only be used in a SceneView. See the ElevationInfo sample for an example of how this property may be used.

Properties:

mode String Defines how the graphic is placed with respect to the terrain surface. See the table below for a list of possible values. Mode Description on-the-ground Graphics are draped on the terrain surface. This is the default value for Point geometries rendered with ObjectSymbol3DLayers. relative-to-ground Graphics are placed at an elevation relative to the terrain surface. The graphic's elevation is determined by summing up the terrain elevation and the result of featureExpressionInfo (if defined). This is the default value for Point geometries rendered with IconSymbol3DLayers. absolute-height Graphics are placed at an absolute elevation (z-value) above sea level. This z-value is determined by the result of featureExpressionInfo (if defined). This mode doesn't take the elevation of the terrain into account. relative-to-scene Features are aligned to extruded polygons and objects part of 3D Object SceneLayers or IntegratedMeshLayers, depending on which has higher elevation. If the graphic is not directly above a building or any other feature, it is aligned to the terrain surface elevation. If defined, the result of featureExpressionInfo is added to the 3D Object/terrain surface elevation. Possible Values:"on-the-ground"|"relative-to-ground"|"absolute-height"|"relative-to-scene"

offset Number optional An elevation offset, which is added to the vertical position of the graphic. If unit is not defined, the offset is in meters. When mode = "on-the-ground", this property has no effect.

featureExpressionInfo Object optional This object contains information about setting a custom z-value on the feature. Specification: expression String optional An Arcade expression evaluating to a number that determines the z-value of the feature. When mode = "on-the-ground", this property has no effect. For line and polygon geometries the result of the expression is the same for all vertices of a feature.

unit String optional The unit for featureExpressionInfo and offset values. Possible Values:"feet"|"meters"|"kilometers"|"miles"|"us-feet"|"yards"

featureReduction FeatureReductionCluster|FeatureReductionSelectionautocast

Configures the method for reducing the number of point features in the view. By default this property is null, which indicates the layer view should draw every feature.

There are two types of feature reduction: selection and cluster.

• Selection only applies to points in a SceneView and involves thinning overlapping features so no features intersect on screen. This has been available since version 4.4.
• Cluster spatially groups points in a MapView into clusters. The size of each cluster is proportional to the number of features within the cluster. This has been available since version 4.14.

See also:

• Sample - Point clustering

• Sample - Point clustering with visual variables

• Sample - Filter clustered points

• Sample - Point styles for cities

Examples:

// clusters points based on their spatial proximity to other points
layer.featureReduction = {
  type: "cluster",
  clusterRadius: 100
};

// thins features in the view
layer.featureReduction = {
  type: "selection"
};

fields Field[]autocast

Autocasts from Object[]

An array of fields in the layer.

Example:

// define each field's schema
var fields = [
 new Field({
   "name": "ObjectID",
   "alias": "ObjectID",
   "type": "oid"
 }), new Field({
   "name": "description",
   "alias": "Description",
   "type": "string"
 }), new Field ({
   "name": "title",
   "alias": "Title",
   "type": "string"
 })
];

fieldsIndex FieldsIndexreadonly

Since: ArcGIS API for JavaScript 4.12

A convenient property that can be used to make case-insensitive lookups for a field by name. It can also provide a list of the date fields in a layer.

Example:

// lookup a field by name. name is case-insensitive
const field = layer.fieldsIndex.get("SoMeFiEld");

if (field) {
  console.log(field.name); // SomeField
}

fullExtent Extentautocast inherited

The full extent of the layer. By default, this is worldwide. This property may be used to set the extent of the view to match a layer's extent so that its features appear to fill the view. See the sample snippet below.

Example:

// Once the layer loads, set the view's extent to the layer's fullextent
layer.when(function(){
  view.extent = layer.fullExtent;
});

geometryType String

The geometry type of features in the layer. All features must be of the same type.

Possible Values:"point"|"polygon"|"polyline"|"multipoint"

hasZ Booleanreadonly

Indicates whether the client-side features in the layer have Z (elevation) values. Refer to elevationInfo for details regarding placement and rendering of features with z-values in 3D SceneViews. Use the supportsZ property in the layer's capabilities.data object to verify if Z values are supported on the features.

Default Value:undefined

id String inherited

The unique ID assigned to the layer. If not set by the developer, it is automatically generated when the layer is loaded.

labelingInfo LabelClass[]autocast

Autocasts from Object[]

The label definition for this layer, specified as an array of LabelClass. Use this property to specify labeling properties for the layer such as label expression, placement, and size.

Multiple Label classes with different where clauses can be used to define several labels with varying styles on the same feature. Likewise, multiple label classes may be used to label different types of features (for example blue labels for lakes and green labels for parks).

Known Limitations

• Currently only one LabelClass is supported in 3D SceneViews.

See also:

• Sample: Add multiple label classes to a layer

• Sample: Multi-line labels

• Sample: Flat vs. volumetric 3D symbol layers

Example:

const statesLabelClass = new LabelClass({
  labelExpressionInfo: { expression: "$feature.NAME" },
  symbol: {
    type: "text",  // autocasts as new TextSymbol()
    color: "black",
    haloSize: 1,
    haloColor: "white"
  }
});
geoJSONLayer.labelingInfo = [ statesLabelClass ];

labelsVisible Boolean

Indicates whether to display labels for this layer. If true, labels will appear as defined in the labelingInfo property.

Known Limitations

• Currently 3D SceneViews only support one LabelClass per feature.

Default Value:true

legendEnabled Boolean

Indicates whether the layer will be included in the legend.

Default Value:true

listMode String inherited

Indicates how the layer should display in the LayerList widget. The possible values are listed below.

Value	Description
show	The layer is visible in the table of contents.
hide	The layer is hidden in the table of contents.
hide-children	If the layer is a GroupLayer, BuildingSceneLayer, KMLLayer, MapImageLayer, TileLayer or WMSLayer, hide the children layers from the table of contents.

Possible Values:"show"|"hide"|"hide-children"

Default Value:show

loaded Booleanreadonly inherited

Indicates whether the layer's resources have loaded. When true, all the properties of the object can be accessed.

Default Value:false

loadError Errorreadonly inherited

The Error object returned if an error occurred while loading.

Default Value:null

loadStatus Stringreadonly inherited

Represents the status of a load operation.

Value	Description
not-loaded	The object's resources have not loaded.
loading	The object's resources are currently loading.
loaded	The object's resources have loaded without errors.
failed	The object's resources failed to load. See loadError for more details.

Possible Values:"not-loaded"|"loading"|"failed"|"loaded"

Default Value:not-loaded

loadWarnings Object[]readonly inherited

A list of warnings which occurred while loading.

maxScale Number

The maximum scale (most zoomed in) at which the layer is visible in the view. If the map is zoomed in beyond this scale, the layer will not be visible. A value of 0 means the layer does not have a maximum scale. The maxScale value should always be smaller than the minScale value, and greater than or equal to the service specification.

Default Value:0

Examples:

// The layer will not be visible when the view is zoomed in beyond a scale of 1:1,000
layer.maxScale = 1000;

// The layer's visibility is not restricted to a maximum scale.
layer.maxScale = 0;

minScale Number

The minimum scale (most zoomed out) at which the layer is visible in the view. If the map is zoomed out beyond this scale, the layer will not be visible. A value of 0 means the layer does not have a minimum scale. The minScale value should always be larger than the maxScale value, and lesser than or equal to the service specification.

Default Value:0

Examples:

// The layer will not be visible when the view is zoomed out beyond a scale of 1:3,000,000
layer.minScale = 3000000;

// The layer's visibility is not restricted to a minimum scale.
layer.minScale = 0;

objectIdField String

The name of an oid field containing a unique value or identifier for each feature in the layer. id property of the feature object in the GeoJSON will be used as ObjectID. If id property is not present and objectIDField is not specified, ObjectID field will be generated for each feature.

See also:

• fields

opacity Number inherited

The opacity of the layer. This value can range between 1 and 0, where 0 is 100 percent transparent and 1 is completely opaque.

Default Value:1

Example:

// Makes the layer 50% transparent
layer.opacity = 0.5;

popupEnabled Boolean

Indicates whether to display popups when features in the layer are clicked. The layer needs to have a popupTemplate to define what information should be displayed in the popup. Alternatively, a default popup template may be automatically used if Popup.defaultPopupTemplateEnabled is set to true.

Default Value:true

See also:

• createPopupTemplate

• View

popupTemplate PopupTemplateautocast

The popup template for the layer. When set on the layer, the popupTemplate allows users to access attributes and display their values in the view's popup when a feature is selected using text and/or charts. See the PopupTemplate sample for an example of how PopupTemplate interacts with a FeatureLayer.

A default popup template is automatically used if no popupTemplate has been defined when Popup.defaultPopupTemplateEnabled is set to true.

See also:

• createPopupTemplate

• View

renderer Rendererautocast

The renderer assigned to the layer. The renderer defines how to visualize each feature in the layer. Depending on the renderer type, features may be visualized with the same symbol, or with varying symbols based on the values of provided attribute fields or functions. If not specified, a default renderer will be generated based on the geometry type.

screenSizePerspectiveEnabled Boolean

Apply perspective scaling to screen-size point symbols in a SceneView. When true, screen sized objects such as icons, labels or callouts integrate better in the 3D scene by applying a certain perspective projection to the sizing of features. This only applies when using a SceneView.

layer.screenSizePerspectiveEnabled = true

layer.screenSizePerspectiveEnabled = false

Known Limitations

Screen size perspective is currently not optimized for situations where the camera is very near the ground, or for scenes with point features located far from the ground surface. In these cases it may be better to turn off screen size perspective. As screen size perspective changes the size based on distance to the camera, it should be set to false when using size visual variables.

Default Value:true

spatialReference SpatialReferenceautocast

The spatial reference of the layer. The default value is WGS84. This property can be set explicitly to project the longitude and latitude coordinates when the layer parses the GeoJSON file. While not required, explicitly setting the spatial reference of the layer will improve the performance when projecting to a spatial reference other than the one used by the coordinates in the raw data.

Default Value:SpatialReference.WGS84

See also:

• SpatialReference.WGS84

Example:

const geoJSONLayer = new GeoJSONLayer({
  url: "example.geojson",
  spatialReference: {
    wkid: 5936
  }
});

templates FeatureTemplate[]

An array of feature templates defined in the layer. See ArcGIS Pro subtypes document.

timeExtent TimeExtentautocast

Since: ArcGIS API for JavaScript 4.14

The layer's time extent. When the layer's useViewTime is false, the layer instructs the view to show data from the layer based on this time extent. If the useViewTime is true, then this property has no effect on the layer, because the layer will show the data within the view's timeExtent property.

Default Value:null

Examples:

if (!layer.useViewTime) {
  if (layer.timeExtent) {
    console.log("Current timeExtent:", layer.timeExtent.start, " - ", layer.timeExtent.end}
  } else {
    console.log("The layer will display data within the view's timeExtent.");
    console.log("Current view.timeExtent:", view.timeExtent.start, " - ", view.timeExtent.end}
  }
}

// set the timeExtent on the layer and useViewTime false
// In this case, the layer will honor its timeExtent and ignore
// the view's timeExtent
const layer = new ImageryLayer({
  url: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/ScientificData/SeaTemperature/ImageServer",
  timeExtent: {
    start: new Date(2014, 4, 18),
    end: new Date(2014, 4, 19)
  },
  useViewTime: false
});

timeInfo TimeInfoautocast

TimeInfo provides information such as date fields that store start and end time for each feature and the fullTimeExtent for the layer. The timeInfo property, along with its startField and endField properties, must be set at the time of layer initialization if it is being set for a GeoJSONLayer, CSVLayer or FeatureLayer initialized from client-side features. The fullTimeExtent for timeInfo is automatically calculated based on its startField and endField properties. The timeInfo parameters cannot be changed after the layer is loaded.

Default Value:null

Example:

// create geojson layer from usgs earthquakes geojson feed
const geojsonLayer = new GeoJSONLayer({
  url: "https://earthquake.usgs.gov/earthquakes/feed/v1.0/summary/all_month.geojson",
  copyright: "USGS Earthquakes",
  fields: [
    { "name": "mag", "type": "double" },
    { "name": "place", "type": "string" },
    { "name": "time", "type": "date" }, // date field
    { "name": "depth", "type": "double" }
  ],
  // timeInfo can be used to do temporal queries
  // set the startField and endField.
  // timeExtent is automatically calculated from the
  // the start and end date fields
  timeInfo: {
    startField: "time"
  }
});

timeOffset TimeIntervalautocast

Since: ArcGIS API for JavaScript 4.14

A temporary offset of the time data based on a certain TimeInterval. This allows users to overlay features from two or more time-aware layers with different time extents. For example, if a layer has data recorded for the year 1970, an offset value of 2 years would temporarily shift the data to 1972. You can then overlay this data with data recorded in 1972. A time offset can be used for display purposes only. The query and selection are not affected by the offset.

Default Value:null

Example:

// Offset a CSV Layer containing hurricanes from 2015 so that they appear in 2019 (+4 years).
var layer = new CSVLayer({
  url: `hurricanes-and-storms-2015.csv`,
  timeOffset: {
    value: 4,
    unit: "years"
  },
  timeInfo: {
    startField: "ISO_time"
  },
  renderer: {
    type: "simple",
    symbol: {
      type: "simple-marker",
      size: 6,
      color: "red",
      outline: {
        width: 0.5,
        color: "black"
      }
    }
  }
});

title String

The title of the layer used to identify it in places such as the Legend and LayerList widgets.

Default Value:"GeoJSON"

type Stringreadonly

For GeoJSONLayer the type is always "geojson".

url String

The URL of the GeoJSON file.

useViewTime Boolean

Since: ArcGIS API for JavaScript 4.14

Determines if the layer will update its temporal data based on the view's current timeExtent. When false, the layer will display its temporal data based on the layer's timeExtent, regardless of changes to the view.

Default Value:true

Example:

if (featureLayer.useViewTime) {
  console.log("Displaying data between:", view.timeExtent.start, " - ", view.timeExtent.end);
}

visible Boolean inherited

Indicates if the layer is visible in the View. When false, the layer may still be added to a Map instance that is referenced in a view, but its features will not be visible in the view.

Default Value:true

Example:

// The layer is no longer visible in the view
layer.visible = false;

Method Overview

Method Details

applyEdits(edits){Promise<Object>}

Applies edits to features in a layer. New features can be created and existing features can be updated or deleted on the cilent side. Feature geometries and/or attributes may be modified.

If client-side features are added, removed or updated at runtime using applyEdits() then use queryFeatures() to return updated features.

Parameters:

Specification:

edits Object Object containing features to be added, updated or deleted. Specification: addFeatures Graphic[]|Collection<Graphic> optional An array or a collection of features to be added. Values of non nullable fields must be provided when adding new features. Date fields must have numeric values representing universal time. updateFeatures Graphic[]|Collection<Graphic> optional An array or a collection of features to be updated. Each feature must have valid objectId. Values of non nullable fields must be provided when updating features. Date fields must have numeric values representing universal time. deleteFeatures Graphic[]|Object[]|Collection<Graphic> optional An array or a collection of features, or objects to be deleted. When an array or collection of features is passed, each feature must have a valid objectId. When an array of objects is used, each object must have a valid objectId property.

Returns:

Type	Description
Promise<Object>	Resolves to an object containing edit results. See the object specification table below for details. Property Type Description addFeatureResults FeatureEditResult[] Result of adding features. deleteFeatureResults FeatureEditResult[] Result of deleting features. updateFeatureResults FeatureEditResult[] Result of updating features.

See also:

• Sample - Edit features

Example:

function addFeature(geometry) {
  const attributes = {};
  attributes["Description"] = "This is the description";
  attributes["Address"] = "380 New York St";

  // Date.now() returns number of milliseconds elapsed
  // since 1 January 1970 00:00:00 UTC.
  attributes["Report_Date"] = Date.now();

  const addFeature =  new Graphic({
    geometry: geometry,
    attributes: attributes
  });

  const deleteFeature = {
   objectId: [467]
  };

  const promise = geoJSONLayer.applyEdits({
    addFeatures: [addFeature],
    deleteFeatures: [deleteFeature]
  });
}

cancelLoad()inherited

Cancels a load() operation if it is already in progress.

createLayerView(view, options){Promise<LayerView>}inherited

Called by the views, such as MapView and SceneView, when the layer is added to the Map.layers collection and a layer view must be created for it. This method is used internally and there is no use case for invoking it directly.

Parameters:

view * The parent view.

options Object optional An object specifying additional options. See the object specification table below for the required properties of this object. Specification: signal AbortSignal optional A signal to abort the creation of the layerview.

Returns:

Type	Description
Promise<LayerView>	Resolves with a LayerView instance.

See also:

• Sample - Custom WebGL layer view

createPopupTemplate(options){PopupTemplate}

Creates a popup template for the layer, populated with all the fields of the layer.

Parameters:

Specification:

options Object optional Options for creating the popup template. Specification: maximumFields Number optional Default Value: 75 The maximum number of fields to include in the popup template. ignoreFieldTypes String[] optional Field types to ignore when creating the popup. By default the geometry, blob, raster, guid and xml field types are ignored.

Returns:

Type	Description
PopupTemplate	The popup template, or null if the layer does not have any fields.

createQuery(){Query}

Creates query parameter object that can be used to fetch features that satisfy the layer's configurations such as definitionExpression. It will return Z and M values based on the layer's data capabilities. It sets the query parameter's outFields property to ["*"].

Returns:

Type	Description
Query	The query object representing the layer's definition expression and other configurations.

See also:

• Sample - Query features from a FeatureLayer

Example:

// Get a query object for the layer's current configuration
// queryParams.outFields will be set to ["*"] to get values
// for all available fields.
const queryParams = layer.createQuery();
// set a geometry for filtering features by a region of interest
queryParams.geometry = extentForRegionOfInterest;
// Add to the layer's current definitionExpression
queryParams.where = queryParams.where + " AND TYPE = 'Extreme'";

// query the layer with the modified params object
layer.queryFeatures(queryParams).then(function(results){
  // prints the array of result graphics to the console
  console.log(results.features);
});

emit(type, event){Boolean}inherited

Emits an event on the instance. This method should only be used when creating subclasses of this class.

Parameters:

type String The name of the event.

event Object optional The event payload.

Returns:

Type	Description
Boolean	true if a listener was notified

getField(fieldName){Field}

Returns the Field instance for a field name (case-insensitive).

Parameter:

fieldName String Name of the field.

Returns:

Type	Description
Field	the matching field or undefined

See also:

• fields

getFieldDomain(fieldName, options){Domain}

Returns the Domain associated with the given field name. The domain can be either a CodedValueDomain or RangeDomain.

Parameters:

fieldName String Name of the field.

options Object optional An object specifying additional options. See the object specification table below for the required properties of this object. Specification: feature Graphic The feature to which the Domain is assigned.

Returns:

Type	Description
Domain	The Domain object associated with the given field name for the given feature.

hasEventListener(type){Boolean}inherited

Indicates whether there is an event listener on the instance that matches the provided event name.

Parameter:

type String The name of the event.

Returns:

Type	Description
Boolean	Returns true if the class supports the input event.

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.

load(signal){Promise}inherited

Loads the resources referenced by this class. This method automatically executes for a View and all of the resources it references in Map if the view is constructed with a map instance.

This method must be called by the developer when accessing a resource that will not be loaded in a View.

It's possible to provide a signal to stop being interested into a Loadable instance load status. When the signal is aborted, the instance does not stop its loading process, only cancelLoad can abort it.

Parameter:

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	Resolves when the resources have loaded.

on(type, listener){Object}inherited

Registers an event handler on the instance. Call this method to hook an event with a listener.

Parameters:

type String|String[] A event type, or an array of event types, to listen for.

listener Function The function to call when the event is fired.

Returns:

Type	Description
Object	Returns an event handler with a remove() method that can be called to stop listening for the event(s). Property Type Description remove Function When called, removes the listener from the event.

Example:

view.on("click", function(event){
  // event is the event handle returned after the event fires.
  console.log(event.mapPoint);
});

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

Executes a Query against the layer and returns the Extent of features that satisfy the query. If no parameters are specified, then the extent and count of all features satisfying the layer's configuration/filters 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 layer view 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. If no parameters are specified, then the extent and count of all features satisfying the layer's configuration/filters are returned.

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:

// Queries for the extent of all features matching the layer's configurations
// e.g. definitionExpression
layer.queryExtent().then(function(results){
  // go to the extent of the results satisfying the query
  view.goTo(results.extent);
});

const layer = new GeoJSONLayer({
  url: dataUrl
});

const query = new Query();
query.where = "region = 'Southern California'";

layer.queryExtent(query).then(function(results){
  view.goTo(results.extent);  // go to the extent of the results satisfying the query
});

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

Executes a Query against the layer and returns the number of features that satisfy the query. If no parameters are specified, the total number of features satisfying the layer's configuration/filters 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 layer view 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. If no parameters are specified, the total number of features satisfying the layer's configuration/filters is returned.

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 the number of features satisfying the query.

Examples:

// Queries for the count of all features matching the layer's configurations
// e.g. definitionExpression
layer.queryFeatureCount().then(function(numFeatures){
  // prints the total count to the console
  console.log(numFeatures);
});

const layer = new GeoJSONLayer({
  url: dataUrl
});

const query = new Query();
query.where = "region = 'Southern California'";

layer.queryFeatureCount(query).then(function(numResults){
  console.log(numResults);  // prints the number of results satisfying the query
});

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

Executes a Query against the layer and returns a FeatureSet, which can be accessed using the .then() method once the promise resolves. A FeatureSet contains an array of Graphic features, which can be added to the view's graphics. This array will not be populated if zero results are found.

Known Limitations

• Attribute values used in attribute queries executed against layer views are case sensitive.
• Spatial queries have the same limitations as those listed in the projection engine documentation.
• Spatial queries are not currently supported if the layer view 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. If no parameters are specified, then all features satisfying the layer's configuration/filters are returned.

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 features from a FeatureLayer

Examples:

// Queries for all the features matching the layer's configurations
// e.g. definitionExpression
layer.queryFeatures().then(function(results){
  // prints the array of result graphics to the console
  console.log(results.features);
});

const layer = new GeoJSONLayer({
  url: geojsonUrl  // points to a GeoJSON data url
});

const query = new Query();
query.where = "STATE_NAME = 'Washington'";
query.outSpatialReference = { wkid: 102100 };
query.returnGeometry = true;
query.outFields = [ "CITY_NAME" ];

layer.queryFeatures(query).then(function(results){
  console.log(results.features);  // prints the array of features to the console
});

// Get a query object for the layer's current configuration
const queryParams = layer.createQuery();
// set a geometry for filtering features by a region of interest
queryParams.geometry = extentForRegionOfInterest;
// Add to the layer's current definitionExpression
queryParams.where = queryParams.where + " AND TYPE = 'Extreme'";

// query the layer with the modified params object
layer.queryFeatures(queryParams).then(function(results){
  // prints the array of result graphics to the console
  console.log(results.features);
});

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

Executes a Query against the layer and returns an array of Object IDs for features that satisfy the input query. If no parameters are specified, then the Object IDs of all features satisfying the layer's configuration/filters 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 layer view 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. If no parameters are specified, then the Object IDs of all features satisfying the layer's configuration/filters are returned.

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 object IDs of the features satisfying the query.

Examples:

// Queries for all the Object IDs of features matching the layer's configurations
// e.g. definitionExpression
layer.queryObjectIds().then(function(results){
  // prints the array of Object IDs to the console
  console.log(results);
});

const layer = new GeoJSONLayer({
  url: dataUrl
});

const query = new Query();
query.where = "region = 'Southern California'";

layer.queryObjectIds(query).then(function(ids){
  console.log(ids);  // an array of object IDs
});

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 then() in the same way
var 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
});

Event Overview

{addedFeatures: Object[],deletedFeatures: Object[],updatedFeatures: Object[],}

{view: View,layerView: LayerView}

{view: View,error: Error}

{view: View,layerView: LayerView}

Event Details

edits

Since: ArcGIS API for JavaScript 4.13

Fires after applyEdits() is completed successfully. The event payload includes only successful edits, not the failed edits.

Properties:

addedFeatures Object[] An array of successfully added features. Specification: objectId Number Object Id of the feature that was added.

deletedFeatures Object[] An array of successfully deleted features. Specification: objectId Number Object Id of the feature that was deleted.

updatedFeatures Object[] An array of successfully updated features. Specification: objectId Number Object Id of the feature that was updated.

See also:

• applyEdits()

Example:

// This function will fire each time applyEdits() is completed successfully
geoJSONLayer.on("edits", function(event) {

  const extractObjectId = function(result) {
    return result.objectId;
  };

  const adds = event.addedFeatures.map(extractObjectId);
  console.log("addedFeatures: ", adds.length, adds);

  const updates = event.updatedFeatures.map(extractObjectId);
  console.log("updatedFeatures: ", updates.length, updates);

  const deletes = event.deletedFeatures.map(extractObjectId);
  console.log("deletedFeatures: ", deletes.length, deletes);
});

layerview-createinherited

Fires after the layer's LayerView is created and rendered in a view.

Properties:

view View The view in which the layerView was created.

layerView LayerView The LayerView rendered in the view representing the layer in layer.

See also:

• View.whenLayerView()

Example:

// This function will fire each time a layer view is created for this
// particular view.
layer.on("layerview-create", function(event){
  // The LayerView for the layer that emitted this event
  event.layerView;
});

layerview-create-errorinherited

Fires when an error emits during the creation of a LayerView after a layer has been added to the map.

Properties:

view View The view that failed to create a layerview for the layer emitting this event.

error Error An error object describing why the layer view failed to create.

See also:

• View.whenLayerView()

Example:

// This function fires when an error occurs during the creation of the layer's layerview
layer.on("layerview-create-error", function(event) {
  console.error("LayerView failed to create for layer with the id: ", layer.id, " in this view: ", event.view);
});

layerview-destroyinherited

Fires after the layer's LayerView is destroyed and no longer renders in a view.

Properties:

view View The view in which the layerView was destroyed.

layerView LayerView The destroyed LayerView representing the layer.