FeatureLayer

require(["esri/layers/FeatureLayer"], function(FeatureLayer){
  // points to the states layer in a service storing U.S. census data
  const fl = new FeatureLayer({
    url: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer/3"
  });
  map.add(fl);  // adds the layer to the map
});

// Add a non-spatial table.
require(["esri/layers/FeatureLayer"], function(FeatureLayer){
  // points to the non-spatial table in a service storing San Francisco crime incidents.
  const table = new FeatureLayer({
    url: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/SF311/FeatureServer/1"
  });
  table.load().then(function() {
     // table is loaded. ready to be queried on the server.
  });
});

// points to a hosted Feature Layer in ArcGIS Online
const fl = new FeatureLayer({
  portalItem: {  // autocasts as esri/portal/PortalItem
    id: "8444e275037549c1acab02d2626daaee"
  }
});
map.add(fl);  // adds the layer to the map

// points to a hosted table in ArcGIS Online
const table = new FeatureLayer({
  portalItem: { // autocasts as esri/portal/PortalItem
    id: "123f4410054b43d7a0bacc1533ceb8dc"
  }
});

// Before adding the table to the map, it must first be loaded and confirm it is the right type.
table.load().then(function() {
  if (table.isTable) {
    map.tables.add(table);
  }
});

const layer = new FeatureLayer({

   // create an instance of esri/layers/support/Field for each field object
   fields: [
   {
     name: "ObjectID",
     alias: "ObjectID",
     type: "oid"
   }, {
     name: "type",
     alias: "Type",
     type: "string"
   }, {
     name: "place",
     alias: "Place",
     type: "string"
   }],
   objectIdField: "ObjectID", // inferred from fields array if not specified
   geometryType: "point", // geometryType and spatialReference are inferred from the first feature
                          // in the source array if they are not specified.
   spatialReference: { wkid: 4326 },
   source: graphics,  //  an array of graphics with geometry and attributes
                     // popupTemplate and symbol are not required in each feature
                     // since those are handled with the popupTemplate and
                     // renderer properties of the layer
   popupTemplate: pTemplate,
   // a default simple renderer will be applied if not set.
   renderer: uvRenderer  // UniqueValueRenderer based on `type` attribute
});
map.add(layer);

// returns all the graphics from the layer view
view.whenLayerView(layer).then(function(layerView){
  layerView.watch("updating", function(val){
    if(!val){  // wait for the layer view to finish updating
      layerView.queryFeatures().then(function(results){
        console.log(results);  // prints all the client-side features to the console
      });
    }
  });
});

// Queries for all the features in the service (not the graphics in the view)
layer.queryFeatures().then(function(results){
  // prints an array of all the features in the service to the console
  console.log(results.features);
});

Property Overview

Property Details

apiKey String

Since: ArcGIS Maps SDK for JavaScript 4.20

An authorization string used to access a resource or service. API keys are generated and managed in the ArcGIS Developer dashboard. An API key is tied explicitly to an ArcGIS account; it is also used to monitor service usage. Setting a fine-grained API key on a specific class overrides the global API key.

Example

// set the api key to access a protected service
const layer = new FeatureLayer({
  url: serviceUrl,
  apiKey: "YOUR_API_KEY"
});

blendMode String

Since: ArcGIS Maps SDK for JavaScript 4.16

Blend modes are used to blend layers together to create an interesting effect in a layer, or even to produce what seems like a new layer. Unlike the method of using transparency which can result in a washed-out top layer, blend modes can create a variety of very vibrant and intriguing results by blending a layer with the layer(s) below it.

When blending layers, a top layer is a layer that has a blend mode applied. All layers underneath the top layer are background layers. The default blending mode is normal where the top layer is simply displayed over the background layer. While this default behavior is perfectly acceptable, the use of blend modes on layers open up a world of endless possibilities to generate creative maps.

The layers in a GroupLayer are blended together in isolation from the rest of the map.

In the following screenshots, the vintage shaded relief layer is displayed over a firefly world imagery layer. The color blend mode is applied to the vintage shaded relief and the result looks like a new layer.

Known Limitations

• The blendMode in 3D SceneViews is supported on BaseTileLayer, ImageryTileLayer, OpenStreetMapLayer, TileLayer, VectorTileLayer, WCSLayer, WebTileLayer, WMTSLayer and GroupLayer.
• The blendMode is not supported in the Legend.
• See print for known printing limitations.

The following factors will affect the blend result:

• Order of all layers
• Layer opacity
• Opacity of features in layers
• Visibility of layers
• By default, the very bottom layer in a map is drawn on a transparent background. You can change the MapView's background color.

Blend mode	Description
normal	The top layer is displayed over the background layer. The data of the top layer block the data of background layer where they overlap.
average	Takes the mathematical average of top and background layers. Result of average blend mode is often similar to the effect of setting the layer's opacity to 50%.

Lighten blend modes:

The following blend modes create lighter results than all layers. In lighten blend modes, pure black colors in the top layer become transparent allowing the background layer to show through. White in the top layer will stay unchanged. Any color that is lighter than pure black is going to lighten colors in the top layer to varying degrees all way to pure white.

Lighten blend modes can be useful when lightening dark colors of the top layer or removing black colors from the result. The plus, lighten and screen modes can be used to brighten layers that have faded or dark colors on a dark background.

Blend mode	Description
lighten	Compares top and background layers and retains the lighter color. Colors in the top layer become transparent if they are darker than the overlapping colors in the background layer allowing the background layer to show through completely. Can be thought of as the opposite of darken blend mode.
lighter	Colors in top and background layers are multiplied by their alphas (layer opacity and layer's data opacity. Then the resulting colors are added together. All overlapping midrange colors are lightened in the top layer. The opacity of layer and layer's data will affect the blend result.
plus	Colors in top and background layers are added together. All overlapping midrange colors are lightened in the top layer. This mode is also known as add or linear-dodge.
screen	Multiplies inverted colors in top and background layers then inverts the colors again. The resulting colors will be lighter than the original color with less contrast. Screen can produce many different levels of brightening depending on the luminosity values of the top layer. Can be thought of as the opposite of the multiply mode.
color-dodge	Divides colors in background layer by the inverted top layer. This lightens the background layer depending on the value of the top layer. The brighter the top layer, the more its color affects the background layer. Decreases the contrast between top and background layers resulting in saturated mid-tones and blown highlights.

Darken blend modes:

The following blend modes create darker results than all layers. In darken blend modes, pure white in the top layer will become transparent allowing the background layer to show through. Black in the top layer will stay unchanged. Any color that is darker than pure white is going to darken a top layer to varying degrees all the way to pure black.

The multiply blend mode is often used to highlight shadows, show contrast, or accentuate an aspect of a map. For example, you can use multiply blend mode on a topographic map displayed over hillshade when you want to have your elevation show through the topographic layer. See the intro to layer blending sample.

The multiply and darken modes can be used to have dark labels of the basemap to show through top layers. See the darken blending sample.

The color-burn mode works well with colorful top and background layers since it increases saturation in mid-tones. It increases the contrast by tinting pixels in overlapping areas in top and bottom layers more towards the top layer color. Use this blend mode, when you want an effect with more contrast than multiply or darken.

The following screenshots show how the multiply blend mode used for creating a physical map of the world that shows both boundaries and elevation.

Blend mode	Description
darken	Emphasizes the darkest parts of overlapping layers. Colors in the top layer become transparent if they are lighter than the overlapping colors in the background layer, allowing the background layer to show through completely.
multiply	Emphasizes the darkest parts of overlapping layers by multiplying colors of the top layer and the background layer. Midrange colors from top and background layers are mixed together more evenly.
color-burn	Intensifies the dark areas in all layers. It increases the contrast between top and background layers, by tinting colors in overlapping area towards the top color. To do this it inverts colors of the background layer, divides the result by colors of the top layer, then inverts the results.

Contrast blend modes:

The following blend modes create contrast by both lightening the lighter areas and darkening the darker areas in the top layer by using lightening or darkening blend modes to create the blend. The contrast blend modes will lighten the colors lighter than 50% gray ([128,128,128]), and darken the colors darker than 50% gray. 50% gray will be transparent in the top layer. Each mode can create a variety of results depending on the colors of top and background layers being blended together. The overlay blend mode makes its calculations based on the brightness of the colors in the background layer while all of the other contrast blend modes make their calculations based on the brightness of the top layer. Some of these modes are designed to simulate the effect of shining a light through the top layer, effectively projecting upon the layers beneath it.

Contrast blend modes can be used to increase the contrast and saturation to have more vibrant colors and give a punch to your layers. For example, you can duplicate a layer and set overlay blend mode on the top layer to increase the contrast and tones of your layer. You can also add a polygon layer with a white fill symbol over a dark imagery layer and apply soft-light blend mode to increase the brightness in the imagery layer.

The following screenshots show an effect of the overlay blend mode on a GraphicsLayer. The left image shows when the buffer graphics layer has the normal blend mode. As you can see, the gray color for the buffer polygon is blocking the intersecting census tracts. The right image shows when the overlay blend mode is applied to the buffer graphics layer. The overlay blend mode darkens or lightens the gray buffer polygon depending on the colors of the background layer while the census tracts layer is shining through. See this in action.

Normal blend mode	Overlay blend mode

Blend mode	Description
overlay	Uses a combination of multiply and screen modes to darken and lighten colors in the top layer with the background layer always shining through. The result is darker color values in the background layer intensify the top layer, while lighter colors in the background layer wash out overlapping areas in the top layer.
soft-light	Applies a half strength screen mode to lighter areas and half strength multiply mode to darken areas of the top layer. You can think of the soft-light as a softer version of the overlay mode.
hard-light	Multiplies or screens the colors, depending on colors of the top layer. The effect is similar to shining a harsh spotlight on the top layer.
vivid-light	Uses a combination of color-burn or color-dodge by increasing or decreasing the contrast, depending on colors in the top layer.

Component blend modes:

The following blend modes use primary color components, which are hue, saturation and luminosity to blend top and background layers. You can add a feature layer with a simple renderer over any layer and set hue, saturation, color or luminosity blend mode on this layer. With this technique, you create a brand new looking map.

The following screenshots show where the topo layer is blended with world hillshade layer with luminosity blend mode. The result is a drastically different looking map which preserves the brightness of the topo layer while adapting the hue and saturation of the hillshade layer.

Blend mode	Description
hue	Creates an effect with the hue of the top layer and the luminosity and saturation of the background layer.
saturation	Creates an effect with the saturation of the top layer and the hue and luminosity of the background layer. 50% gray with no saturation in the background layer will not produce any change.
luminosity	Creates effect with the luminosity of the top layer and the hue and saturation of the background layer. Can be thought of as the opposite of color blend mode.
color	Creates an effect with the hue and saturation of the top layer and the luminosity of the background layer. Can be thought of as the opposite of luminosity blend mode.

Composite blend modes:

The following blend modes can be used to mask the contents of top, background or both layers.

• Destination modes are used to mask the data of the top layer with the data of the background layer.
• Source modes are used to mask the data of the background layer with the data of the top layer.

The destination-in blend mode can be used to show areas of focus such as earthquakes, animal migration, or point-source pollution by revealing the underlying map, providing a bird’s eye view of the phenomenon. Check out multiple blending and groupLayer blending samples to see composite blend modes in action.

The following screenshots show feature and imagery layers on the left side on their own in the order they are drawn in the view. The imagery layer that contains land cover classification rasters. The feature layer contains 2007 county crops data. The right image shows the result of layer blending where destination-in blendMode is set on the imagery layer. As you can see, the effect is very different from the original layers. The blended result shows areas of cultivated crops only (where both imagery and feature layers overlap).

Blend mode	Description
destination-over	Destination/background layer covers the top layer. The top layer is drawn underneath the destination layer. You'll see the top layer peek through wherever the background layer is transparent or has no data.
destination-atop	Destination/background layer is drawn only where it overlaps the top layer. The top layer is drawn underneath the background layer. You'll see the top layer peek through wherever the background layer is transparent or has no data.
destination-in	Destination/background layer is drawn only where it overlaps with the top layer. Everything else is made transparent.
destination-out	Destination/background layer is drawn where it doesn't overlap the top layer. Everything else is made transparent.
source-atop	Source/top layer is drawn only where it overlaps the background layer. You will see the background layer peek through where the source layer is transparent or has no data.
source-in	Source/top layer is drawn only where it overlaps with the background layer. Everything else is made transparent.
source-out	Source/top layer is drawn where it doesn't overlap the background layer. Everything else is made transparent.
xor	Top and background layers are made transparent where they overlap. Both layers are drawn normal everywhere else.

Invert blend modes:

The following blend modes either invert or cancel out colors depending on colors of the background layer. These blend modes look for variations between top and background layers. For example, you can use difference or exclusion blend modes on two imagery layers of forest covers to visualize how forest covers changed from one year to another.

The invert blend mode can be used to turn any light basemap into a dark basemap to accommodate those who work in low-light conditions. The following screenshots show how setting the invert blend mode set on a feature layer with a simple renderer turns the world terrain basemap into a dark themed basemap in no time.

Blend mode	Description
difference	Subtracts the darker of the overlapping colors from the lighter color. When two pixels with the same value are subtracted, the result is black. Blending with black produces no change. Blending with white inverts the colors. This blending mode is useful for aligning layers with similar content.
exclusion	Similar to the difference blend mode, except that the resulting image is lighter overall. Overlapping areas with lighter color values are lightened, while darker overlapping color values become transparent.
minus	Subtracts colors of the top layer from colors of the background layer making the blend result darker. In the case of negative values, black is displayed.
invert	Inverts the background colors wherever the top and background layers overlap. The invert blend mode inverts the layer similar to a photographic negative.
reflect	This blend mode creates effects as if you added shiny objects or areas of light in the layer. Black pixels in the background layer are ignored as if they were transparent.

Possible Values:"average"|"color-burn"|"color-dodge"|"color"|"darken"|"destination-atop"|"destination-in"|"destination-out"|"destination-over"|"difference"|"exclusion"|"hard-light"|"hue"|"invert"|"lighten"|"lighter"|"luminosity"|"minus"|"multiply"|"normal"|"overlay"|"plus"|"reflect"|"saturation"|"screen"|"soft-light"|"source-atop"|"source-in"|"source-out"|"vivid-light"|"xor"

Default Value:normal

See also

• Layer blending samples

capabilities Capabilitiesreadonly

Describes the layer's supported capabilities.

Example

// Once the layer loads, check if the
// supportsAdd operations is enabled on the layer
featureLayer.when(function(){
  if (featureLayer.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.

customParameters Object

Since: ArcGIS Maps SDK for JavaScript 4.18

A list of custom parameters appended to the URL of all resources fetched by the layer. It's an object with key-value pairs where value is a string. The layer's refresh() method needs to be called if the customParameters are updated at runtime.

Example

// send a custom parameter to your special service
let layer = new MapImageLayer({
  url: serviceUrl,
  customParameters: {
    "key": "my-special-key"
  }
});

datesInUnknownTimezone Booleanreadonly

Since: ArcGIS Maps SDK for JavaScript 4.21

This property is set by the service publisher and indicates that dates should be considered without the local timezone. This applies to both requests and responses.

Known Limitations

• This capability is only available with services published with ArcGIS Enterprise 10.9 or greater.
• Editing is not supported for FeatureLayers if datesInUnknownTimezone is true. The editingEnabled property will be set to false.
• When setting timeExtent in a query, filter or layer, dates must be defined in terms of UTC as illustrated in the code below.
• When using layer.timeInfo.fullTimeExtent in conjunction with TimeSlider, the local timezone offset must be removed. See the code snippet below.

Default Value:false

See also

• ArcGIS REST API - New in 10.9

• What's new in ArcGIS Server 10.9

• Edit map service settings

Examples

// Only download data for the year 2020.
// if the layer supports unknown time zone then create
// the dates in UTC
if (layer.datesInUnknownTimezone) {
  layer.timeExtent = new TimeExtent({
    start: new Date(Date.UTC(2020, 0, 1)),
    end: new Date(Date.UTC(2021, 0, 1))
  });
}
else {
  layer.timeExtent = new TimeExtent({
    start: new Date(2020, 0, 1),
    end: new Date(2021, 0, 1)
  });
}

// set up the timeslider for a service with an unknown timezone
if (layer.datesInUnknownTimezone) {
  const timeSlider = new TimeSlider({
    view: view,
    container: "timeSliderDiv",
    timeVisible: true,
  });
  view.ui.add(timeSlider, "bottom-left");

  view.whenLayerView(layer).then((layerView) => {
   // get the layer's fullTimeExtent and remove the local
   // time zone offset
    const timExtent = new TimeExtent({
      start: removeLocalOffset(layer.timeInfo.fullTimeExtent.start),
      end: removeLocalOffset(layer.timeInfo.fullTimeExtent.end)
    });

    timeSlider.fullTimeExtent = timExtent;
    timeSlider.stops = {
      interval: layer.timeInfo.interval;
    };
  });
}

// Remove the local time zone offset from dates
function removeLocalOffset(localTime) {
  return new Date(
    localTime.getUTCFullYear(),
    localTime.getUTCMonth(),
    localTime.getUTCDate(),
    localTime.getUTCHours(),
    localTime.getUTCMinutes(),
    localTime.getUTCSeconds(),
    localTime.getUTCMilliseconds()
  );
}

declaredClass Stringreadonly inherited

Since: ArcGIS Maps SDK for JavaScript 4.7

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. Setting a definition expression is useful when the dataset is large and you don't want to bring all features to the client for analysis. 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 trees with scientific name Ulmus pumila
const layer = new FeatureLayer({
  url: "https://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/Landscape_Trees/FeatureServer/0",
  definitionExpression: "Sci_Name = 'Ulmus pumila'"
});

// Set the definition expression directly on layer instance to only display trees taller than 50ft
layer.definitionExpression = "HEIGHT > 50";

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.

dynamicDataSource DynamicMapLayer|DynamicDataLayer

Since: ArcGIS Maps SDK for JavaScript 4.7

An object that allows you to create a dynamic layer with data either from map service sublayers or data from a registered workspace. See DynamicMapLayer for creating dynamic layers from map service layers for on the fly rendering, labeling, and filtering (definition expressions). To create dynamic layers from other sources in registered workspaces such as tables and table joins, see DynamicDataLayer.

If you already have a Sublayer instance, you can call the createFeatureLayer() method on the Sublayer to construct the layer for you.

This only applies to map services with dynamic layers enabled.

Known Limitations

FeatureLayers with a dynamicDataSource cannot be persisted to web maps, web scenes, and portal items.

See also

• Sublayer.source
• Sublayer.createFeatureLayer()

Example

const layer = new FeatureLayer({
  url: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/AGP/Census/MapServer",
  title: "United States Population",
  popupTemplate: {
    title: "{states.STATE_NAME}",
    content: "{expression/per_ancestry}% of the {states.POP2007} people in {states.STATE_NAME} have "
      + "Norwegian ancestry.",
    expressionInfos: [{
      name: "per_ancestry",
      expression: "Round( ( $feature['ancestry.norwegian'] / $feature['states.POP2007'] ) * 100, 1)"
    }],
    fieldInfos: [{
      fieldName: "states.POP2007",
      format: {
        digitSeparator: true,
        places: 0
      }
    }]
  },
  dynamicDataSource: {
    type: "data-layer",
    dataSource: {
      type: "join-table",
      leftTableSource: {
        type: "map-layer",
        mapLayerId: 3
      },
      rightTableSource: {
        type: "data-layer",
        dataSource: {
          type: "table",
          workspaceId: "CensusFileGDBWorkspaceID",
          dataSourceName: "ancestry"
        }
      },
      leftTableKey: "STATE_NAME",
      rightTableKey: "State",
      joinType: "left-outer-join"
    }
  }
});

editFieldsInfo EditFieldsInforeadonly

The editor tracking fields, which record who adds or edits the data through the feature service and when edits are made.

editingEnabled Boolean

Since: ArcGIS Maps SDK for JavaScript 4.18

Determines if the layer is editable.

Default Value:true

See also

• applyEdits

editingInfo EditingInforeadonly

Specifies information about editing.

effect Effectautocast

Since: ArcGIS Maps SDK for JavaScript 4.18

Effect provides various filter functions that can be performed on the layer to achieve different visual effects similar to how image filters work. This powerful capability allows you to apply css filter-like functions to layers to create custom visual effects to enhance the cartographic quality of your maps. This is done by applying the desired effect to the layer's effect property as a string or an array of objects to set scale dependent effects.

Notes

• Set featureEffect property if different effects need to be applied features that meet or fail a specified filter.
• If all of the following four properties are applied, then they will be applied in this order: featureEffect, effect, opacity and blendMode.

Known Limitations

• The effect is not supported in 3D SceneViews.
• The effect cannot be applied to a layer with a heatmap renderer.
• The effect is not supported in layers with featureReduction of type cluster enabled.
• See print for known printing limitations.

Default Value:null

See also

• featureEffect

• More information on how to set effect

• Layer and layer view effect samples

Examples

// the following effect will be applied to the layer at all scales
// brightness will be applied first, then hue-rotate followed by contrast
// changing order of the effects will change the final result
layer.effect = "brightness(5) hue-rotate(270deg) contrast(200%)";

// set a scale dependent bloom effect on the layer
layer.effect = [
  {
    scale: 36978595,
    value: "drop-shadow(3px, 3px, 4px)"
  },
  {
    scale: 18489297,
    value: "drop-shadow(2px, 2px, 3px)"
  },
  {
    scale: 4622324,
    value: "drop-shadow(1px, 1px, 2px)"
  }
];

effectiveCapabilities Capabilitiesreadonly

Since: ArcGIS Maps SDK for JavaScript 4.26

Describes effective capabilities of the layer taking in to consideration privileges of the currently signed-in user.

effectiveEditingEnabled Booleanreadonly

Since: ArcGIS Maps SDK for JavaScript 4.26

Indicates whether the layer is editable taking in to consideration privileges of the currently signed-in user.

elevationInfo Object

Specifies how features 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 feature is placed with respect to the terrain surface or 3D objects in the scene. If the geometry consists of multiple points (e.g. lines or polygons), the elevation is evaluated separately for each point. See the table below for a list of possible values. Mode Description on-the-ground Features are aligned to the Ground. If the scene contains an IntegratedMeshLayer, then features are aligned to the IntegratedMeshLayer. If features have z-values, then the z-values are ignored in this mode. Features with 2D symbols are draped on the Ground or IntegratedMeshLayer. This is the default mode for layers without z-values containing Polyline, Polygon features or Point features rendered with ObjectSymbol3DLayer. absolute-height Features are placed at an absolute elevation (z-value) above sea level. This z-value is determined by the geometry's z-value (if present). If featureExpressionInfo is defined, the result of the expression is used instead of the geometry’s z-value. This mode doesn't take the elevation of the Ground or any other layers into account. This is the default value of features with any geometry type where hasZ is true. relative-to-ground Features are placed at an elevation relative to the Ground or IntegratedMeshLayer. The feature's elevation is determined by summing up the elevation of the Ground or IntegratedMeshLayer and the geometry's z-value (if present). If featureExpressionInfo is defined, the result of the expression is used instead of the geometry’s z-value. If the geometries don't have z-values, relative-to-ground is the default value for Point geometries rendered with IconSymbol3DLayers. relative-to-scene Features are aligned to extruded polygons, 3D Object SceneLayers or BuildingSceneLayers, depending on which one has higher elevation. If the feature is not directly above a building or any other feature, it is aligned to the elevation of the Ground or the IntegratedMeshLayer. If present, the geometry's z-value is added to the elevation. If featureExpressionInfo is defined, the result of the expression is used instead of the geometry’s z-value. 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 feature. If unit is not defined, the offset is in meters. When mode = "on-the-ground", this property has no effect.

featureExpressionInfo Object optional Defines how to override a feature's Z-value based on its attributes. Specification expression String optional An Arcade expression following the specification defined by the Arcade Feature Z Profile. Expressions may reference field values using the $feature profile variable and must return a number representing 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"

See also

• Arcade Feature Z Profile

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.

Notes

• Set the effect property if the effect needs to be applied to the entire layer.
• If the featureEffect is set on the layer, it will be inherited by layerView.featureEffect unless the developer overrides it on the layer view. The layerView.featureEffect will take precedence over layer.featureEffect if both properties are set.
• If all of the following four properties are applied, then they will be applied in this order: featureEffect, effect, opacity and blendMode.

Known Limitations

• FeatureEffect is not supported in the following scenarios:
  • In 3D SceneViews
  • In a layer rendered with a HeatmapRenderer
  • When FeatureReductionCluster is enabled
  • See print for known printing limitations.

See also

• Sample - Apply effects to features

• Sample - Apply drop-shadow effect to a layerView

• effect

Examples

// gray out features that fall outside of the 3 mile buffer of the mouse's location
// by setting feature effect on excluded features
layer.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'"
});
layer.featureEffect = new FeatureEffect({
  filter: featureFilter,
  includedEffect: "drop-shadow(3px, 3px, 3px, black)",
  excludedEffect: "blur(1px) brightness(65%)"
});

featureReduction FeatureReductionBinning|FeatureReductionCluster|FeatureReductionSelectionautocast

Since: ArcGIS Maps SDK for JavaScript 4.4

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 three types of feature reduction: selection, cluster, and binning.

• 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 groups points in a MapView into clusters defined in screen space. Each cluster is a point whose size is proportional to the number of features within the cluster. This has been available since version 4.14.
• Binning spatially groups points in a MapView into bins clearly defining the area aggregating features in map space. This has been available since version 4.24.

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"
};

// Aggregates features to bins
layer.featureReduction = {
  type: "binning",
  renderer: {
    type: "simple",  // autocasts as new SimpleRenderer()
    symbol: {
      type: "simple-fill",  // autocasts as new SimpleFillSymbol()
      outline: {  // autocasts as new SimpleLineSymbol()
        width: 0.5,
        color: "white"
      }
    },
    visualVariables: [{
      type: "color",
      field: "aggregateCount",
      stops: [
        { value: 1, color: "white" },
        { value: 1000, color: "blue" }
      ]
    }]
  },
  popupTemplate: {
    content: "This bin contains <b>{aggregateCount}</b> features.",
    fieldInfos: [{
      fieldName: "aggregateCount",
      format: {
        digitSeparator: true,
        places: 0
      }
    }]
  }
};

fields Field[]autocast

Autocasts from Object[]

An array of fields in the layer. Each field represents an attribute that may contain a value for each feature in the layer. For example, a field named POP_2015, stores information about total population as a numeric value for each feature; this value represents the total number of people living within the geographic bounds of the feature.

When creating a FeatureLayer from client-side features, this property should be set in the constructor along with the source property. The objectId field also must be set either in this array or in the objectIdField property.

See also

• source

• objectIdField

• Add an array of client-side features

Example

// define each field's schema
const 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"
 })
];

// See the sample snippet for the source and renderer properties
const layer = new FeatureLayer({
  // geometryType and spatialReference are inferred
  // from the input source features
  source: features,
  // Object ID field is inferred from the fields array
  fields: fields,
  renderer: renderer
});

fieldsIndex FieldsIndexreadonly

Since: ArcGIS Maps SDK 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
}

floorInfo LayerFloorInfoautocast

Since: ArcGIS Maps SDK for JavaScript 4.19

When a feature layer is configured as floor-aware, it has a floorInfo property defined. A floor-aware layer is a layer that contains indoor GIS data representing features that can be located on a specific floor of a building.

formTemplate FormTemplateautocast

Since: ArcGIS Maps SDK for JavaScript 4.16

The template used in an associated layer's FeatureForm. All of the properties and field configurations set on the layer's FeatureForm are handled via the FormTemplate.

See also

• Sample - Update Feature Attributes

Example

// Create the Field Elements to pass into the template
const fieldElement1 = new FieldElement({
  fieldName: "firstname",
  label: "First name",
  description: "First name of emergency contact"
});

const fieldElement2 = new FieldElement({
  fieldName: "lastname",
  label: "Last name",
  description: "Last name of emergency contact"
});

// Create the form's template
const formTemplate = new FormTemplate({
  title: "Emergency information",
  description: "In case of emergency, update any additional information needed",
  elements: [fieldElement1, fieldElement2] // pass in array of field elements from above
});

// Pass the template to the layer
featureLayer.formTemplate = formTemplate;

// Pass the layer to the FeatureForm
const form = new FeatureForm({
  container: "form", // html div referencing the form
  layer: featureLayer
});

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;
});

gdbVersion String

The version of the geodatabase of the feature service data. Read the Overview of versioning topic for more details about this capability.

geometryFieldsInfo GeometryFieldsInforeadonly

Since: ArcGIS Maps SDK for JavaScript 4.19

Provides information on the system maintained area and length fields along with their respective units.

See also

• ArcGIS REST API documentation

geometryType String

The geometry type of features in the layer. All features must be of the same type. This property is read-only when the layer is created from a url.

When creating a FeatureLayer from client-side features, this property is inferred by the geometryType of the features provided in the layer's source property. If the layer's source is an empty array at the time of initialization, this property must be set.

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

See also

• Add an array of client-side features

hasM Boolean

Indicates whether the client-side features in the layer have M (measurement) values. Use the supportsM property in the FeatureLayer's capabilities.data object to verify if M values are supported on feature service features.

Default Value:undefined

hasZ Boolean

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 FeatureLayer's capabilities.data object to verify if Z values are supported on feature service features.

Default Value:undefined

historicMoment Dateautocast

The historic moment to query. If historicMoment is not specified, the query will apply to the current features.

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.

isTable Booleanreadonly

Since: ArcGIS Maps SDK for JavaScript 4.11

Returns true if the layer is loaded from a non-spatial table in a service. Non-spatial tables do not have a spatial column that represent geographic features.

Default Value:false

See also

• Map.tables
• WebMap.tables
• Map.allTables
• WebMap.allTables

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).

See the Labeling guide page for more information and known limitations.

Known Limitations

3D SceneViews only support displaying one LabelClass per feature.

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"
  }
});

featureLayer.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

3D SceneViews only support displaying one LabelClass per feature.

Default Value:true

layerId Number

The layer ID, or layer index, of a Feature Service layer. This is particularly useful when loading a single FeatureLayer with the portalItem property from a service containing multiple layers. You can specify this value in one of two scenarios:

• When loading the layer via the portalItem property.
• When pointing the layer url directly to the Feature Service.

If a layerId is not specified in either of the above scenarios, then the first layer in the service (layerId = 0) is selected.

Examples

// loads the third layer in the given Portal Item
const layer = new FeatureLayer({
  portalItem: {
    id: "8d26f04f31f642b6828b7023b84c2188"
  },
  layerId: 2
});

// If not specified, the first layer (layerId: 0) will be returned
const layer = new FeatureLayer({
  portalItem: {
    id: "8d26f04f31f642b6828b7023b84c2188"
  }
});

// Can also be used if URL points to service and not layer
const layer = new FeatureLayer({
  // Notice that the url doesn't end with /2
  url: "http://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/MonterreyBayCanyon_WFL/FeatureServer",
  layerId: 2
});

// This code returns the same layer as the previous snippet
const layer = new FeatureLayer({
  // The layer id is specified in the URL
  url: "http://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/MonterreyBayCanyon_WFL/FeatureServer/2",
});

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. This property is required when constructing a FeatureLayer from a collection of client-side features. If not specified, it will be inferred from the fields array.

See also

• fields

• Add an array of client-side features

Example

// See the sample snippet for the source and fields properties
const layer = new FeatureLayer({
  source: features,
  fields: fields,
  objectIdField: "ObjectID",  // field name of the Object IDs
  geometryType: "point",
  renderer: <renderer>
});

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;

orderBy Object[]

Since: ArcGIS Maps SDK for JavaScript 4.21

Determines the order in which features are drawn in the view. You can sort features by a field value or the value returned from an Arcade expression in ascending or descending order.

When null (default), features are drawn in the order they are returned from the service or client.

Known Limitations

• This property only controls feature drawing order in MapView. Configuring feature drawing order in SceneView is not supported.
• This property does not control the drawing order of clusters. It only applies to individual features.
• Feature drawing order configurations defined with Arcade expressions cannot be saved to webmaps.
• Currently, you can only sort features by one field or expression.

Properties

field String optional The number or date field whose values will be used to sort features.

valueExpression String optional An Arcade expression following the specification defined by the Arcade Feature Z Profile. Expressions may reference field values using the $feature profile variable and must return a number or a date representing the z-value used to sort features.

order String optional Default Value:ascending The sort order. If ascending, then features with smaller data values (they usually have smaller symbols in size visualizations) will be drawn on top of features with larger data values. If descending, then features with larger data values (usually larger symbols in size visualizations) will be drawn on top of features with smaller data values. If date values are used, then ascending means features with older values will be drawn on top of features with more recent dates. A descending order for dates indicates features with more recent values will be drawn on top of features with older values. Possible Values:"ascending"|"descending"

Default Value:null

See also

• Arcade Feature Z Profile

Examples

// Features with smaller population values will
// be rendered on top of larger features.
layer.orderBy = [{
  field: "POPULATION"
}];

// Features with larger population values will
// be rendered on top of smaller features.
layer.orderBy = [{
  field: "POPULATION",
  order: "descending"
}];

// Orders features by date in descending order.
// The most recent features will be rendered
// on top of older features.
layer.orderBy = [{
  field: "Alarm_Date",
  order: "descending"
}];

// Orders features by storm warning duration in descending order.
// Warnings with longer durations
// be rendered on top of warnings with shorter durations.
layer.orderBy = [{
  valueExpression: "DateDiff($feature.Watch_End, $feature.Watch_Start, 'hours' )",
  order: "descending"
}];

// Orders features by data values used in a size visual variable
const sizeVariable = layer.renderer.visualVariables.find( vv => vv.type === "size");
const { field, valueExpression } = sizeVariable;
layer.orderBy = [{
  field,
  valueExpression,
  order: "ascending"
}];

outFields String[]

An array of field names from the service to include with each feature. To fetch the values from all fields in the layer, use ["*"]. Fields specified in outFields will be requested alongside with required fields for rendering, labeling and setting the elevation info for the layer. The required fields and outFields are used to populate FeatureLayerView.availableFields. Set this property to include the fields that will be used for client-side queries if the fields are not part of required fields used for rendering.

Default Value:null

See also

• FeatureLayerView.availableFields
• fieldUtils

Examples

// Includes all fields from the service in the layer
fl.outFields = ["*"];

// Get the specified fields from the service in the layer
// These fields will be added to FeatureLayerView.availableFields
// along with rendering and labeling fields. Use these fields
// for client-side filtering and querying.
fl.outFields = ["NAME", "POP_2010", "FIPS", "AREA"];

// set the outFields for the layer coming from webmap
webmap.when(function () {
  layer = webmap.layers.getItemAt(1);
  layer.outFields = ["*"];
});

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

portalItem PortalItem

The portal item from which the layer is loaded. If the portal item references a Feature Service or Scene Service, then you can specify a single layer to load with the layerId property.

Beginning with version 4.17, it is possible to load tables from feature service items hosted in ArcGIS Online and ArcGIS Enterprise. This only applies to feature layers, and will successfully load if FeatureLayer.isTable returns true.

Examples

// While this example uses FeatureLayer, this same pattern can be
// used for other layers that may be loaded from portalItem ids.
const layer = new FeatureLayer({
  portalItem: {  // autocasts as new PortalItem()
    id: "caa9bd9da1f4487cb4989824053bb847"
  }  // the first layer in the service is returned
});

// Set hostname when using an on-premise portal (default is ArcGIS Online)
// esriConfig.portalUrl = "http://myHostName.esri.com/arcgis";

// While this example uses FeatureLayer, this same pattern can be
// used for SceneLayers.
const layer = new FeatureLayer({
  portalItem: {  // autocasts as new PortalItem()
    id: "8d26f04f31f642b6828b7023b84c2188"
  },
  // loads the third item in the given feature service
  layerId: 2
});

// Initialize GeoJSONLayer by referencing a portalItem id pointing to geojson file.
const layer = new GeoJSONLayer({
  portalItem: new PortalItem({
    id: "81e769cd7031482797e1b0768f23c7e1",
    // optionally define the portal, of the item.
    // if not specified, the default portal defined is used.
    // see https://developers.arcgis.com/javascript/latest/api-reference/esri-config.html#portalUrl
    portal: new Portal({
      url: "https://jsapi.maps.arcgis.com/"
    })
  }
});

// This snippet loads a table hosted in ArcGIS Online.
const table = new FeatureLayer({
  portalItem: { // autocasts as esri/portal/PortalItem
    id: "123f4410054b43d7a0bacc1533ceb8dc"
  }
});

// Before adding the table to the map, it must first be loaded and confirm it is the right type.
table.load().then(function() {
  if (table.isTable) {
    map.tables.add(table);
  }
});

publishingInfo PublishingInforeadonly

Since: ArcGIS Maps SDK for JavaScript 4.25

Checks layer's publishing status while the layer is being published to the portal. This stops when the status has been determined or when the layer is destroyed. The layer is automatically refreshed when the layer is done publishing. This is valid only for ArcGIS Online hosted feature services.

Example

// Log the current publishing status after each checks.
when(
  () => !layer.publishingInfo.updating,
  (status) => {
    switch (layer.publishingInfo.status) {
      case "unknown":
        console.log("The layer's publishing status is unknown at this point");
        break;
      case "unavailable":
        console.log("The layer doesn't provide publishing information");
        break;
      case "publishing":
        console.log("Layer is publishing");
        break;
      case "published":
        console.log("Layer is published at", layer.url);
        break;
    }
  },
  { initial: true }
);

refreshInterval Number

Since: ArcGIS Maps SDK for JavaScript 4.6

Refresh interval of the layer in minutes. Value of 0 indicates no refresh. At each refresh interval, the data is only updated if the lastEditDate in the layer's metadata is different from the lastEditDate field. If the lastEditDate metadata info is not available, the FeatureLayer refreshes unconditionally.

Default Value:0

See also

• refresh()

• refresh event

Example

// the layer will be refreshed every 6 seconds.
layer.refreshInterval = 0.1;

relationships Relationship[]readonly

Since: ArcGIS Maps SDK for JavaScript 4.9

Array of relationships set up for the layer. Each object in the array describes the layer's relationship with another layer or table.

See also

• queryRelatedFeatures

Example

// print out layer's relationship length and each relationship info to console
layer.when(function () {
  console.log("layer relationships", layer.relationships.length);

  layer.relationships.forEach(function (relationship) {
    console.log("relationship id:", relationship.id)
    console.log("relationship cardinality:", relationship.cardinality)
    console.log("relationship key field:", relationship.keyField)
    console.log("relationship name:", relationship.name)
    console.log("relationship relatedTableId:", relationship.relatedTableId)
  });
});

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.

However, when creating a FeatureLayer from client-side features, this property must be specified in the layer's constructor along with the source, fields, objectIdField properties.

See also

• Styles and data visualization

Example

// all features in the layer will be visualized with
// a 6pt black marker symbol and a thin, white outline
layer.renderer = {
  type: "simple",  // autocasts as new SimpleRenderer()
  symbol: {
    type: "simple-marker",  // autocasts as new SimpleMarkerSymbol()
    size: 6,
    color: "black",
    outline: {  // autocasts as new SimpleLineSymbol()
      width: 0.5,
      color: "white"
    }
  }
};

returnM Boolean

When true, indicates that M values will be returned. When false, indicates that M values will never be returned. The layer view determines whether to include M values in feature queries when the property value is undefined.

Default Value:undefined

returnZ Boolean

When true, indicates that z-values will always be returned. When false, indicates that z-values will never be returned. The layer view determines whether to include z-values in feature queries when the property value is undefined.

Default Value:undefined

screenSizePerspectiveEnabled Boolean

Since: ArcGIS Maps SDK for JavaScript 4.4

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

See also

• Sample: Point styles for cities

serviceDefinitionExpression Stringreadonly

Since: ArcGIS Maps SDK for JavaScript 4.16

The service definition expression limits the features available for display and query. You can define additional filters on the layer in addition to the service definition expression by setting layer's definitionExpression. For example, if the service definition expression is set to display data where "STATE_NAME = 'California'" you could use definitionExpression to only display a subset of the features in California, for example using "COUNTY='San Diego'".

See also

• Set hosted feature layer view definition

source Collection<Graphic>autocast

Autocasts from Object[]

A collection of Graphic objects used to create a FeatureLayer. The geometry of each feature all must have a matching geometryType. This property must be set when creating a FeatureLayer from client-side features. When creating a FeatureLayer from client-side features, the objectId field must be set either in the fields array or via objectIdField.

The spatialReference and geometryType properties are determined based on the features provided to this property. If the source is an empty array at the time of layer initialization, then geometryType must be set.

The source is not updated after the FeatureLayer is initialized. Use applyEdits() method to add, remove, and update features from a client-side feature layer at runtime. Once applyEdits() resolves successfully, use queryFeatures() to return updated features.

See also

• Add an array of client-side features

• Sample - Create a FeatureLayer with client-side graphics

• Sample - Add or remove graphics from a FeatureLayer

• Sample - Add 100,000 features to feature collection

Example

let features = [
 {
   geometry: {
     type: "point",
     x: -100,
     y: 38
   },
   attributes: {
     ObjectID: 1,
     DepArpt: "KATL",
     MsgTime: Date.now(),
     FltId: "UAL1"
   }
 },
 ...
];

// geometryType and spatialReference of the layer
// will be inferred from the first feature in the array
// if it has a geometry.
let layer = new FeatureLayer({
  source: features,  // autocast as a Collection of new Graphic()
  objectIdField: "ObjectID"
});

sourceJSON Object

Since: ArcGIS Maps SDK for JavaScript 4.13

The feature service's metadata JSON exposed by the ArcGIS REST API. While most commonly used properties are exposed on the FeatureLayer class directly, this property gives access to all information returned by the feature service. This property is useful if working in an application built using an older version of the API which requires access to feature service properties from a more recent version.

spatialReference SpatialReferenceautocast

The spatial reference of the layer. When creating the layer from a url, the spatial reference is read from the service.

When creating a FeatureLayer from client-side features, this property is inferred from the geometries of the features provided in the source property.

templates FeatureTemplate[]

Since: ArcGIS Maps SDK for JavaScript 4.4

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

timeExtent TimeExtentautocast

Since: ArcGIS Maps SDK 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, and both layer and view time extents are set, then features that fall within the intersection of the view and layer time extents will be displayed. For example, if the layer's time extent is set to display features between 1970 and 1975 and the view has a time extent set to 1972-1980, the effective time on the feature layer will be 1972-1975.

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
});

// timeExtent is set on the layer and the view
// In this case, the layer will display features that fall
// within the intersection of view and layer time extents
// features within Jan 1, 1976 - Jan 1, 1981 will be displayed
const view = new MapView({
  timeExtent: {
    start: new Date(1976, 0, 1),
    end: new Date(2002, 0, 1)
  }
});
const layer = new FeatureLayer({
  url: myUrl,
  timeExtent: {
    start: new Date(1974, 0, 1),
    end: new Date(1981, 0, 1)
  }
});

timeInfo TimeInfoautocast

Since: ArcGIS Maps SDK for JavaScript 4.11

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 CSVLayer, GeoJSONLayer 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
  // The date values must be in milliseconds number from the UNIX epoch specified in UTC.
  timeInfo: {
    startField: "time"
  }
});

timeOffset TimeIntervalautocast

Since: ArcGIS Maps SDK 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).
let 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.

When loading a layer by service url, the title is derived from the service name. If the service has several layers, then the title of each layer will be the concatenation of the service name and the layer name. When the layer is loaded from a portal item, the title of the portal item will be used instead. Finally, if a layer is loaded as part of a webmap or a webscene, then the title of the layer as stored in the webmap/webscene will be used.

type Stringreadonly

For FeatureLayer the type is always "feature".

typeIdField String

Since: ArcGIS Maps SDK for JavaScript 4.4

The name of the field holding the type ID or subtypes for the features. See ArcGIS Pro subtypes document.

types FeatureType[]

Since: ArcGIS Maps SDK for JavaScript 4.4

An array of subtypes defined in the feature service exposed by ArcGIS REST API. Each item includes information about the type, such as the type ID, name, and definition expression.

url String

The absolute URL of the REST endpoint of the layer, non-spatial table or service. The URL may either point to a resource on ArcGIS Enterprise or ArcGIS Online.

If the url points directly to a service, then the layer must be specified in the layerId property. If no layerId is given, then the first layer in the service will be loaded.

Examples

// Hosted Feature Service on ArcGIS Online
layer.url = "http://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/origins/FeatureServer/0";

// Layer from Map Service on ArcGIS Server
layer.url = "http://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer/2";

// Can also be used if URL points to service and not layer
const layer = new FeatureLayer({
  // Notice that the url doesn't end with /2
  url: "http://services.arcgis.com/V6ZHFr6zdgNZuVG0/arcgis/rest/services/MonterreyBayCanyon_WFL/FeatureServer",
  layerId: 2
});

// Non-spatial table in San Francisco incidents service.
const table = new FeatureLayer({
  url: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/SF311/FeatureServer/1"
});
// table must be loaded so it can be used in the app.
table.load().then(function() {
  // table is loaded. ready to be queried.
});

useViewTime Boolean

Since: ArcGIS Maps SDK for JavaScript 4.14

Determines if the layer will update its temporal data based on the view's timeExtent. When false, the layer will display its temporal data based on the layer's timeExtent, regardless of changes to the view. If both view and layer time extents are set while this property is true, then the features that fall within the intersection of the view and layer time extents will be displayed. For example, if a layer's time extent is set to display features between 1970 and 1975 and the view has a time extent set to 1972-1980, the effective time on the feature layer will be 1972-1975.

Default Value:true

Example

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

version Numberreadonly

The version of ArcGIS Server in which the layer is published.

Example

// Prints the version number to the console - e.g. 10.2, 10.3, 10.41, etc.
console.log(layer.version);

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

addAttachment(feature, attachment){Promise<FeatureEditResult>}

Since: ArcGIS Maps SDK for JavaScript 4.9

Adds an attachment to a feature. This operation is available only if the layer's capabilities.data.supportsAttachment is set to true.

Parameters

feature Graphic Feature to which the attachment is to be added.

attachment HTMLFormElement|FormData HTML form that contains a file upload field pointing to the file to be added as an attachment.

Returns

Type	Description
Promise<FeatureEditResult>	When resolved, a FeatureEditResult object is returned. FeatureEditResult indicates whether or not the edit was successful. If successful, the objectId of the result is the Id of the new attachment. If unsuccessful, it also includes an error name and error message.

See also

• capabilities.data.supportsAttachment

Example

view.when(function () {
  view.on("click", function (event) {

    view.hitTest(event).then(function (response) {
      const feature = response.results[0].graphic;

      // The form is defined as below in the html.
      // For enterprise services:
      // 1. File input name must be "attachment"
      // <form id="attachmentForm">
      //   Select a file: <input type="file" name="attachment">
      // </form>
      const attachmentForm = document.getElementById("attachmentForm");
      const formData = new FormData(attachmentForm);

      // For enterprise services - add input with name:f and value:json
      formData.append("f","json");
      const form = new FormData();
      form.set("attachment", file);
      form.append("f","json")
      let form = document.getElementById("myForm");

      // Add an attachment to the clicked feature.
      // The attachment is taken from the form.
      layer.addAttachment(feature, form).then(function (result) {
        console.log("attachment added: ", result);
      })
      .catch(function (err) {
        console.log("attachment adding failed: ", err);
      });
    });
  });
});

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.

applyEdits(edits, options){Promise<EditsResult>}

Applies edits to features in a layer. New features can be created and existing features can be updated or deleted. Feature geometries and/or attributes may be modified. Only applicable to layers in a feature service and client-side features set through the FeatureLayer's source property. Attachments can also be added, updated or deleted.

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

When calling the applyEdits method on a service that does not have vertical coordinate system information, the z-values of the geometries in the edits object will automatically be converted to match the spatial reference of the layer. Example: The service has a horizontal spatial reference with feet units, and applyEdits() is called with z-values based on meter units, then the method will automatically convert the z values from meter to feet units.

As of version 4.17, using applyEdits to add geometries with z-values to a FeatureLayer with hasZ: false no longer silently drops the z-value and now throws an error.

Parameters

Specification

edits Object Object containing features and attachments 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[]|Collection<Graphic>|Object[] optional An array or a collection of features, or an array of objects with objectId or globalId of each feature 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 value set for objectId or globalId property. addAttachments AttachmentEdit[] optional An array of attachments to be added. Applies only when the options.globalIdUsed parameter is set to true. User must provide globalIds for all attachments to be added. updateAttachments AttachmentEdit[] optional An array of attachments to be updated. Applies only when the options.globalIdUsed parameter is set to true. User must provide globalIds for all attachments to be updated. deleteAttachments String[] optional An array of globalIds for attachments to be deleted. Applies only when the options.globalIdUsed parameter is set to true.

options Object optional Additional edit options to specify when editing features or attachments. Specification gdbVersion String optional The geodatabase version to apply the edits. This parameter applies only if the capabilities.data.isVersioned property of the layer is true. If the gdbVersion parameter is not specified, edits are made to the published map’s version. returnEditMoment Boolean optional Indicates whether the edit results should return the time edits were applied. If true, the feature service will return the time edits were applied in the edit result's editMoment property. Only applicable with ArcGIS Server services only. This option was added at the version 4.20. returnServiceEditsOption String optional If set to original-and-current-features, the EditedFeatureResult parameter will be included in the applyEdits response. It contains all edited features participating in composite relationships in a database as result of editing a feature. Note that even for deletions, the geometry and attributes of the deleted feature are returned. The original-and-current-features option is only valid when rollbackOnFailureEnabled is true. The default value is none, which will not include the EditedFeatureResult parameter in the response. This is only applicable with ArcGIS Server services only. This option was added at the version 4.20. Possible Values:"none"|"original-and-current-features" rollbackOnFailureEnabled Boolean optional Indicates whether the edits should be applied only if all submitted edits succeed. If false, the server will apply the edits that succeed even if some of the submitted edits fail. If true, the server will apply the edits only if all edits succeed. The layer's capabilities.editing.supportsRollbackOnFailure property must be true if using this parameter. If supportsRollbackOnFailure is false for a layer, then rollbackOnFailureEnabled will always be true, regardless of how the parameter is set. globalIdUsed Boolean optional Indicates whether the edits can be applied using globalIds of features or attachments. This parameter applies only if the layer's capabilities.editing.supportsGlobalId property is true. When false, globalIds submitted with the features are ignored and the service assigns new globalIds to the new features. When true, the globalIds must be submitted with the new features. When updating existing features, if the globalIdUsed is false, the objectIds of the features to be updated must be provided. If the globalIdUsed is true, globalIds of features to be updated must be provided. When deleting existing features, set this property to false as deletes operation only accepts objectIds at the current version of the API. When adding, updating or deleting attachments, globalIdUsed parameter must be set to true and the attachment globalId must be set. For new attachments, the user must provide globalIds. In order for an attachment to be updated or deleted, clients must include its globalId. Attachments are not supported in an edit payload when globalIdUsed is false. // add an image attachments to features function addAttachment(selectedFeature) { const blob = new Blob(byteArrays, { type: "image/png" }); addAttachments.push({ feature: selectedFeature, attachment: { globalId: "8c4d6085-a33c-42a0-8e11-21e9528bca0d", name: "brokenLight", data: blob } }); const edits = { addAttachments: addAttachments }; const options = { // globalIdUsed has to be true when adding, updating or deleting attachments globalIdUsed: true, rollbackOnFailureEnabled: true }; featureLayer.applyEdits(edits, options).then(function(results) { console.log("edits added: ", results); }); }

Returns

Type	Description
Promise<EditsResult>	When resolved, an EditsResult object is returned.

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 deleteFeatures = [
    { objectId: 467 },
    { objectId: 500 }
  ];

  // or specify globalIds of features to be deleted
  // const deleteFeature = [
  //  { globalId: "18633204-1801-4d35-a73a-174563608ad9" }
  // ];

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

cancelLoad()inherited

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

clone(){this}

Creates a deep clone of this object. Any properties that store values by reference will be assigned copies of the referenced values on the cloned instance.

Returns

Type	Description
this	A deep clone of the class instance that invoked this method.

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}

Since: ArcGIS Maps SDK for JavaScript 4.11

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

Parameter

options CreatePopupTemplateOptions optional Options for creating the popup template.

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, gdbVersion, and historicMoment. It will return Z and M values based on the layer's data capabilities. It sets the query parameter's outFields property to ["*"]. The results will include geometries of features and values for all available fields for client-side queries or all fields in the layer for server side queries.

Returns

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

See also

• Sample - Query features from a FeatureLayer

Examples

// this snippet shows the query parameter object that is returned
// from FeatureLayer.createQuery().
const queryParams = new Query();
const dataCapabilities = layer.get<DataCapabilities>("capabilities.data");

queryParams.gdbVersion = layer.gdbVersion;
queryParams.historicMoment = layer.historicMoment;
queryParams.returnGeometry = true;

if (dataCapabilities) {
  if (dataCapabilities.supportsZ && layer.returnZ != null) {
    queryParams.returnZ = layer.returnZ;
  }

  if (dataCapabilities.supportsM && layer.returnM != null) {
    queryParams.returnM = layer.returnM;
  }
}

queryParams.outFields = ["*"];
queryParams.where = layer.definitionExpression || "1=1";
queryParams.multipatchOption = layer.geometryType === "multipatch" ? "xyFootprint" : null;

// 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);
});

deleteAttachments(feature, attachmentIds){Promise<FeatureEditResult[]>}

Since: ArcGIS Maps SDK for JavaScript 4.9

Deletes attachments from a feature. This operation is available only if the layer's capabilities.data.supportsAttachment is set to true.

Parameters

feature Graphic Feature containing attachments to be deleted.

attachmentIds Number[] Ids of the attachments to be deleted.

Returns

Type	Description
Promise<FeatureEditResult[]>	When resolved, an array of FeatureEditResults is returned. FeatureEditResult indicates whether or not the edit was successful. If successful, the objectId of the result is the Id of the new attachment. If unsuccessful, it also includes an error name and error message.

See also

• capabilities.data.supportsAttachment

destroy()inherited

Since: ArcGIS Maps SDK for JavaScript 4.17

Destroys the layer and any associated resources (including its portalItem, if it is a property on the layer). The layer can no longer be used once it has been destroyed.

The destroyed layer will be removed from its parent object like Map, WebMap, WebScene, Basemap, Ground, or GroupLayer.

See also

• Map.destroy()
• WebMap.destroy()
• WebScene.destroy()
• Basemap.destroy()
• Ground.destroy()
• PortalItem.destroy()

emit(type, event){Boolean}inherited

Since: ArcGIS Maps SDK for JavaScript 4.5

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

fetchAttributionData(){Promise<object>}inherited

Fetches custom attribution data for the layer when it becomes available.

Returns

Type	Description
Promise<object>	Resolves to an object containing custom attribution data for the layer.

getFeatureType(feature){FeatureType}

Since: ArcGIS Maps SDK for JavaScript 4.7

Returns a FeatureType describing the feature's type. This is applicable if the layer containing the feature has a typeIdField.

Parameter

feature Graphic A feature from this layer.

Returns

Type	Description
FeatureType	The FeatureType describing the feature's type.

getField(fieldName){Field}

Since: ArcGIS Maps SDK for JavaScript 4.11

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.

Example

// Get a range domain associated with the first feature
// returned from queryFeatures().
featureLayer.queryFeatures(query).then(function(results){
  const domain = featureLayer.getFieldDomain("Height", {feature: results.features[0]});
  console.log("domain", domain)
});

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.

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");
}

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.

The load() method only triggers the loading of the resource the first time it is called. The subsequent calls return the same promise.

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[] An event or an array of events to listen for.

listener Function The function to call when the event fires.

Returns

Type	Description
Object	Returns an event handler with a remove() method that should 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);
});

queryAttachments(attachmentQuery, options){Promise<object>}

Since: ArcGIS Maps SDK for JavaScript 4.9

Query information about attachments associated with features. It will return an error if the layer's capabilities.data.supportsAttachment property is false. Attachments for multiple features can be queried if the layer's capabilities.operations.supportsQueryAttachments is true.

Known Limitations

When the layer'scapabilities.operations.supportsQueryAttachments property is false, AttachmentQuery.objectIds property only accepts a single objectId.

Parameters

attachmentQuery AttachmentQuery autocast Autocasts from Object Specifies the attachment parameters for query.

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 an object containing AttachmentInfos grouped by the source feature objectIds.

See also

• capabilities.data.supportsAttachment

• capabilities.operations.supportsQueryAttachments

Example

layer.when(function () {
  // queryObjectIds for all features within the layer
  layer.queryObjectIds().then(function (objectIds) {
    // Define parameters for querying attachments,
    // query features where objectIds are less than 735,
    // and only query jpeg attachments for these features.
    let attachmentQuery = {
      objectIds: objectIds,
      definitionExpression: "OBJECTID < 735",
      attachmentTypes: ["image/jpeg"]
    };

    // Only pass in one objectId for attachmentQuery.objectIds
    // if the layer's capabilities.operations.supportsQueryAttachments is false
    layer.queryAttachments(attachmentQuery).then(function (attachments) {
      // Print out all returned attachment infos to the console.
      attachmentQuery.objectIds.forEach(function (objectId) {
        if (attachments[objectId]) {
          let attachment = attachments[objectId];
          console.group("attachment for", objectId);
          attachment.forEach(function (item) {
            console.log("attachment id", item.id);
            console.log("content type", item.contentType);
            console.log("name", item.name);
            console.log("size", item.size);
            console.log("url", item.url);
            console.groupEnd();
          });
        }
      });
    })
    .catch(function (error) {
      console.log("attachment query error", error);
    })
  });
});

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

Executes a Query against the feature service 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.

To query for the extent of features/graphics available to or visible in the View on the client rather than making a server-side query, you must use the FeatureLayerView.queryExtent() method.

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

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 feature service 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.

To query for the count of features/graphics available to or visible in the View on the client rather than making a server-side query, you must use the FeatureLayerView.queryFeatureCount() method.

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

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 feature service and returns a FeatureSet, which can be accessed using the .then() method once the promise resolves. A FeatureSet contains an array of Graphic features. See the querying section for more information on how to query features from a layer.

To query features/graphics available to or visible in the View on the client rather than making a server-side query, you must use the FeatureLayerView.queryFeatures() method.

When querying a service with z-values and no vertical coordinate system information, the z-values will automatically be converted to match the outSpatialReference units. Example: The service has a horizontal spatial reference using feet units and the query is made with outSpatialReference based on meter units, then queryFeatures() automatically converts the values from feet to meter units.

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

• Query and filter guide

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

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

// query all features from the layer and only return
// attributes specified in outFields.
const query = { // autocasts as Query
  where: "1=1", // select all features
  returnGeometry: false,
  outFields: ["State_Name", "City_Name", "pop2010"]
};

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

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

Executes a Query against the feature service 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.

To query for ObjectIDs of features/graphics available to or visible in the View on the client rather than making a server-side query, you must use the FeatureLayerView.queryObjectIds() method.

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

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

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

queryRelatedFeatures(relationshipQuery, options){Promise<object>}

Since: ArcGIS Maps SDK for JavaScript 4.9

Executes a RelationshipQuery against the feature service and returns FeatureSets grouped by source layer or table objectIds.

Parameters

relationshipQuery RelationshipQuery autocast Autocasts from Object Specifies relationship parameters for querying related features or records from a layer or a table.

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 FeatureSets grouped by source layer/table objectIds. Each FeatureSet contains an array of Graphic features including the values of the fields requested by the user.

See also

• relationships property

• Sample - Query Related Features

Example

const objectIds = [385, 416];

// relationship query parameter
const query = {
  outFields: ["*"],
  relationshipId: relationshipId,
  objectIds: objectIds
}

// query related features for given objectIds
layer.queryRelatedFeatures(query).then(function (result) {
  objectIds.forEach(function (objectId) {
    // print out the attributes of related features if the result
    // is returned for the specified objectId
    if (result[objectId]) {
      console.group("relationship for feature:", objectId)
      result[objectId].features.forEach(function (feature) {
        console.log("attributes", JSON.stringify(feature.attributes));
      });
      console.groupEnd();
    }
  });
}).catch(function (error) {
  console.log("error from queryRelatedFeatures", error);
});

queryRelatedFeaturesCount(relationshipQuery, options){Promise<object>}

Since: ArcGIS Maps SDK for JavaScript 4.17

Executes a RelationshipQuery against the feature service and when resolved, it returns an object containing key value pairs. Key in this case is the objectId of the feature and value is the number of related features associated with the feature.

Parameters

relationshipQuery RelationshipQuery autocast Autocasts from Object Specifies relationship parameters for querying related features or records from a layer or a table.

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 an object containing key value pairs. Key in this case is the objectId of the feature and value is the number of related features.

See also

• relationships property

• Sample - Query Related Features

Example

const objectIds = [385, 416];

// relationship query parameter
const query = {
  outFields: ["*"],
  relationshipId: relationshipId,
  objectIds: objectIds
}

// query related features for given objectIds
layer.queryRelatedFeaturesCount(query).then(function (count) {
  console.log("queryRelatedFeaturesCount", count);
  // this will print out
  // {385: 91, 416: 23}
}).catch(function (error) {
  console.log("error from queryRelatedFeatures", error);
});

queryTopFeatureCount(topFeaturesQuery, options){Promise<number>}

Since: ArcGIS Maps SDK for JavaScript 4.20

Executes a TopFeaturesQuery against a feature service and returns the count of features or records that satisfy the query.

Known Limitations

• Currently, the queryTopFeatureCount is only supported with server-side FeatureLayers.

Parameters

topFeaturesQuery TopFeaturesQuery autocast Autocasts from Object Specifies the attributes, spatial, temporal, and top filter of the query. The topFilter parameter must be set.

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.

See also

• Sample - Query features from a FeatureLayer

• Query and filter guide

• TopFeaturesQuery
• TopFilter

Example

// set the query to return a count
// of features that has most sales grouped by regions.
// top query will run against all features available in the service
const query = new TopFeaturesQuery({
  topFilter: new TopFilter({
    topCount: 1,
    groupByFields: ["Region"],
    orderByFields: ["Sales DESC"]
  })
});
featureLayer.queryTopFeatureCount(query)
  .then(function(response){
     // returns the number of the features that have the most sales by region.
   });

queryTopFeatures(topFeaturesQuery, options){Promise<FeatureSet>}

Since: ArcGIS Maps SDK for JavaScript 4.20

Executes a TopFeaturesQuery against a feature service and returns a FeatureSet once the promise resolves. The FeatureSet contains an array of top features grouped and ordered by specified fields. For example, you can call this method to query top three counties grouped by state names while ordering them based on their populations in a descending order.

Known Limitations

• Currently, the queryTopFeatures is only supported with server-side FeatureLayers.

Parameters

topFeaturesQuery TopFeaturesQuery autocast Autocasts from Object Specifies the attributes, spatial, temporal, and top filter of the query. The topFilter parameter must be set.

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 features that are grouped and ordered specified fields.

See also

• Sample - Query features from a FeatureLayer

• Query and filter guide

• TopFeaturesQuery
• TopFilter

Example

// Query the most visited national parks in each state
// and order them by the most visited
// query will run against all features available in the service
const query = new TopFeaturesQuery({
  outFields: ["State, TOTAL, Park"],
  topFilter: new TopFilter({
    topCount: 1,
    groupByFields: ["State"],
    orderByFields: ["TOTAL DESC"]
  })
});
featureLayer.queryTopFeatures(query)
  .then(function(response){
     // returns a feature set with features containing the most visited
     // national park in each state ordered by the number of visits.
     // The following attributes are returned as well: State, TOTAL, Park
   });

queryTopFeaturesExtent(topFeaturesQuery, options){Promise<object>}

Since: ArcGIS Maps SDK for JavaScript 4.20

Executes a TopFeaturesQuery against a feature service and returns the Extent of features that satisfy the query.

Known Limitations

• Currently, the queryTopFeaturesExtent is only supported with server-side FeatureLayers.

Parameters

topFeaturesQuery TopFeaturesQuery autocast Autocasts from Object Specifies the attributes, spatial, temporal, and top filter of the query. The topFilter parameter must be set.

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 query. extent Extent The extent of features that satisfy the query.

See also

• Sample - Query features from a FeatureLayer

• Query and filter guide

• TopFeaturesQuery
• TopFilter

Example

// Get the count and extent of the three highest magnitude earthquakes
// in each region.
const query = new TopFeaturesQuery({
  where: "mag >= 6",
  geometry: studyExtent,
  topFilter: new TopFilter({
    topCount: 3,
    groupByFields: ["region"],
    orderByFields: ["mag DESC"]
  })
});
featureLayer.queryTopFeaturesExtent(query)
  .then(function(response){
     // returns the count and extent of top three earthquakes within each region
   });

queryTopObjectIds(topFeaturesQuery, options){Promise<number[]>}

Since: ArcGIS Maps SDK for JavaScript 4.20

Executes a TopFeaturesQuery against a feature service and returns an array of Object IDs of features that satisfy the query.

Known Limitations

• Currently, the queryTopObjectIds is only supported with server-side FeatureLayers.

Parameters

topFeaturesQuery TopFeaturesQuery autocast Autocasts from Object Specifies the attributes, spatial, temporal, and top filter of the query. The topFilter parameter must be set.

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 features satisfying the query.

See also

• Sample - Query features from a FeatureLayer

• Query and filter guide

• TopFeaturesQuery
• TopFilter

Example

// Get the objectIds top three earthquakes
// grouped by regions and ordered by their magnitude levels
// top query will only run against earthquakes that have mag >=6.
const query = new TopFeaturesQuery({
  where: "mag >= 6",
  topFilter: new TopFilter({
    topCount: 3,
    groupByFields: ["region"],
    orderByFields: ["mag DESC"]
  })
});
featureLayer.queryTopObjectIds(query)
  .then(function(response){
     // returns an array of object ids of top three earthquakes within each region
   });