var webmap = new WebMap({
  portalItem: { // autocasts as new PortalItem()
    id: "e691172598f04ea8881cd2a4adaa45ba"
  }
});

var view = new MapView({
  map: webmap,  // The WebMap instance created above
  container: "viewDiv"
});

Property Overview

Property Details

allLayersCollection<Layer>readonly inherited

A flat collection of all the layers in the map. This collection contains basemap layers, operational layers and ground layers. Group Layers and their children layers are also part of this collection. Reference layers in the basemap will always be included at the end of the collection.

Layers should not be added directly to this collection. They must only be added via the layers, basemap or ground properties.

Example:

// Find a layer with title "US Counties"
var foundLayer = map.allLayers.find(function(layer) {
 return layer.title === "US Counties";
});

// Create a filtered collection of the non-group layers
var nonGroupLayers = map.allLayers.filter(function(layer) {
 return !foundLayer.layers;
});

// Listen for any layer being added or removed in the Map
map.allLayers.on("change", function(event) {
 console.log("Layer added: ", event.added);
 console.log("Layer removed: ", event.removed);
 console.log("Layer moved: ", event.moved);
});

applicationPropertiesObject

Object responsible for containing the viewing and editing properties of the WebMap.

basemapBasemapautocast inherited

Autocasts from String|Object

Specifies a basemap for the map. The basemap is a set of tile layers that give geographic context to the MapView or SceneView and the other operational layers in the map.

This value can be an instance of Basemap or one of the strings listed in the table below.

Value	Description
streets
satellite
hybrid
topo
gray
dark-gray
oceans
national-geographic
terrain
osm
dark-gray-vector
gray-vector
streets-vector
topo-vector
streets-night-vector
streets-relief-vector
streets-navigation-vector

Example:

// Set the basemap in the constructor
var map = new Map({
  basemap: "streets"
});

// Set the basemap after the map instance is created
map.basemap = "topo";

bookmarksCollection<Bookmark>autocast

An array of saved geographic extents that allow end users to quickly navigate to a particular area of interest.

declaredClassStringreadonly inherited

Since: ArcGIS API for JavaScript 4.7

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

groundGroundautocast inherited

Autocasts from String|Object

Specifies the surface properties for the map. This property is only relevant when adding the map to a 3D SceneView. It renders the terrain or topographical variations in the real world on the map's surface with a collection of ElevationLayer.

This value can be an instance of Ground, or one of the following strings:

• world-elevation for a default instance of ground using the Terrain3D Service.
• world-topobathymetry for an instance of ground that combines surface elevation and bathymetry using the TopoBathy3D Service.

The ground may not be set to null or undefined, it is guaranteed to always contain an instance of type Ground. The elevation can be removed from the ground by setting the ground property to a new empty Ground instance or by removing all the ground layers.

See also:

• ElevationLayer
• Ground

Examples:

// Use the world elevation service
var map = new Map({
  basemap: "topo",
  ground: "world-elevation"
});

// Create a map with the world elevation layer overlaid by a custom elevation layer
var worldElevation = ElevationLayer({
  url: "//elevation3d.arcgis.com/arcgis/rest/services/WorldElevation3D/Terrain3D/ImageServer"
});
var customElevation = ElevationLayer({
  url: "https://my.server.com/arcgis/rest/service/MyElevationService/ImageServer"
});
var map = new Map({
  basemap: "topo",
  ground: new Ground({
   layers: [ worldElevation, customElevation ]
  })
});

initialViewPropertiesInitialViewPropertiesautocast

The initial view of the WebMap. This object contains properties such as viewpoint, spatialReference, that should be applied to the view when the WebMap loads.

layersCollection<Layer>autocast inherited

Autocasts from Layer[]

A collection of operational layers. This property only contains interactive operational layers, such as FeatureLayers, WebTileLayers and GraphicsLayers that may be queried, assigned different renderers, analyzed, etc. It does not include basemaps.

A layer is a collection of one or more features, or graphics, that represent real-world phenomena. Each feature contains a symbol and geographic data that allows it to be rendered on the map as a graphic with spatial context. Features within the layer may also contain data attributes that provide additional information that may be viewed in popup windows and used for rendering the layer.

Layers may be added in the constructor, with the add() or addMany() methods, or directly to the layers collection using add() or addMany().

A layer may only be added to one parent. Adding the same layer to multiple Maps or GroupLayers is not possible. If you attempt to do so, the layer will automatically be removed from its current parent and placed in the new parent.

var layer = new GraphicsLayer();
// The layer belongs to map1
map1.layers.add(layer);
// The layer now belongs to map2
// and implicitly does: map1.layers.remove(layer)
map2.layers.add(layer);

Example:

// Add layers in the constructor of Map using an array
var fl = new FeatureLayer(url);
var gl = new GraphicsLayer();
var map = new Map({
  layers: [fl, gl]
});

// Add layers using add()
map.addMany([fl, gl]);

// Add layers using layers collection
map.layers.addMany([fl, gl]);

loadedBooleanreadonly

Indicates whether the instance has loaded. When true, the properties of the object can be accessed. A WebMap is considered loaded when its layers and basemap are created, but not yet loaded.

Default Value:false

loadErrorErrorreadonly

The Error object returned if an error occurred while loading.

Default Value:null

loadStatusStringreadonly

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.

Default Value:not-loaded

portalItemPortalItemautocast

The portal item from which the WebMap is loaded.

presentationObject

Provides multiple slides. Each slide has a different "title", "extent", "basemap", "layers" etc.

sourceVersionObjectreadonly

Since: ArcGIS API for JavaScript 4.1

The version of the source document from which the WebMap was read. The WebMap must be version 2.x to load into an app.

Properties:

major Number The major version of the WebMap.

minor Number The minor version of the WebMap.

tablesObject[]

An array of table objects in the WebMap.

widgetsObject

The widgets object contains widgets that should be exposed to the user.

Method Overview

Method Details

add(layer, index)inherited

Adds a layer to the layers collection.

Parameters:

layer Layer|Promise<Layer> Layer or a Promise<Layer> to be added to the layers collection.

index Number optional A layer can be added at a specified index in the layers collection. If no index is specified or the index specified is greater than the current number of layers, the layer is automatically appended to the list of layers in the layers collection and the index is normalized.

addMany(layers, index)inherited

Adds a layer or an array of layers to the layers collection.

Parameters:

layers Layer[] Layer(s) to be added to the layers collection.

index Number optional A layer can be added at a specified index in the layers collection. If no index is specified or the index specified is greater than the current number of layers, the layer is automatically appended to the list of layers in the layers collection and the index is normalized.

findLayerById(layerId){Layer}inherited

Returns a layer based on the given layer id.

Parameter:

layerId String The ID assigned to the layer.

Returns:

Type	Description
Layer	Returns the requested layer object.

isFulfilled(){Boolean}

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}

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}

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(){Promise}

Triggers the loading of the WebMap instance.

A WebMap is considered loaded when its operational layers and basemap are fully created. When created with a portalItem, load() will first fetch its data to create the content, otherwise it resolves immediately.

The MapView automatically calls the load() method when a WebMap instance is added to its map property so it can display in the view and load each individual layer. If the WebMap is used outside of a view, for example to preload it, you must call load() explicitly to interact with its resources.

Returns:

Type	Description
Promise	Resolves when the WebMap is loaded.

See also:

• portalItem

Example:

require([
  "esri/WebMap",

  "dojo/promise/all"
], function(
  WebMap,
  all
) {

  var map = new WebMap({
    portalItem: {
      id: "e691172598f04ea8881cd2a4adaa45ba"
    }
  });

  map.load()
    .then(function() {
      // load the basemap to get its layers created
      return map.basemap.load();
    })
    .then(function() {
      // grab all the layers and load them
      var allLayers = map.allLayers;
      var promises = allLayers.map(function(layer) {
        return layer.load();
      });
      return all(promises.toArray());
    })
    .then(function(layers) {
      // each layer load promise resolves with the layer
      console.log("all " + layers.length + " layers loaded");
    })
    .catch(function(error) {
      console.error(error);
    });
});

loadAll(){Promise<WebMap>}

Since: ArcGIS API for JavaScript 4.9

Loads all the externally loadable resources associated with the webmap. For the webmap this will load the ground, basemap and layers.

Returns:

Type	Description
Promise<WebMap>	Resolves when all the loadable resources have been loaded.

See also:

• load

remove(layer){Layer}inherited

Removes the specified layer from the layers collection.

Parameter:

layer Layer Layer to remove from the layers collection.

Returns:

Type	Description
Layer	Returns the layer removed from the layers collection.

removeAll(){Layer[]}inherited

Removes all layers.

Returns:

Type	Description
Layer[]	Returns the layers removed from the layers collection.

removeMany(layers){Layer[]}inherited

Removes the specified layers.

Parameter:

layers Layer[] Array of layers to remove from the layers collection.

Returns:

Type	Description
Layer[]	Returns the layers removed from the layers collection.

reorder(layer, index){Layer}inherited

Changes the layer order. The first layer added is always the base layer, even if its order is changed.

Parameters:

layer Layer The layer to be moved.

index Number The index location for placing the layer. The bottom-most layer has an index of 0.

Returns:

Type	Description
Layer	Returns the layer that was moved.

when(callback, errback){Promise}

Since: ArcGIS API for JavaScript 4.6

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

Parameters:

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

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

Returns:

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

Example:

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