import ViewshedLayerView from "@arcgis/core/views/layers/ViewshedLayerView.js";const ViewshedLayerView = await $arcgis.import("@arcgis/core/views/layers/ViewshedLayerView.js");- Since
- ArcGIS Maps SDK for JavaScript 4.31
Represents the LayerView of a ViewshedLayer after it has been added to a Map in a SceneView.
The viewshed layer view controls whether the viewsheds in its associated ViewshedLayer.source can be created or edited interactively.
It allows to create new viewsheds interactively using the place() method, or to make existing viewsheds selectable and editable by enabling the interactive property. To select a viewshed, hover and click on any of its manipulators.
The view for the layer can be retrieved using SceneView.whenLayerView().
// create new layer and add it to the mapconst viewshedLayer = new ViewshedLayer();view.map.add(viewshedLayer);
// retrieve layer view for the layerconst viewshedLayerView = await view.whenLayerView(viewshedLayer);Properties
| Property | Type | Class |
|---|---|---|
declaredClass readonly inherited | ||
| | ||
layer readonly | | |
| | ||
spatialReferenceSupported readonly inherited | ||
suspended readonly inherited | ||
uid readonly inherited | ||
updating readonly inherited | ||
view readonly inherited | ||
visible inherited | ||
visibleAtCurrentScale readonly inherited | ||
visibleAtCurrentTimeExtent readonly inherited |
interactive
- Type
- boolean
Enables interactivity for the layer. When set to true and the layer's
ViewshedLayer.source includes any
valid ViewshedAnalysis.viewsheds, they become selectable and editable.
- Default value
- false
selectedViewshed
The selected viewshed. If interactive is true, any viewshed in the
layer can be selected by clicking on it in the view. As long as interactive
remains true, the properties of the selected viewshed can be edited by interacting with
manipulators in the view.
spatialReferenceSupported
- Type
- boolean
Indicates if the spatialReference of the MapView or
Map component is supported by the layer view.
When false layer view will be suspended.
Known Limitations
This property is not supported for layer views of a 3D SceneView or Scene component.
- See also
uid
- Type
- string
- Since
- ArcGIS Maps SDK for JavaScript 4.33
An automatically generated unique identifier assigned to the instance. The unique id is generated each time the application is loaded.
updating
- Type
- boolean
Indicates if the layer view is making any updates that will impact what is displayed on the map.
For example, this value is true when renderer, definitionExpression, filter or effect is changed or
if the layer view is in the process of the fetching data.
Watch FeatureLayerView.dataUpdating property instead to only know when the data has been updated (e.g. to run statistics query on all feature available in the layer view).
- Default value
- false
Example
// Check for the first time layerView.updating becomes false. Then query for// features that are visible within the view associated with the layer view.await reactiveUtils.whenOnce(() => !layerView.updating);const query = layerView.createQuery();query.geometry = layerView.view.extent;const result = layerView.queryFeatures(query); view
- Type
- MapViewOrSceneView
Example
// Check for the first time layerView.updating becomes false. Then query for// features that are visible within the view associated with the layer view.await reactiveUtils.whenOnce(() => !layerView.updating);const query = layerView.createQuery();query.geometry = layerView.view.extent;const result = layerView.queryFeatures(query); visibleAtCurrentScale
- Type
- boolean
When true, the layer is visible in the view at the current scale. This applies to layers that have minScale and maxScale properties set.
Known Limitations
This property isn’t supported for tiled layers in 3D SceneView or in the Scene component
- Default value
- true
visibleAtCurrentTimeExtent
- Type
- boolean
When true, the layer is visible in the view's View.timeExtent. This applies to layers that have a Layer.visibilityTimeExtent.
- See also
- Default value
- true
Methods
| Method | Signature | Class |
|---|---|---|
createViewsheds(options?: AbortOptions | null | undefined): Promise<void> | | |
emit inherited | emit<Type extends EventNames<this>>(type: Type, event?: this["@eventTypes"][Type]): boolean | |
hasEventListener inherited | hasEventListener<Type extends EventNames<this>>(type: Type): boolean | |
isFulfilled inherited | isFulfilled(): boolean | |
isRejected inherited | isRejected(): boolean | |
isResolved inherited | isResolved(): boolean | |
on inherited | on<Type extends EventNames<this>>(type: Type, listener: EventedCallback<this["@eventTypes"][Type]>): ResourceHandle | |
place(options?: AbortOptions | null | undefined): Promise<ViewshedPlacementResult> | | |
when inherited | when<TResult1 = this, TResult2 = never>(onFulfilled?: OnFulfilledCallback<this, TResult1> | null | undefined, onRejected?: OnRejectedCallback<TResult2> | null | undefined): Promise<TResult1 | TResult2> |
createViewsheds
- Signature
-
createViewsheds (options?: AbortOptions | null | undefined): Promise<void>
Starts the interactive creation of new viewsheds and adds them to the layer ViewshedLayer.source.
The first click in the scene places the observer point and the second sets the viewshed's orientation.
The creation process will finish when the user double-clicks the mouse or presses the escape key. To stop the creation programmatically, pass an abort signal as an argument when calling the method.
This method is similar to the place() method, but it allows to create multiple viewsheds in a row.
Calling this method sets interactive to true.
Note that when placing viewsheds interactively, the viewshed is created with a 1.5 meter vertical offset from the scene. This behavior is subject to change in a future release.
Parameters
| Parameter | Type | Description | Required |
|---|---|---|---|
| options | An object specifying additional options. | |
Example
const abortController = new AbortController();
try { await viewshedLayerView.createViewsheds({ signal: abortController.signal });} catch (error) { if (error.name === "AbortError") { console.log("Creation operation was cancelled."); }}
// cancel the placement operation at some later pointabortController.abort(); emit
- Signature
-
emit <Type extends EventNames<this>>(type: Type, event?: this["@eventTypes"][Type]): boolean
- Type parameters
- <Type extends EventNames<this>>
Emits an event on the instance. This method should only be used when creating subclasses of this class.
hasEventListener
- Signature
-
hasEventListener <Type extends EventNames<this>>(type: Type): boolean
- Type parameters
- <Type extends EventNames<this>>
Indicates whether there is an event listener on the instance that matches the provided event name.
Parameters
| Parameter | Type | Description | Required |
|---|---|---|---|
| type | Type | The name of the event. | |
- Returns
- boolean
Returns true if the class supports the input event.
isFulfilled
- Signature
-
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
- boolean
Indicates whether creating an instance of the class has been fulfilled (either resolved or rejected).
isRejected
- Signature
-
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
- boolean
Indicates whether creating an instance of the class has been rejected.
isResolved
- Signature
-
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
- boolean
Indicates whether creating an instance of the class has been resolved.
on
- Signature
-
on <Type extends EventNames<this>>(type: Type, listener: EventedCallback<this["@eventTypes"][Type]>): ResourceHandle
- Type parameters
- <Type extends EventNames<this>>
Registers an event handler on the instance. Call this method to hook an event with a listener.
Parameters
| Parameter | Type | Description | Required |
|---|---|---|---|
| type | Type | An event or an array of events to listen for. | |
| listener | EventedCallback<this["@eventTypes"][Type]> | The function to call when the event fires. | |
- Returns
- ResourceHandle
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);}); place
- Signature
-
place (options?: AbortOptions | null | undefined): Promise<ViewshedPlacementResult>
- Since
- ArcGIS Maps SDK for JavaScript 4.33
Starts the interactive placement of a single viewshed, adding it to the layer's ViewshedLayer.source.
The first click in the scene places the observer point and the second sets the viewshed's orientation.
The placement operation will finish when the user presses the escape key. To stop the placing programmatically, pass an abort signal as an argument when calling the method.
Calling this method sets interactive to true.
Note that when placing viewsheds interactively, the viewshed is created with a 1.5 meter vertical offset from the scene. This behavior is subject to change in a future release.
Parameters
| Parameter | Type | Description | Required |
|---|---|---|---|
| options | An object specifying additional options. | |
- Returns
- Promise<ViewshedPlacementResult>
A promise which resolves when the operation is completed successfully or rejected if it is canceled.
Example
const abortController = new AbortController();
try { await viewshedLayerView.place({ signal: abortController.signal });} catch (error) { if (error.name === "AbortError") { console.log("Placement operation was cancelled."); }}
// cancel the placement operation at some later pointabortController.abort(); when
- Signature
-
when <TResult1 = this, TResult2 = never>(onFulfilled?: OnFulfilledCallback<this, TResult1> | null | undefined, onRejected?: OnRejectedCallback<TResult2> | null | undefined): Promise<TResult1 | TResult2>
when() may be leveraged once an instance of the class is created. This method takes two input parameters: an onFulfilled function and an onRejected function.
The onFulfilled executes when the instance of the class loads. The
onRejected executes if the instance of the class fails to load.
Parameters
| Parameter | Type | Description | Required |
|---|---|---|---|
| onFulfilled | OnFulfilledCallback<this, TResult1> | null | undefined | The function to call when the promise resolves. | |
| onRejected | The function to execute when the promise fails. | |
- Returns
- Promise<TResult1 | TResult2>
Returns a new promise for the result of
onFulfilledthat may be used to chain additional functions.
Example
// Although this example uses MapView, any class instance that is a promise may use when() in the same waylet 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});