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import LineOfSightLayerView from "@arcgis/core/views/layers/LineOfSightLayerView.js";
Inheritance:
LineOfSightLayerViewLayerViewAccessor

Represents the LayerView of a LineOfSightLayer after it has been added to a Map in a SceneView.

The line of sight layer view controls whether the LineOfSightLayer.analysis in its associated LineOfSightLayer can be created or edited interactively.

It allows to create an observer and/or targets interactively using the place() method, query the results, or make an existing analysis editable by enabling the interactive property.

The view for the layer can be retrieved using SceneView.whenLayerView().

// create new layer and add it to the map
const lineOfSightLayer = new LineOfSightLayer();
view.map.add(lineOfSightLayer);
// retrieve layer view for the layer
const lineOfSightLayerView = await view.whenLayerView(lineOfSightLayer);
See also

Properties

Any properties can be set, retrieved or listened to. See the Watch for changes topic.
PropertyTypeClass
declaredClass
readonly inherited
layer
readonly
results
readonly
spatialReferenceSupported
readonly inherited
suspended
readonly inherited
uid
readonly inherited
updating
readonly inherited
view
readonly inherited
visible
inherited
visibleAtCurrentScale
readonly inherited
visibleAtCurrentTimeExtent
readonly inherited

declaredClass

readonlyinherited Property
Type
string
Inherited from: Accessor
Since
ArcGIS Maps SDK for JavaScript 4.7

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

interactive

Property
Type
boolean

Enables interactivity for the layer. When set to true, manipulators will be displayed, allowing users to click and drag to edit the layer's LineOfSightLayer.analysis if it has a valid LineOfSightAnalysis.observer and LineOfSightAnalysis.targets. Right-clicking a target will remove it.

This property is automatically set to true when the analysis is assigned to a Line Of Sight component.

Default value
false

layer

readonly Property
Type
LineOfSightLayer

The layer this layer view represents.

results

readonly Property
Type
LineOfSightAnalysisView3D["results"]

Analysis results for each target.

The order of results matches the order of targets, so if the index of the target is known the collection can be indexed directly:

const layerView = await view.whenLayerView(lineOfSightLayer);
const result = layerView.results.at(targetIdx);

Given a target object, the results collection can also be searched:

const result = layerView.results.find((result) => result.target === targetObject);

spatialReferenceSupported

readonlyinherited Property
Type
boolean
Inherited from: LayerView
Since
ArcGIS Maps SDK for JavaScript 4.23

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

suspended

readonlyinherited Property
Type
boolean
Inherited from: LayerView

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

See also

uid

readonlyinherited Property
Type
string
Inherited from: IdentifiableMixin
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

readonlyinherited Property
Type
boolean
Inherited from: LayerView

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

readonlyinherited Property
Type
MapViewOrSceneView
Inherited from: LayerView
Since
ArcGIS Maps SDK for JavaScript 4.28

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

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

visible

autocast inherited Property
Type
boolean
Inherited from: LayerView

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

Default value
true

visibleAtCurrentScale

readonlyinherited Property
Type
boolean
Inherited from: LayerView
Since
ArcGIS Maps SDK for JavaScript 4.30

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

See also
Default value
true

visibleAtCurrentTimeExtent

readonlyinherited Property
Type
boolean
Inherited from: LayerView
Since
ArcGIS Maps SDK for JavaScript 4.30

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

MethodSignatureClass
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<LineOfSightPlacementResult>
when
inherited
when<TResult1 = this, TResult2 = never>(onFulfilled?: OnFulfilledCallback<this, TResult1> | null | undefined, onRejected?: OnRejectedCallback<TResult2> | null | undefined): Promise<TResult1 | TResult2>

emit

inherited Method
Signature
emit <Type extends EventNames<this>>(type: Type, event?: this["@eventTypes"][Type]): boolean
Type parameters
<Type extends EventNames<this>>
Inherited from: EventedMixin
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
ParameterTypeDescriptionRequired
type
Type

The name of the event.

event
this["@eventTypes"][Type]

The event payload.

Returns
boolean

true if a listener was notified

hasEventListener

inherited Method
Signature
hasEventListener <Type extends EventNames<this>>(type: Type): boolean
Type parameters
<Type extends EventNames<this>>
Inherited from: EventedMixin

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

Parameters
ParameterTypeDescriptionRequired
type
Type

The name of the event.

Returns
boolean

Returns true if the class supports the input event.

isFulfilled

inherited Method
Signature
isFulfilled (): boolean
Inherited from: EsriPromiseMixin

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

inherited Method
Signature
isRejected (): boolean
Inherited from: EsriPromiseMixin

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

inherited Method
Signature
isResolved (): boolean
Inherited from: EsriPromiseMixin

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

inherited Method
Signature
on <Type extends EventNames<this>>(type: Type, listener: EventedCallback<this["@eventTypes"][Type]>): ResourceHandle
Type parameters
<Type extends EventNames<this>>
Inherited from: EventedMixin

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

Parameters
ParameterTypeDescriptionRequired
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).

PropertyTypeDescription
removeFunctionWhen 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

Method
Signature
place (options?: AbortOptions | null | undefined): Promise<LineOfSightPlacementResult>
Since
ArcGIS Maps SDK for JavaScript 4.33

Starts the interactive placement of an observer and/or targets on the layer's LineOfSightLayer.analysis.

If the analysis does not have a valid observer yet, this method will allow placing an observer, which can be followed by zero or more targets. Otherwise, if it already has a valid observer, it will allow placing targets.

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. The promise resolves when the operation is productive, i.e. an oberver or any targets were added. Otherwise, if nothing was added or signal was aborted, the promise is rejected.

Calling this method sets interactive to true.

Parameters
ParameterTypeDescriptionRequired
options

An object specifying additional options.

Returns
Promise<LineOfSightPlacementResult>

A promise which resolves when the operation is completed successfully - i.e. the user places an observer and/or target(s), leaving the analysis in a valid state. Otherwise, the promise is rejected.

Example
const abortController = new AbortController();
try {
await layerView.place({ signal: abortController.signal });
} catch (error) {
if (error.name === "AbortError") {
console.log("Placement operation was cancelled.");
}
}
// cancel the placement operation at some later point
abortController.abort();

when

inherited Method
Signature
when <TResult1 = this, TResult2 = never>(onFulfilled?: OnFulfilledCallback<this, TResult1> | null | undefined, onRejected?: OnRejectedCallback<TResult2> | null | undefined): Promise<TResult1 | TResult2>
Type parameters
<TResult1 = this, TResult2 = never>
Inherited from: EsriPromiseMixin
Since
ArcGIS Maps SDK for JavaScript 4.6

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
ParameterTypeDescriptionRequired
onFulfilled

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 onFulfilled that may be used to chain additional functions.

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