SnappingOptions | References | ArcGIS Maps SDK for JavaScript

import SnappingOptions from "@arcgis/core/views/interactive/options/SnappingOptions.js";

const SnappingOptions = await $arcgis.import("@arcgis/core/views/interactive/options/SnappingOptions.js");

Inheritance: SnappingOptions→Accessor

Subclasses: SnappingOptions

Since: ArcGIS Maps SDK for JavaScript 5.2

Configures snapping while drawing, editing, or placing analyses.

Use view.options.snapping to share snapping options across supported components, view models, and analyses. See ViewOptions for supported tools and opt-in requirements.

Snapping can also be configured on the Sketch and Editor components or their view models, SketchViewModel and EditorViewModel.

Enable self snapping, feature snapping, or both, as described below. In tools that support the shortcut, holding down the CTRL key temporarily toggles snapping on or off.

Self snapping (Geometry guides)

Self snapping is set via the selfEnabled property. This means that while a user is actively creating or updating a feature or graphic, they will see visualizations to help identify perpendicular and parallel lines, in addition to visualizations which aid in snapping to an extension of an existing feature. The following briefly demonstrates what self snapping looks like in a 2D application. Although this is shown for 2D, the same premise applies for 3D as well.

Feature snapping

Feature snapping is set via the featureEnabled property. It provides the ability to snap vertices of a graphic or feature that is currently being drawn or reshaped to that of an existing feature's vertex, edge, or end point. These existing features belong to layers within the Map. See featureSources for configuring sources or using the automatic sources provided by view options. The following two images demonstrate feature snapping in a 2D application. Similar to self snapping, the same premise applies for 3D as well.

The above shows feature snapping to an existing feature's vertex endpoint and edge while creating a new feature. The bottom demonstrates taking an existing feature and reshaping its geometry to snap to another feature's vertex points.

Things to consider: Layer types currently supported for snapping are: FeatureLayer, GraphicsLayer (except Mesh geometries), GeoJSONLayer, WFSLayer, CSVLayer, MapNotesLayer (2D only), 3D Object SceneLayer (3D only), and BuildingSceneLayer (3D only). Snapping is not yet implemented when using the Sketch widget's circle tool. It will be addressed in a future release. Enabling snapping via the CTRL key is not currently supported using the Sketch widget's rectangle and circle tools. However, snapping can still be activated by setting the enabled property to true in the Sketch widget or its view model. Note that this enables snapping for all tools. This behavior is subject to change in a future release.

Name	Details	3D Example	2D Example
Rectangle	Snap lines that are perpendicular to each other
Parallel	Snap to all parallel lines
Extension	Snap to an extension of the current shape
Vertex (as seen when updating geometries)	Snap vertices to an existing vertex

See also

Example

// Create a new instance of Sketch, and
// specify a layer in featureSources.
// This enables feature snapping on that layer.
const sketch = new Sketch({
  layer: graphicsLayer,
  view: view,
  snappingOptions: { // autocasts to SnappingOptions()
    enabled: true, // snapping is turned on
    // assigns a collection of FeatureSnappingLayerSource() and enables feature snapping on this layer
    featureSources: [{ layer: graphicsLayer, enabled: true }]
  }
});

Constructors

Constructor

Parameters

Parameter	Type	Description	Required
properties	SnappingOptionsProperties

See the properties table for a list of all the properties that may be passed into the constructor.

Properties

Any properties can be set, retrieved or listened to. See the Watch for changes topic.

Property	Type	Class
attributeRulesEnabled	boolean
declaredClass readonly inherited	string	Accessor
distance	number
enabled	boolean
featureEnabled	boolean
featureSources	Collection<FeatureSnappingLayerSource>
gridEnabled	boolean
selfEnabled	boolean

attributeRulesEnabled

Property

Type: boolean

When true, enables support for attribute rule-based snapping. When enabled, resources needed for rule-based snapping, including any Utility Networks present in the map, will be automatically loaded.

Default value: false

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.

distance

Property

Type: number

Snapping distance for snapping in pixels.

Default value: 5

enabled

Property

Type: boolean

Indicates whether snapping is enabled.

The default is false for a new SnappingOptions instance. Snapping configured through ViewOptions.snapping is disabled by default in a MapView and enabled by default in a SceneView.

Default value: false

featureEnabled

Property

Type: boolean

Indicates whether feature snapping is enabled.

Default value: true

featureSources

autocast Property

Type: Collection<FeatureSnappingLayerSource>

List of sources for feature snapping. See FeatureSnappingLayerSource for supported layer sources.

When used through ViewOptions.snapping, supported layers in the view's map are used automatically if this property has not been explicitly configured. Explicitly configuring this property replaces the automatic source list.

gridEnabled

Property

Type: boolean

Turns the grid on or off. The grid is a network of columns and rows used to divide the view into equal-area squares. The GridControls provides a user interface to interact and configure the grid's properties.

Note

It is recommended to wait for the view to be loaded first before setting the gridEnabled prop in the GridControls constructor. The grid is dependent on the view to be loaded first for it to be displayed.

This grid is only supported in a 2D MapView.

See also

GridControls

Default value: false

Example

// Turn on the grid programmatically for the GridControls.
// Wait for the view to load first.
view.when(() => {
  const gridControls = new GridControls({
    view,
    snappingOptions: {
      enabled: true,
      gridEnabled: true
    }
  });
  // Add GridControls to the view
  view.ui.add(gridControls, "top-left");
});

selfEnabled

Property

Type: boolean

Indicates whether self snapping is enabled within one feature while drawing or reshaping.

Default value: true