The parameters for the onElementGroupChange listener.

Properties

elementGroup

elementGroup: null | ElementGroup

The Felt SDK lets you get information about the elements in the map, and the groups that they belong to.

Index

Controller

• ElementsController

Element Groups

• ElementGroup

• GetElementGroupsConstraint

• ElementGroupChangeCallbackParams

Elements

• Element

• GetElementsConstraint

• ElementChangeCallbackParams

Properties

id

id: string

The string identifying the element

type

type: string

The type of element, such as a Place, Polygon, Line, Route, etc.

groupId

groupId: null | string

The ID of the element group that the element belongs to, or null if the element is not inside an element group.

name

name: null | string

The name of the element can be displayed in the Legend, depending on how the element's legend is configured in its style.

description

description: null | string

The element description forms part of the element's metadata. This is visible to users via the element info button in the legend.

attributes

attributes: Record<string, unknown>

The attributes of the element, which can be added via the Element Inspector under the Detail tab.

Properties

id

id: string

A string identifying the element group.

name

name: string

The name of the element group. This is shown in the legend.

caption

caption: null | string

The caption of the element group. This is shown in the legend.

elementIds

elementIds: string[]

The ids of the elements in the element group.

Remarks

You can use these ids to get the full element objects via the getElements method.

visible

visible: boolean

Whether the element group is visible or not.

shownInLegend

shownInLegend: boolean

Whether the element group is shown in the legend or not.

The parameters for the onElementChange listener.

Properties

element

element: null | Element

The new data for the element or null if the element was removed.

The constraints to apply when getting element groups.

Properties

ids?

optional ids: string[]

The ids of the element groups to get.

The constraints to apply when getting elements.

Properties

ids?

optional ids: string[]

The ids of the elements to get.

The Elements controller allows you to get information about the elements on the map, and make changes to their visibility.

Extended by

• FeltController

Methods

getElement()

getElement(id: string): Promise<null | Element>

Get a single element from the map by its id.

Parameters

Returns

Promise<null | Element>

The requested element.

Example

const element = await felt.getElement("element-1");

getElementGeometry()

getElementGeometry(id: string): Promise<null | Geometry>

Get the geometry of an element.

Parameters

Returns

Promise<null | Geometry>

Example

const geometry = await felt.getElementGeometry("element-1");
console.log(geometry?.type, geometry?.coordinates);

getElements()

getElements(constraint?: GetElementsConstraint): Promise<(null | Element)[]>

Gets elements from the map, according to the constraints supplied. If no constraints are supplied, all elements will be returned.

Parameters

Returns

Promise<(null | Element)[]>

All elements on the map.

Remarks

The elements in the map, ordered by the order specified in Felt. This is not necessarily the order that they are drawn in, as Felt draws points above lines and lines above polygons, for instance.

Example

const elements = await felt.getElements();

getElementGroup()

getElementGroup(id: string): Promise<null | ElementGroup>

Get an element group from the map by its id.

Parameters

Returns

Promise<null | ElementGroup>

The requested element group.

Example

felt.getElementGroup("element-group-1");

getElementGroups()

getElementGroups(constraint?: GetElementGroupsConstraint): Promise<(null | ElementGroup)[]>

Gets element groups from the map, according to the filters supplied. If no constraints are supplied, all element groups will be returned in rendering order.

Parameters

Returns

Promise<(null | ElementGroup)[]>

The requested element groups.

Example

const elementGroups = await felt.getElementGroups({ ids: ["element-group-1", "element-group-2"] });

setElementGroupVisibility()

setElementGroupVisibility(visibility: SetVisibilityRequest): Promise<void>

Hide or show element groups with the given ids.

Parameters

Returns

Promise<void>

Example

felt.setElementGroupVisibility({ show: ["element-group-1", "element-group-2"], hide: ["element-group-3"] });

Events

onElementChange()

onElementChange(args: {options: {id: string; };handler: (change: ElementChangeCallbackParams) => void; }): VoidFunction

Adds a listener for when an element changes.

Parameters

Returns

VoidFunction

A function to unsubscribe from the listener

Example

const unsubscribe = felt.onElementChange({
  options: { id: "element-1" },
  handler: ({element}) => console.log(element.id),
});

// later on...
unsubscribe();

onElementGroupChange()

onElementGroupChange(args: {options: {id: string; };handler: (change: ElementGroupChangeCallbackParams) => void; }): VoidFunction

Adds a listener for when an element group changes.

Parameters

Returns

VoidFunction

A function to unsubscribe from the listener

Example

const unsubscribe = felt.onElementGroupChange({
  options: { id: "element-group-1" },
  handler: elementGroup => console.log(elementGroup.id),
});

// later on...
unsubscribe();