@deltares/fews-web-oc-composables

---

@deltares/fews-web-oc-composables / useWmsLegend

Function: useWmsLegend()

useWmsLegend(options): UseWmsLegendReturn

Defined in: useWms/useWmsLegend.ts:76

Alpha

This API is not yet stable and may change in future versions.

Loads a WMS legend graphic for a layer, reactively reloading when legend options change and supporting automatic refresh through refresh. Clears the previous graphic when those options change and preserves the last successful graphic when a refresh for the same options fails. By default, no scheduled refresh policies are enabled.

Parameters

options

UseWmsLegendOptions

Member	Type	Description
colorScaleRange?	MaybeRefOrGetter<string>	Optional "min,max" color scale range override.
enabled?	Ref<boolean, boolean>	Controls whether requests and automatic refreshes are enabled.
layerName	MaybeRefOrGetter<string | undefined>	Name of the layer to load the legend for.
refresh?	UseWmsRefreshOptions	Configuration for automatic request refreshing.
style?	MaybeRefOrGetter<Style>	Optional WMS style to render the legend with.
useDisplayUnits	MaybeRefOrGetter<boolean>	Whether to render the legend using display units.
webservice?	PiWebserviceOptions	Optional webservice configuration for standalone usage. When omitted, the host-provided webservice context is used.

Request configuration. See UseWmsLegendOptions.

Returns

UseWmsLegendReturn

Member	Type	Description
cancel	() => void	Cancels the currently running request, if any.
error	Readonly<Ref<Error | null>>	Error from the most recent request, or null when there is no error.
fetch	() => Promise<void>	Fetches the requested WMS data immediately.
hasAttempted	Readonly<Ref<boolean>>	Whether a request has completed for the current inputs, successfully or not.
hasLoaded	Readonly<Ref<boolean>>	Whether a successful response is available for the current inputs.
lastRefreshAt	Readonly<Ref<Date | undefined>>	Time at which the most recent refresh completed successfully.
lastTriggerPolicy	Readonly<Ref<RefreshPolicy | undefined>>	Policy that caused the most recent refresh.
legendGraphic	Readonly<Ref<GetLegendGraphicResponse | undefined>>	The loaded WMS legend graphic.
loading	Readonly<Ref<boolean>>	Whether the initial request is in progress.
pauseRefresh	() => void	Pauses automatic refreshes.
refreshing	Readonly<Ref<boolean>>	Whether a subsequent request is in progress.
requestRefresh	() => void	Requests a refresh through the refresh coordinator.
resumeRefresh	() => void	Resumes automatic refreshes.

The legend graphic and request state. See UseWmsLegendReturn.

Example

import { ref } from 'vue'
import { useWmsLegend } from '@deltares/fews-web-oc-composables'

const options = {
  layerName: ref('waterlevel'),
  useDisplayUnits: true,
  webservice: { baseUrl: 'https://example.localhost/fewswebservices' },
  refresh: { policies: ['onInterval'], intervalMs: 30_000 },
}

const { legendGraphic, loading, error } = useWmsLegend(options)