MouseWheelZoom~MouseWheelZoom

import MouseWheelZoom from 'ol/interaction/MouseWheelZoom.js';

Allows the user to zoom the map by scrolling the mouse wheel.

new MouseWheelZoom(options) interaction/MouseWheelZoom.js, line 55

Name	Type	Description
`condition`	Condition \| undefined	A function that takes a `MapBrowserEvent` and returns a boolean to indicate whether that event should be handled. Default is `always`.
`onFocusOnly`	boolean (defaults to false)	When the map's target has a `tabindex` attribute set, the interaction will only handle events when the map has the focus.
`maxDelta`	number (defaults to 1)	Maximum mouse wheel delta.
`duration`	number (defaults to 250)	Animation duration in milliseconds.
`timeout`	number (defaults to 80)	Mouse wheel timeout duration in milliseconds.
`useAnchor`	boolean (defaults to true)	Enable zooming using the mouse's location as the anchor. When set to `false`, zooming in and out will zoom to the center of the screen instead of zooming on the mouse's location.
`constrainResolution`	boolean (defaults to false)	If true, the mouse wheel zoom event will always animate to the closest zoom level after an interaction; false means intermediary zoom levels are allowed.

Fires:

change (BaseEvent) - Generic change event. Triggered when the revision counter is increased.
change:active (ObjectEvent)
error (BaseEvent) - Generic error event. Triggered when an error occurs.
propertychange (ObjectEvent) - Triggered when a property is changed.

Extends

Interaction

Observable Properties

Name	Type	Settable	ObjectEvent type	Description
`active`	boolean	yes	`change:active`	`true` if the interaction is active, `false` otherwise.

Methods

changed() inherited Observable.js, line 68

Increases the revision counter and dispatches a 'change' event.

dispatchEvent(event){boolean | undefined} inherited events/Target.js, line 85

Dispatches an event and calls all listeners listening for events of this type. The event parameter can either be a string or an Object with a type property.

Name	Type	Description
`event`	BaseEvent \| string	Event object.

Returns:

false if anyone called preventDefault on the event object or if any of the listeners returned false.

get(key){*} inherited Object.js, line 136

Gets a value.

Name	Type	Description
`key`	string	Key name.

Returns:

Value.

getActive(){boolean} inherited interaction/Interaction.js, line 82

Return whether the interaction is currently active.

Returns:

true if the interaction is active, false otherwise.

getKeys(){Array.<string>} inherited Object.js, line 149

Get a list of object property names.

Returns:

List of property names.

getMap(){Map | null} inherited interaction/Interaction.js, line 91

Get the map associated with this interaction.

Returns:

Map.

getProperties(){NoInfer.<Properties>} inherited Object.js, line 158

Get an object of all property names and values.

Returns:

Object.

getRevision(){number} inherited Observable.js, line 79

Get the version number for this object. Each time the object is modified, its version number will be incremented.

Returns:

Revision.

on(type, listener){EventsKey | Array<EventsKey>} inherited Observable.js, line 152

Listen for a certain type of event.

Name	Type	Description
`type`	string \| Array.<string>	The event type or array of event types.
`listener`	function	The listener function.

Returns:

Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.

once(type, listener){EventsKey | Array<EventsKey>} inherited Observable.js, line 164

Listen once for a certain type of event.

Name	Type	Description
`type`	string \| Array.<string>	The event type or array of event types.
`listener`	function	The listener function.

Returns:

Unique key for the listener. If called with an array of event types as the first argument, the return will be an array of keys.

set(key, value, silent) inherited Object.js, line 218

Sets a value.

Name	Type	Description
`key`	string	Key name.
`value`	*	Value.
`silent`	boolean \| undefined	Update without triggering an event.

setActive(active) inherited interaction/Interaction.js, line 111

Activate or deactivate the interaction.

Name	Type	Description
`active`	boolean	Active.

setMouseAnchor(useAnchor) interaction/MouseWheelZoom.js, line 366

Enable or disable using the mouse's location as an anchor when zooming

Name	Type	Description
`useAnchor`	boolean	true to zoom to the mouse's location, false to zoom to the center of the map

setProperties(values, silent) inherited Object.js, line 238

Sets a collection of key-value pairs. Note that this changes any existing properties and adds new ones (it does not remove any existing properties).

Name	Type	Description
`values`	Partial.<NoInfer.<Properties>>	Values.
`silent`	boolean \| undefined	Update without triggering an event.

un(type, listener) inherited Observable.js, line 173

Unlisten for a certain type of event.

Name	Type	Description
`type`	string \| Array.<string>	The event type or array of event types.
`listener`	function	The listener function.

unset(key, silent) inherited Object.js, line 262

Unsets a property.

Name	Type	Description
`key`	string	Key name.
`silent`	boolean \| undefined	Unset without triggering an event.