Class: MouseWheelZoom

ol/interaction/MouseWheelZoom~MouseWheelZoom 


import MouseWheelZoom from 'ol/interaction/MouseWheelZoom';

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

new MouseWheelZoom(opt_options)

interaction/MouseWheelZoom.js, line 42
Name Type Description
options

Options.

Name Type Description
condition module:ol/events/condition~Condition

A function that takes an module:ol/MapBrowserEvent~MapBrowserEvent and returns a boolean to indicate whether that event should be handled. Default is module:ol/events/condition.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:

Extends

Observable Properties

Name Type Settable ol/Object.ObjectEvent type Description
active boolean yes change:active

true if the interaction is active, false otherwise.

Methods

changed() inherited

Observable.js, line 70

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 module:ol/events/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 135

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 148

Get a list of object property names.

Returns:
List of property names.

getMap(){module:ol/PluggableMap~PluggableMap} inherited

interaction/Interaction.js, line 91

Get the map associated with this interaction.

Returns:
Map.

getProperties(){Object.<string, *>} inherited

Object.js, line 157

Get an object of all property names and values.

Returns:
Object.

getRevision(){number} inherited

Observable.js, line 81

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

Returns:
Revision.

on(type, listener){module:ol/events~EventsKey|Array.<module:ol/events~EventsKey>} inherited

Observable.js, line 155

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){module:ol/events~EventsKey|Array.<module:ol/events~EventsKey>} inherited

Observable.js, line 167

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, opt_silent) inherited

Object.js, line 203

Sets a value.

Name Type Description
key string

Key name.
value *

Value.
silent boolean

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 289

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, opt_silent) inherited

Object.js, line 223

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 Object.<string, *>

Values.
silent boolean

Update without triggering an event.

un(type, listener) inherited

Observable.js, line 176

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, opt_silent) inherited

Object.js, line 247

Unsets a property.

Name Type Description
key string

Key name.
silent boolean

Unset without triggering an event.