Class: KeyboardZoom

ol/interaction/KeyboardZoom~KeyboardZoom 


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

Allows the user to zoom the map using keyboard + and -. Note that, although this interaction is by default included in maps, the keys can only be used when browser focus is on the element to which the keyboard events are attached. By default, this is the map div, though you can change this with the keyboardEventTarget in Map. document never loses focus but, for any other element, focus will have to be on, and returned to, this element if the keys are to function. See also KeyboardPan.

new KeyboardZoom(options)

interaction/KeyboardZoom.js, line 31
Name Type Description
duration number (defaults to 100)

Animation duration in milliseconds.
condition Condition | undefined

A function that takes an MapBrowserEvent and returns a boolean to indicate whether that event should be handled. Default is targetNotEditable.
delta number (defaults to 1)

The zoom level delta on each key press.
Fires:

Extends

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 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(){Map | null} 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 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 207

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.

setProperties(values, silent) inherited

Object.js, line 227

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 | 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 251

Unsets a property.

Name Type Description
key string

Key name.
silent boolean | undefined

Unset without triggering an event.