OpenLayers

Class: KeyboardZoom

ol/interaction/KeyboardZoom~KeyboardZoom 


import KeyboardZoom from 'ol/interaction/KeyboardZoom';

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 module:ol/Map~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 module:ol/interaction/KeyboardPan~KeyboardPan.

new KeyboardZoom(opt_options)

interaction/KeyboardZoom.js, line 37
Name Type Description
options

Options.

Name Type Description
duration number (defaults to 100)

Animation duration in milliseconds.
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~targetNotEditable.
delta number (defaults to 1)

The zoom level delta on each key press.
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 36

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

dispatchEvent(event){boolean|undefined} inherited

events/Target.js, line 96

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 Object | 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 119

Gets a value.

Name Type Description
key string

Key name.
Returns:
Value.

getActive(){boolean} inherited

interaction/Interaction.js, line 60

Return whether the interaction is currently active.

Returns:
true if the interaction is active, false otherwise.

getKeys(){Array.<string>} inherited

Object.js, line 132

Get a list of object property names.

Returns:
List of property names.

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

interaction/Interaction.js, line 69

Get the map associated with this interaction.

Returns:
Map.

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

Object.js, line 141

Get an object of all property names and values.

Returns:
Object.

getRevision(){number} inherited

Observable.js, line 47

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

Returns:
Revision.

handleEvent(mapBrowserEvent){boolean} inherited

interaction/Interaction.js, line 79

Handles the map browser event.

Name Type Description
mapBrowserEvent module:ol/MapBrowserEvent~MapBrowserEvent

Map browser event.
Returns:
false to stop event propagation.

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

Observable.js, line 60

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 82

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 164

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 89

Activate or deactivate the interaction.

Name Type Description
active boolean

Active.

setProperties(values, opt_silent) inherited

Object.js, line 183

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 101

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 195

Unsets a property.

Name Type Description
key string

Key name.
silent boolean

Unset without triggering an event.