OpenLayers 3 API Documentation

Class: KeyboardZoom

ol.interaction. KeyboardZoom

experimental new ol.interaction.KeyboardZoom(opt_options)

src/ol/interaction/keyboardzoominteraction.js, line 28

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 ol.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 ol.interaction.KeyboardPan.

Name Type Argument Description
options optional

Options.

Name Type Description
duration number | undefined

Animation duration in milliseconds. Default is 100.
condition ol.events.ConditionType | undefined

A conditional modifier (i.e. Shift key) that determines if the interaction is active or not, default is no modifiers.
delta number | undefined

The amount to zoom on each key press. Default is 1.
Fires:
  • change

Extends

Methods

experimental inherited dispatchChangeEvent()

src/ol/observable.js, line 39

Dispatches a change event. Register a listener for this event to get notified of changes.

Fires:
  • change

experimental inherited on(type, listener, opt_this){goog.events.Key}

src/ol/observable.js, line 61

Listen for a certain type of event.

Name Type Argument Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object <optional>
 optional

The object to use as this in listener.
Returns:
key for the listener.

experimental inherited once(type, listener, opt_this){goog.events.Key}

src/ol/observable.js, line 74

Listen once for a certain type of event.

Name Type Argument Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object <optional>
 optional

The object to use as this in listener.
Returns:
key for the listener.

experimental inherited un(type, listener, opt_this)

src/ol/observable.js, line 86

Unlisten for a certain type of event.

Name Type Argument Description
type string | Array.<string>

The event type or array of event types.
listener function

The listener function.
this Object <optional>
 optional

The object to use as this in listener.

experimental inherited unByKey(key)

src/ol/observable.js, line 96

Removes an event listener using the key returned by on() or once().

Name Type Description
key goog.events.Key

Key.