DragZoom~DragZoom

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

Allows the user to zoom the map by clicking and dragging on the map, normally combined with a ol/events/condition that limits it to when a key, shift by default, is held down.

To change the style of the box, use CSS and the .ol-dragzoom selector, or your custom one configured with className.

new DragZoom(options) interaction/DragZoom.js, line 32

Name	Type	Description
`className`	string (defaults to 'ol-dragzoom')	CSS class name for styling the box.
`condition`	Condition \| undefined	A function that takes a `MapBrowserEvent` and returns a boolean to indicate whether that event should be handled. Default is `shiftKeyOnly`.
`duration`	number (defaults to 200)	Animation duration in milliseconds.
`out`	boolean (defaults to false)	Use interaction for zooming out.
`minArea`	number (defaults to 64)	The minimum area of the box in pixel, this value is used by the parent default `boxEndCondition` function.

Fires:

boxcancel (DragBoxEvent) - Triggered upon drag box canceled.
boxdrag (DragBoxEvent) - Triggered on drag when box is active.
boxend (DragBoxEvent) - Triggered upon drag box end.
boxstart (DragBoxEvent) - Triggered upon drag box start.
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

DragBox

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.

getGeometry(){Polygon} inherited interaction/DragBox.js, line 198

Returns geometry of last drawn box.

Returns:

Geometry.

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.

getPointerCount(){number} inherited interaction/Pointer.js, line 95

Returns the current number of pointers involved in the interaction, e.g. 2 when two fingers are used.

Returns:

The number of pointers.

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.

handleEvent(mapBrowserEvent){boolean} inherited interaction/Pointer.js, line 125

Handles the map browser event and may call into other functions, if event sequences like e.g. 'drag' or 'down-up' etc. are detected.

Name	Type	Description
`mapBrowserEvent`	MapBrowserEvent	Map browser event.

Returns:

false to stop event propagation.

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/DragBox.js, line 292

Activate or deactivate the interaction.

Name	Type	Description
`active`	boolean	Active.

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.