OpenLayers 3

Class: Map

ol.Map

The map is the core component of OpenLayers. For a map to render, a view, one or more layers, and a target container are needed:

var map = new ol.Map({
  view: new ol.View({
    center: [0, 0],
    zoom: 1
  }),
  layers: [
    new ol.layer.Tile({
      source: new ol.source.OSM()
    })
  ],
  target: 'map'
});

The above snippet creates a map using a ol.layer.Tile to display ol.source.OSM OSM data and render it to a DOM element with the id map.

The constructor places a viewport container (with CSS class name ol-viewport) in the target element (see getViewport()), and then two further elements within the viewport: one with CSS class name ol-overlaycontainer-stopevent for controls and some overlays, and one with CSS class name ol-overlaycontainer for other overlays (see the stopEvent option of ol.Overlay for the difference). The map itself is placed in a further element within the viewport.

Layers are stored as a ol.Collection in layerGroups. A top-level group is provided by the library. This is what is accessed by getLayerGroup and setLayerGroup. Layers entered in the options are added to this group, and addLayer and removeLayer change the layer collection in the group. getLayers is a convenience function for getLayerGroup().getLayers(). Note that ol.layer.Group is a subclass of ol.layer.Base, so layers entered in the options or added with addLayer can be groups, which can contain further groups, and so on.

new ol.Map(options)

src/ol/map.js, line 146
Name Type Description
options

Map options.

Name Type Description
controls ol.Collection.<ol.control.Control> | Array.<ol.control.Control> | undefined

Controls initially added to the map. If not specified, ol.control.defaults() is used.
pixelRatio number | undefined experimental

The ratio between physical pixels and device-independent pixels (dips) on the device. If undefined then it gets set by using window.devicePixelRatio.
interactions ol.Collection.<ol.interaction.Interaction> | Array.<ol.interaction.Interaction> | undefined

Interactions that are initially added to the map. If not specified, ol.interaction.defaults() is used.
keyboardEventTarget Element | Document | string | undefined experimental

The element to listen to keyboard events on. This determines when the KeyboardPan and KeyboardZoom interactions trigger. For example, if this option is set to document the keyboard interactions will always trigger. If this option is not specified, the element the library listens to keyboard events on is the map target (i.e. the user-provided div for the map). If this is not document the target element needs to be focused for key events to be emitted, requiring that the target element has a tabindex attribute.
layers Array.<ol.layer.Base> | ol.Collection.<ol.layer.Base> | undefined

Layers. If this is not defined, a map with no layers will be rendered. Note that layers are rendered in the order supplied, so if you want, for example, a vector layer to appear on top of a tile layer, it must come after the tile layer.
loadTilesWhileAnimating boolean | undefined experimental

When set to true, tiles will be loaded during animations. This may improve the user experience, but can also make animations stutter on devices with slow memory. Default is false.
loadTilesWhileInteracting boolean | undefined experimental

When set to true, tiles will be loaded while interacting with the map. This may improve the user experience, but can also make map panning and zooming choppy on devices with slow memory. Default is false.
logo boolean | string | olx.LogoOptions | Element | undefined

The map logo. A logo to be displayed on the map at all times. If a string is provided, it will be set as the image source of the logo. If an object is provided, the src property should be the URL for an image and the href property should be a URL for creating a link. If an element is provided, the element will be used. To disable the map logo, set the option to false. By default, the OpenLayers 3 logo is shown.
overlays ol.Collection.<ol.Overlay> | Array.<ol.Overlay> | undefined

Overlays initially added to the map. By default, no overlays are added.
renderer ol.RendererType | Array.<(ol.RendererType|string)> | string | undefined

Renderer. By default, Canvas and WebGL renderers are tested for support in that order, and the first supported used. Specify a ol.RendererType here to use a specific renderer. Note that the Canvas renderer fully supports vector data, but WebGL can only render Point geometries.
target Element | string | undefined

The container for the map, either the element itself or the id of the element. If not specified at construction time, ol.Map#setTarget must be called for the map to be rendered.
view ol.View | undefined

The map's view. No layer sources will be fetched unless this is specified at construction time or through ol.Map#setView.
Fires:

Extends

Observable Properties

Name Type Settable ol.ObjectEvent type Description
layerGroup ol.layer.Group yes change:layergroup

A layer group containing the layers in this map.
size ol.Size | undefined yes change:size

The size in pixels of the map in the DOM.
target Element | string | undefined yes change:target

The Element or id of the Element that the map is rendered in.
view ol.View yes change:view

The view that controls this map.

Methods

addControl(control)

src/ol/map.js, line 474

Add the given control to the map.

Name Type Description
control ol.control.Control

Control.

addInteraction(interaction)

src/ol/map.js, line 484

Add the given interaction to the map.

Name Type Description
interaction ol.interaction.Interaction

Interaction to add.

addLayer(layer)

src/ol/map.js, line 496

Adds the given layer to the top of this map. If you want to add a layer elsewhere in the stack, use getLayers() and the methods available on ol.Collection.

Name Type Description
layer ol.layer.Base

Layer.

addOverlay(overlay)

src/ol/map.js, line 507

Add the given overlay to the map.

Name Type Description
overlay ol.Overlay

Overlay.

beforeRender(var_args) experimental

src/ol/map.js, line 533

Add functions to be called before rendering. This can be used for attaching animations before updating the map's view. The ol.animation namespace provides several static methods for creating prerender functions.

Name Type Description
var_args ol.PreRenderFunction

Any number of pre-render functions.

changed() inherited experimental

src/ol/observable.js, line 58

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

dispatchEvent(event) inherited experimental

src/ol/observable.js, line 75

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 | ol.events.Event | string

Event object.

forEachFeatureAtPixel(pixel, callback, opt_this, opt_layerFilter, opt_this2){T|undefined}

src/ol/map.js, line 599

Detect features that intersect a pixel on the viewport, and execute a callback with each intersecting feature. Layers included in the detection can be configured through opt_layerFilter.

Name Type Description
pixel ol.Pixel

Pixel.
callback function

Feature callback. The callback will be called with two arguments. The first argument is one feature or render feature at the pixel, the second is the layer of the feature and will be null for unmanaged layers. To stop detection, callback functions can return a truthy value.
this S

Value to use as this when executing callback.
layerFilter function

Layer filter function. The filter function will receive one argument, the layer-candidate and it should return a boolean value. Only layers which are visible and for which this function returns true will be tested for features. By default, all visible layers will be tested.
this2 U

Value to use as this when executing layerFilter.
Returns:
Callback result, i.e. the return value of last callback execution, or the first truthy callback return value.

forEachLayerAtPixel(pixel, callback, opt_this, opt_layerFilter, opt_this2){T|undefined}

src/ol/map.js, line 637

Detect layers that have a color value at a pixel on the viewport, and execute a callback with each matching layer. Layers included in the detection can be configured through opt_layerFilter.

Name Type Description
pixel ol.Pixel

Pixel.
callback function

Layer callback. This callback will recieve two arguments: first is the layer, second argument is ol.Color and will be null for layer types that do not currently support this argument. To stop detection callback functions can return a truthy value.
this S

Value to use as this when executing callback.
layerFilter function

Layer filter function. The filter function will receive one argument, the layer-candidate and it should return a boolean value. Only layers which are visible and for which this function returns true will be tested for features. By default, all visible layers will be tested.
this2 U

Value to use as this when executing layerFilter.
Returns:
Callback result, i.e. the return value of last callback execution, or the first truthy callback return value.

get(key){*} inherited

src/ol/object.js, line 148

Gets a value.

Name Type Description
key string

Key name.
Returns:
Value.

getControls(){ol.Collection.<ol.control.Control>}

src/ol/map.js, line 763

Get the map controls. Modifying this collection changes the controls associated with the map.

Returns:
Controls.

getCoordinateFromPixel(pixel){ol.Coordinate}

src/ol/map.js, line 747

Get the coordinate for a given pixel. This returns a coordinate in the map view projection.

Name Type Description
pixel ol.Pixel

Pixel position in the map viewport.
Returns:
The coordinate for the pixel position.

getEventCoordinate(event){ol.Coordinate}

src/ol/map.js, line 685

Returns the geographical coordinate for a browser event.

Name Type Description
event Event

Event.
Returns:
Coordinate.

getEventPixel(event){ol.Pixel}

src/ol/map.js, line 696

Returns the map pixel position for a browser event relative to the viewport.

Name Type Description
event Event

Event.
Returns:
Pixel.

getInteractions(){ol.Collection.<ol.interaction.Interaction>}

src/ol/map.js, line 801

Get the map interactions. Modifying this collection changes the interactions associated with the map.

Interactions are used for e.g. pan, zoom and rotate.

Returns:
Interactions.

getKeys(){Array.<string>} inherited

src/ol/object.js, line 162

Get a list of object property names.

Returns:
List of property names.

getLayerGroup(){ol.layer.Group}

src/ol/map.js, line 812

Get the layergroup associated with this map.

Returns:
A layer group containing the layers in this map.

getLayers(){ol.Collection.<ol.layer.Base>}

src/ol/map.js, line 822

Get the collection of layers associated with this map.

Returns:
Layers.

getOverlayById(id){ol.Overlay} experimental

src/ol/map.js, line 787

Get an overlay by its identifier (the value returned by overlay.getId()). Note that the index treats string and numeric identifiers as the same. So map.getOverlayById(2) will return an overlay with id '2' or 2.

Name Type Description
id string | number

Overlay identifier.
Returns:
Overlay.

getOverlays(){ol.Collection.<ol.Overlay>}

src/ol/map.js, line 774

Get the map overlays. Modifying this collection changes the overlays associated with the map.

Returns:
Overlays.

getPixelFromCoordinate(coordinate){ol.Pixel}

src/ol/map.js, line 835

Get the pixel for a coordinate. This takes a coordinate in the map view projection and returns the corresponding pixel.

Name Type Description
coordinate ol.Coordinate

A map coordinate.
Returns:
A pixel position in the map viewport.

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

src/ol/object.js, line 172

Get an object of all property names and values.

Returns:
Object.

getRevision(){number} inherited experimental

src/ol/observable.js, line 84

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

Returns:
Revision.

getSize(){ol.Size|undefined}

src/ol/map.js, line 861

Get the size of this map.

Returns:
The size in pixels of the map in the DOM.

getTarget(){Element|string|undefined}

src/ol/map.js, line 715

Get the target in which this map is rendered. Note that this returns what is entered as an option or in setTarget: if that was an element, it returns an element; if a string, it returns that.

Returns:
The Element or id of the Element that the map is rendered in.

getTargetElement(){Element} experimental

src/ol/map.js, line 728

Get the DOM element into which this map is rendered. In contrast to getTarget this method always return an Element, or null if the map has no target.

Returns:
The element that the map is rendered in.

getView(){ol.View}

src/ol/map.js, line 873

Get the view associated with this map. A view manages properties such as center and resolution.

Returns:
The view that controls this map.

getViewport(){Element}

src/ol/map.js, line 883

Get the element that serves as the map viewport.

Returns:
Viewport.

hasFeatureAtPixel(pixel, opt_layerFilter, opt_this){boolean} experimental

src/ol/map.js, line 666

Detect if features intersect a pixel on the viewport. Layers included in the detection can be configured through opt_layerFilter.

Name Type Description
pixel ol.Pixel

Pixel.
layerFilter function

Layer filter function. The filter function will receive one argument, the layer-candidate and it should return a boolean value. Only layers which are visible and for which this function returns true will be tested for features. By default, all visible layers will be tested.
this U

Value to use as this when executing layerFilter.
Returns:
Is there a feature at the given pixel?

on(type, listener, opt_this){ol.EventsKey|Array.<ol.EventsKey>} inherited

src/ol/observable.js, line 99

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.
this Object

The object to use as this in listener.
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, opt_this){ol.EventsKey|Array.<ol.EventsKey>} inherited

src/ol/observable.js, line 124

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.
this Object

The object to use as this in listener.
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.

removeControl(control){ol.control.Control|undefined}

src/ol/map.js, line 1186

Remove the given control from the map.

Name Type Description
control ol.control.Control

Control.
Returns:
The removed control (or undefined if the control was not found).

removeInteraction(interaction){ol.interaction.Interaction|undefined}

src/ol/map.js, line 1198

Remove the given interaction from the map.

Name Type Description
interaction ol.interaction.Interaction

Interaction to remove.
Returns:
The removed interaction (or undefined if the interaction was not found).

removeLayer(layer){ol.layer.Base|undefined}

src/ol/map.js, line 1210

Removes the given layer from the map.

Name Type Description
layer ol.layer.Base

Layer.
Returns:
The removed layer (or undefined if the layer was not found).

removeOverlay(overlay){ol.Overlay|undefined}

src/ol/map.js, line 1223

Remove the given overlay from the map.

Name Type Description
overlay ol.Overlay

Overlay.
Returns:
The removed overlay (or undefined if the overlay was not found).

render()

src/ol/map.js, line 1171

Request a map rendering (at the next animation frame).

renderSync()

src/ol/map.js, line 1159

Requests an immediate render in a synchronous manner.

set(key, value, opt_silent) inherited

src/ol/object.js, line 197

Sets a value.

Name Type Description
key string

Key name.
value *

Value.
silent boolean

Update without triggering an event.

setLayerGroup(layerGroup)

src/ol/map.js, line 1325

Sets the layergroup of this map.

Name Type Description
layerGroup ol.layer.Group

A layer group containing the layers in this map.

setProperties(values, opt_silent) inherited

src/ol/object.js, line 217

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.

setSize(size) experimental

src/ol/map.js, line 1336

Set the size of this map.

Name Type Description
size ol.Size | undefined

The size in pixels of the map in the DOM.

setTarget(target)

src/ol/map.js, line 1348

Set the target element to render this map into.

Name Type Description
target Element | string | undefined

The Element or id of the Element that the map is rendered in.

setView(view)

src/ol/map.js, line 1359

Set the view for this map.

Name Type Description
view ol.View

The view that controls this map.

un(type, listener, opt_this) inherited

src/ol/observable.js, line 147

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.
this Object

The object which was used as this by the listener.

unByKey(key) inherited

src/ol/observable.js, line 168

Removes an event listener using the key returned by on() or once(). Note that using the ol.Observable.unByKey static function is to be preferred.

Name Type Description
key ol.EventsKey | Array.<ol.EventsKey>

The key returned by on() or once() (or an array of keys).

unset(key, opt_silent) inherited

src/ol/object.js, line 231

Unsets a property.

Name Type Description
key string

Key name.
silent boolean

Unset without triggering an event.

updateSize()

src/ol/map.js, line 1379

Force a recalculation of the map viewport size. This should be called when third-party code changes the size of the map viewport.