For a plugin that handles fullscreen exclusively see Leaflet.fullscreen.

This is a simple extension of Leaflet.Control.Zoom that adds a fullscreen button above the zoom in and zoom out controls.

You can make a Leaflet map fullscreen programatically by changing the CSS of the map container. This extension simply integrates that functionality into the Leaflet interface.

Be sure to include the leaflet.zoomfs.js script somewhere after Leaflet is loaded.

<script src="http://cdn.leafletjs.com/leaflet-0.5.1/leaflet.js"></script>
<script src="leaflet.zoomfs.js"></script>

Do all your normal Leaflet initialization stuff, except make sure that you initialize the map without the default zoom controls:

<!-- map container -->
<div id="map"></div>

// init map
var map = new L.Map('map', { zoomControl:false });

Then, instantiate the ZoomFS control and add it to the map:

var zoomFS = new L.Control.ZoomFS(); 
map.addControl(zoomFS);

There are 2 events you can bind to: enterFullscreen and exitFullscreen. Note that these events are triggered on the Map object; not ZoomFS.

map.on('enterFullscreen', function(){
  if(window.console) window.console.log('enterFullscreen');
});

map.on('exitFullscreen', function(){
  if(window.console) window.console.log('exitFullscreen');
});

This extension applies the following inline styles to make the map fullscreen. We also apply a class of leaflet-fullscreen to the map container.

<div id="map" class="leaflet-container leaflet-fullscreen" style="position: fixed; left: 0px; top: 0px; width: 100%; height: 100%;">

No style is applied to the fullscreen button itself. Basic style is handled internally by Leaflet.Control.Zoom, but you'll need to add your own button style:

.leaflet-control-fullscreen {
  background-image: url(your/amazing/icon.png);
}

All inline style on your map container will be removed when exitFullscreen is triggered. position:relative is re-applied automatically if you do not have a position declared in your base styles (as this is required by Leaflet). A height is required by Leaflet core, and it should be declared in your base CSS (not inline) like so:

#map {
  position: relative;
  height: 400px;
}

• This extension was built and tested for Leaflet version 0.5.1. If you need this to work with Leaflet 0.4.4 or Leaflet 0.3.1 there are old versions in tags
• If you want the fullscreen button below the zoom in and zoom out buttons simply switch the order in which the controls are added in leaflet.zoomfs.js.