ol3-google-maps/examples/layerswitcher.js

OpenLayers 3 Google Maps integration library

var center = [-7908084, 6177492];

// This dummy layer tells Google Maps to switch to its default map type
var googleLayer = new olgm.layer.Google({
  title: 'Google',
  type: 'base'
});

var osmLayer = new ol.layer.Tile({
  source: new ol.source.OSM(),
  title: 'OSM',
  type: 'base'
});


var map = new ol.Map({
  // use OL3-Google-Maps recommended default interactions
  interactions: olgm.interaction.defaults(),
  layers: [
    googleLayer,
    osmLayer
  ],
  target: 'map',
  view: new ol.View({
    center: center,
    zoom: 12
  })
});

var olGM = new olgm.OLGoogleMaps({map: map}); // map is the ol.Map instance
olGM.activate();

var layerSwitcher = new ol.control.LayerSwitcher();
map.addControl(layerSwitcher);