leaflet/src/map/ext/Map.Geolocation.js

JavaScript library for mobile-friendly interactive maps

/*
 * Provides L.Map with convenient shortcuts for using browser geolocation features.
 */

// @namespace Map

L.Map.include({
	// @section Geolocation methods
	_defaultLocateOptions: {
		timeout: 10000,
		watch: false
		// setView: false
		// maxZoom: <Number>
		// maximumAge: 0
		// enableHighAccuracy: false
	},

	// @method locate(options?: Locate options): this
	// Tries to locate the user using the Geolocation API, firing a [`locationfound`](#map-locationfound)
	// event with location data on success or a [`locationerror`](#map-locationerror) event on failure,
	// and optionally sets the map view to the user's location with respect to
	// detection accuracy (or to the world view if geolocation failed).
	// Note that, if your page doesn't use HTTPS, this method will fail in
	// modern browsers ([Chrome 50 and newer](https://sites.google.com/a/chromium.org/dev/Home/chromium-security/deprecating-powerful-features-on-insecure-origins))
	// See `Locate options` for more details.
	locate: function (options) {

		options = this._locateOptions = L.extend({}, this._defaultLocateOptions, options);

		if (!('geolocation' in navigator)) {
			this._handleGeolocationError({
				code: 0,
				message: 'Geolocation not supported.'
			});
			return this;
		}

		var onResponse = L.bind(this._handleGeolocationResponse, this),
		    onError = L.bind(this._handleGeolocationError, this);

		if (options.watch) {
			this._locationWatchId =
			        navigator.geolocation.watchPosition(onResponse, onError, options);
		} else {
			navigator.geolocation.getCurrentPosition(onResponse, onError, options);
		}
		return this;
	},

	// @method stopLocate(): this
	// Stops watching location previously initiated by `map.locate({watch: true})`
	// and aborts resetting the map view if map.locate was called with
	// `{setView: true}`.
	stopLocate: function () {
		if (navigator.geolocation && navigator.geolocation.clearWatch) {
			navigator.geolocation.clearWatch(this._locationWatchId);
		}
		if (this._locateOptions) {
			this._locateOptions.setView = false;
		}
		return this;
	},

	_handleGeolocationError: function (error) {
		var c = error.code,
		    message = error.message ||
		            (c === 1 ? 'permission denied' :
		            (c === 2 ? 'position unavailable' : 'timeout'));

		if (this._locateOptions.setView && !this._loaded) {
			this.fitWorld();
		}

		// @section Location events
		// @event locationerror: ErrorEvent
		// Fired when geolocation (using the [`locate`](#map-locate) method) failed.
		this.fire('locationerror', {
			code: c,
			message: 'Geolocation error: ' + message + '.'
		});
	},

	_handleGeolocationResponse: function (pos) {
		var lat = pos.coords.latitude,
		    lng = pos.coords.longitude,
		    latlng = new L.LatLng(lat, lng),
		    bounds = latlng.toBounds(pos.coords.accuracy),
		    options = this._locateOptions;

		if (options.setView) {
			var zoom = this.getBoundsZoom(bounds);
			this.setView(latlng, options.maxZoom ? Math.min(zoom, options.maxZoom) : zoom);
		}

		var data = {
			latlng: latlng,
			bounds: bounds,
			timestamp: pos.timestamp
		};

		for (var i in pos.coords) {
			if (typeof pos.coords[i] === 'number') {
				data[i] = pos.coords[i];
			}
		}

		// @event locationfound: LocationEvent
		// Fired when geolocation (using the [`locate`](#map-locate) method)
		// went successfully.
		this.fire('locationfound', data);
	}
});