]> git.openstreetmap.org Git - rails.git/blobdiff - vendor/assets/leaflet/leaflet.locate.js
Merge remote-tracking branch 'upstream/pull/2049'
[rails.git] / vendor / assets / leaflet / leaflet.locate.js
index be5c7fc01c95c6129f68e85c0912c91745fb504e..a7e4730b5ab58747c464e22d00973f72346941b2 100644 (file)
-L.Control.Locate = L.Control.extend({
-    options: {
-        position: 'topleft',
-        drawCircle: true,
-        follow: false,  // follow with zoom and pan the user's location
-        // range circle
-        circleStyle: {
-                color: '#136AEC',
-                fillColor: '#136AEC',
-                fillOpacity: 0.15,
-                weight: 2,
-                opacity: 0.5
-            },
-        // inner marker
-        markerStyle: {
-            color: '#136AEC',
-            fillColor: '#2A93EE',
-            fillOpacity: 0.7,
-            weight: 2,
-            opacity: 0.9,
-            radius: 4
-        },
-        metric: true,
-        debug: false,
-        onLocationError: function(err) {
-            alert(err.message);
-        },
-        title: "Show me where I am",
-        popupText: ["You are within ", " from this point"],
-        setView: true, // automatically sets the map view to the user's location
-        locateOptions: {}
-    },
-
-    onAdd: function (map) {
-        var className = 'control-locate',
-            container = L.DomUtil.create('div', className);
-
-        var self = this;
-        this._layer = new L.LayerGroup();
-        this._layer.addTo(map);
-        this._event = undefined;
-        // nested extend so that the first can overwrite the second
-        // and the second can overwrite the third
-        this._locateOptions = L.extend(L.extend({
-            'setView': false // have to set this to false because we have to
-                             // do setView manually
-        }, this.options.locateOptions), {
-            'watch': true  // if you overwrite this, visualization cannot be updated
+/*!
+Copyright (c) 2016 Dominik Moritz
+
+This file is part of the leaflet locate control. It is licensed under the MIT license.
+You can find the project at: https://github.com/domoritz/leaflet-locatecontrol
+*/
+(function (factory, window) {
+     // see https://github.com/Leaflet/Leaflet/blob/master/PLUGIN-GUIDE.md#module-loaders
+     // for details on how to structure a leaflet plugin.
+
+    // define an AMD module that relies on 'leaflet'
+    if (typeof define === 'function' && define.amd) {
+        define(['leaflet'], factory);
+
+    // define a Common JS module that relies on 'leaflet'
+    } else if (typeof exports === 'object') {
+        if (typeof window !== 'undefined' && window.L) {
+            module.exports = factory(L);
+        } else {
+            module.exports = factory(require('leaflet'));
+        }
+    }
+
+    // attach your plugin to the global 'L' variable
+    if (typeof window !== 'undefined' && window.L){
+        window.L.Control.Locate = factory(L);
+    }
+} (function (L) {
+    var LDomUtilApplyClassesMethod = function(method, element, classNames) {
+        classNames = classNames.split(' ');
+        classNames.forEach(function(className) {
+            L.DomUtil[method].call(this, element, className);
         });
+    };
+
+    var addClasses = function(el, names) { LDomUtilApplyClassesMethod('addClass', el, names); };
+    var removeClasses = function(el, names) { LDomUtilApplyClassesMethod('removeClass', el, names); };
+
+    /**
+     * Compatible with L.Circle but a true marker instead of a path
+     */
+    var LocationMarker = L.Marker.extend({
+        initialize: function (latlng, options) {
+            L.Util.setOptions(this, options);
+            this._latlng = latlng;
+            this.createIcon();
+        },
+
+        /**
+         * Create a styled circle location marker
+         */
+        createIcon: function() {
+            var opt = this.options;
+
+            var style = '';
+
+            if (opt.color !== undefined) {
+                style += 'stroke:'+opt.color+';';
+            }
+            if (opt.weight !== undefined) {
+                style += 'stroke-width:'+opt.weight+';';
+            }
+            if (opt.fillColor !== undefined) {
+                style += 'fill:'+opt.fillColor+';';
+            }
+            if (opt.fillOpacity !== undefined) {
+                style += 'fill-opacity:'+opt.fillOpacity+';';
+            }
+            if (opt.opacity !== undefined) {
+                style += 'opacity:'+opt.opacity+';';
+            }
+
+            var icon = this._getIconSVG(opt, style);
+
+            this._locationIcon = L.divIcon({
+                className: icon.className,
+                html: icon.svg,
+                iconSize: [icon.w,icon.h],
+            });
+
+            this.setIcon(this._locationIcon);
+        },
+
+        /**
+         * Return the raw svg for the shape
+         *
+         * Split so can be easily overridden
+         */
+        _getIconSVG: function(options, style) {
+            var r = options.radius;
+            var w = options.weight;
+            var s = r + w;
+            var s2 = s * 2;
+            var svg = '<svg xmlns="http://www.w3.org/2000/svg" width="'+s2+'" height="'+s2+'" version="1.1" viewBox="-'+s+' -'+s+' '+s2+' '+s2+'">' +
+            '<circle r="'+r+'" style="'+style+'" />' +
+            '</svg>';
+            return {
+                className: 'leafet-control-locate-location',
+                svg: svg,
+                w: s2,
+                h: s2
+            };
+        },
 
-        var link = L.DomUtil.create('a', 'control-button', container);
-        link.innerHTML = "<span class='icon geolocate'></span>";
-        link.href = '#';
-        link.title = this.options.title;
+        setStyle: function(style) {
+            L.Util.setOptions(this, style);
+            this.createIcon();
+        }
+    });
+
+    var CompassMarker = LocationMarker.extend({
+        initialize: function (latlng, heading, options) {
+            L.Util.setOptions(this, options);
+            this._latlng = latlng;
+            this._heading = heading;
+            this.createIcon();
+        },
 
-        var _log = function(data) {
-            if (self.options.debug) {
-                console.log(data);
+        setHeading: function(heading) {
+            this._heading = heading;
+        },
+
+        /**
+         * Create a styled arrow compass marker
+         */
+        _getIconSVG: function(options, style) {
+            var r = options.radius;
+            var w = (options.width + options.weight);
+            var h = (r+options.depth + options.weight)*2;
+            var path = 'M0,0 l'+(options.width/2)+','+options.depth+' l-'+(w)+',0 z';
+            var svgstyle = 'transform: rotate('+this._heading+'deg)';
+            var svg = '<svg xmlns="http://www.w3.org/2000/svg" width="'+(w)+'" height="'+h+'" version="1.1" viewBox="-'+(w/2)+' 0 '+w+' '+h+'" style="'+svgstyle+'">'+
+            '<path d="'+path+'" style="'+style+'" />'+
+            '</svg>';
+            return {
+                className: 'leafet-control-locate-heading',
+                svg: svg,
+                w: w,
+                h: h
+            };
+        },
+    });
+
+
+    var LocateControl = L.Control.extend({
+        options: {
+            /** Position of the control */
+            position: 'topleft',
+            /** The layer that the user's location should be drawn on. By default creates a new layer. */
+            layer: undefined,
+            /**
+             * Automatically sets the map view (zoom and pan) to the user's location as it updates.
+             * While the map is following the user's location, the control is in the `following` state,
+             * which changes the style of the control and the circle marker.
+             *
+             * Possible values:
+             *  - false: never updates the map view when location changes.
+             *  - 'once': set the view when the location is first determined
+             *  - 'always': always updates the map view when location changes.
+             *              The map view follows the user's location.
+             *  - 'untilPan': like 'always', except stops updating the
+             *                view if the user has manually panned the map.
+             *                The map view follows the user's location until she pans.
+             *  - 'untilPanOrZoom': (default) like 'always', except stops updating the
+             *                view if the user has manually panned the map.
+             *                The map view follows the user's location until she pans.
+             */
+            setView: 'untilPanOrZoom',
+            /** Keep the current map zoom level when setting the view and only pan. */
+            keepCurrentZoomLevel: false,
+            /** Smooth pan and zoom to the location of the marker. Only works in Leaflet 1.0+. */
+            flyTo: false,
+            /**
+             * The user location can be inside and outside the current view when the user clicks on the
+             * control that is already active. Both cases can be configures separately.
+             * Possible values are:
+             *  - 'setView': zoom and pan to the current location
+             *  - 'stop': stop locating and remove the location marker
+             */
+            clickBehavior: {
+                /** What should happen if the user clicks on the control while the location is within the current view. */
+                inView: 'stop',
+                /** What should happen if the user clicks on the control while the location is outside the current view. */
+                outOfView: 'setView',
+            },
+            /**
+             * If set, save the map bounds just before centering to the user's
+             * location. When control is disabled, set the view back to the
+             * bounds that were saved.
+             */
+            returnToPrevBounds: false,
+            /**
+             * Keep a cache of the location after the user deactivates the control. If set to false, the user has to wait
+             * until the locate API returns a new location before they see where they are again.
+             */
+            cacheLocation: true,
+            /** If set, a circle that shows the location accuracy is drawn. */
+            drawCircle: true,
+            /** If set, the marker at the users' location is drawn. */
+            drawMarker: true,
+            /** If set and supported then show the compass heading */
+            showCompass: true,
+            /** The class to be used to create the marker. For example L.CircleMarker or L.Marker */
+            markerClass: LocationMarker,
+            /** The class us be used to create the compass bearing arrow */
+            compassClass: CompassMarker,
+            /** Accuracy circle style properties. NOTE these styles should match the css animations styles */
+            circleStyle: {
+                className:   'leaflet-control-locate-circle',
+                color:       '#136AEC',
+                fillColor:   '#136AEC',
+                fillOpacity: 0.15,
+                weight:      0
+            },
+            /** Inner marker style properties. Only works if your marker class supports `setStyle`. */
+            markerStyle: {
+                className:   'leaflet-control-locate-marker',
+                color:       '#fff',
+                fillColor:   '#2A93EE',
+                fillOpacity: 1,
+                weight:      3,
+                opacity:     1,
+                radius:      9
+            },
+            /** Compass */
+            compassStyle: {
+                fillColor:   '#2A93EE',
+                fillOpacity: 1,
+                weight:      0,
+                color:       '#fff',
+                opacity:     1,
+                radius:      9, // How far is the arrow is from the center of of the marker
+                width:       9, // Width of the arrow
+                depth:       6  // Length of the arrow
+            },
+            /**
+             * Changes to accuracy circle and inner marker while following.
+             * It is only necessary to provide the properties that should change.
+             */
+            followCircleStyle: {},
+            followMarkerStyle: {
+                // color: '#FFA500',
+                // fillColor: '#FFB000'
+            },
+            followCompassStyle: {},
+            /** The CSS class for the icon. For example fa-location-arrow or fa-map-marker */
+            icon: 'fa fa-map-marker',
+            iconLoading: 'fa fa-spinner fa-spin',
+            /** The element to be created for icons. For example span or i */
+            iconElementTag: 'span',
+            /** Padding around the accuracy circle. */
+            circlePadding: [0, 0],
+            /** Use metric units. */
+            metric: true,
+            /**
+             * This callback can be used in case you would like to override button creation behavior.
+             * This is useful for DOM manipulation frameworks such as angular etc.
+             * This function should return an object with HtmlElement for the button (link property) and the icon (icon property).
+             */
+            createButtonCallback: function (container, options) {
+                var link = L.DomUtil.create('a', 'leaflet-bar-part leaflet-bar-part-single', container);
+                link.title = options.strings.title;
+                var icon = L.DomUtil.create(options.iconElementTag, options.icon, link);
+                return { link: link, icon: icon };
+            },
+            /** This event is called in case of any location error that is not a time out error. */
+            onLocationError: function(err, control) {
+                alert(err.message);
+            },
+            /**
+             * This event is called when the user's location is outside the bounds set on the map.
+             * The event is called repeatedly when the location changes.
+             */
+            onLocationOutsideMapBounds: function(control) {
+                control.stop();
+                alert(control.options.strings.outsideMapBoundsMsg);
+            },
+            /** Display a pop-up when the user click on the inner marker. */
+            showPopup: true,
+            strings: {
+                title: "Show me where I am",
+                metersUnit: "meters",
+                feetUnit: "feet",
+                popup: "You are within {distance} {unit} from this point",
+                outsideMapBoundsMsg: "You seem located outside the boundaries of the map"
+            },
+            /** The default options passed to leaflets locate method. */
+            locateOptions: {
+                maxZoom: Infinity,
+                watch: true,  // if you overwrite this, visualization cannot be updated
+                setView: false // have to set this to false because we have to
+                               // do setView manually
             }
-        };
+        },
 
-        L.DomEvent
-            .on(link, 'click', L.DomEvent.stopPropagation)
-            .on(link, 'click', L.DomEvent.preventDefault)
-            .on(link, 'click', function() {
-                if (self._active && (map.getBounds().contains(self._event.latlng) || !self.options.setView)) {
-                    stopLocate();
+        initialize: function (options) {
+            // set default options if nothing is set (merge one step deep)
+            for (var i in options) {
+                if (typeof this.options[i] === 'object') {
+                    L.extend(this.options[i], options[i]);
                 } else {
-                    if (self.options.setView) {
-                        self._locateOnNextLocationFound = true;
-                    }
-                    if(!self._active) {
-                        map.locate(self._locateOptions);
-                    }
-                    self._active = true;
-                    if (!self._event) {
-                        self._container.className = className + " requesting";
-                    } else {
-                        visualizeLocation();
-                    }
+                    this.options[i] = options[i];
                 }
-            })
-            .on(link, 'dblclick', L.DomEvent.stopPropagation);
+            }
+
+            // extend the follow marker style and circle from the normal style
+            this.options.followMarkerStyle = L.extend({}, this.options.markerStyle, this.options.followMarkerStyle);
+            this.options.followCircleStyle = L.extend({}, this.options.circleStyle, this.options.followCircleStyle);
+            this.options.followCompassStyle = L.extend({}, this.options.compassStyle, this.options.followCompassStyle);
+        },
+
+        /**
+         * Add control to map. Returns the container for the control.
+         */
+        onAdd: function (map) {
+            var container = L.DomUtil.create('div',
+                'leaflet-control-locate leaflet-bar leaflet-control');
+
+            this._layer = this.options.layer || new L.LayerGroup();
+            this._layer.addTo(map);
+            this._event = undefined;
+            this._compassHeading = null;
+            this._prevBounds = null;
 
-        var onLocationFound = function (e) {
-            _log('onLocationFound');
+            var linkAndIcon = this.options.createButtonCallback(container, this.options);
+            this._link = linkAndIcon.link;
+            this._icon = linkAndIcon.icon;
 
-            self._active = true;
+            L.DomEvent
+                .on(this._link, 'click', L.DomEvent.stopPropagation)
+                .on(this._link, 'click', L.DomEvent.preventDefault)
+                .on(this._link, 'click', this._onClick, this)
+                .on(this._link, 'dblclick', L.DomEvent.stopPropagation);
 
-            if (self._event &&
-                (self._event.latlng.lat != e.latlng.lat ||
-                 self._event.latlng.lng != e.latlng.lng)) {
-                _log('location has changed');
+            this._resetVariables();
+
+            this._map.on('unload', this._unload, this);
+
+            return container;
+        },
+
+        /**
+         * This method is called when the user clicks on the control.
+         */
+        _onClick: function() {
+            this._justClicked = true;
+            this._userPanned = false;
+            this._userZoomed = false;
+
+            if (this._active && !this._event) {
+                // click while requesting
+                this.stop();
+            } else if (this._active && this._event !== undefined) {
+                var behavior = this._map.getBounds().contains(this._event.latlng) ?
+                    this.options.clickBehavior.inView : this.options.clickBehavior.outOfView;
+                switch (behavior) {
+                    case 'setView':
+                        this.setView();
+                        break;
+                    case 'stop':
+                        this.stop();
+                        if (this.options.returnToPrevBounds) {
+                            var f = this.options.flyTo ? this._map.flyToBounds : this._map.fitBounds;
+                            f.bind(this._map)(this._prevBounds);
+                        }
+                        break;
+                }
+            } else {
+                if (this.options.returnToPrevBounds) {
+                  this._prevBounds = this._map.getBounds();
+                }
+                this.start();
             }
 
-            self._event = e;
+            this._updateContainerStyle();
+        },
+
+        /**
+         * Starts the plugin:
+         * - activates the engine
+         * - draws the marker (if coordinates available)
+         */
+        start: function() {
+            this._activate();
+
+            if (this._event) {
+                this._drawMarker(this._map);
 
-            if (self.options.follow) {
-                self._locateOnNextLocationFound = true;
+                // if we already have a location but the user clicked on the control
+                if (this.options.setView) {
+                    this.setView();
+                }
             }
+            this._updateContainerStyle();
+        },
+
+        /**
+         * Stops the plugin:
+         * - deactivates the engine
+         * - reinitializes the button
+         * - removes the marker
+         */
+        stop: function() {
+            this._deactivate();
+
+            this._cleanClasses();
+            this._resetVariables();
 
-            visualizeLocation();
-        };
+            this._removeMarker();
+        },
 
-        var visualizeLocation = function() {
-            _log('visualizeLocation,' + 'setView:' + self._locateOnNextLocationFound);
+        /**
+         * This method launches the location engine.
+         * It is called before the marker is updated,
+         * event if it does not mean that the event will be ready.
+         *
+         * Override it if you want to add more functionalities.
+         * It should set the this._active to true and do nothing if
+         * this._active is true.
+         */
+        _activate: function() {
+            if (!this._active) {
+                this._map.locate(this.options.locateOptions);
+                this._active = true;
+
+                // bind event listeners
+                this._map.on('locationfound', this._onLocationFound, this);
+                this._map.on('locationerror', this._onLocationError, this);
+                this._map.on('dragstart', this._onDrag, this);
+                this._map.on('zoomstart', this._onZoom, this);
+                this._map.on('zoomend', this._onZoomEnd, this);
+                if (this.options.showCompass) {
+                    if ('ondeviceorientationabsolute' in window) {
+                        L.DomEvent.on(window, 'deviceorientationabsolute', this._onDeviceOrientation, this);
+                    } else if ('ondeviceorientation' in window) {
+                        L.DomEvent.on(window, 'deviceorientation', this._onDeviceOrientation, this);
+                    }
+                }
+            }
+        },
 
-            var radius = self._event.accuracy / 2;
+        /**
+         * Called to stop the location engine.
+         *
+         * Override it to shutdown any functionalities you added on start.
+         */
+        _deactivate: function() {
+            this._map.stopLocate();
+            this._active = false;
+
+            if (!this.options.cacheLocation) {
+                this._event = undefined;
+            }
 
-            if (self._locateOnNextLocationFound) {
-                map.fitBounds(self._event.bounds);
-                self._locateOnNextLocationFound = false;
+            // unbind event listeners
+            this._map.off('locationfound', this._onLocationFound, this);
+            this._map.off('locationerror', this._onLocationError, this);
+            this._map.off('dragstart', this._onDrag, this);
+            this._map.off('zoomstart', this._onZoom, this);
+            this._map.off('zoomend', this._onZoomEnd, this);
+            if (this.options.showCompass) {
+                this._compassHeading = null;
+                if ('ondeviceorientationabsolute' in window) {
+                    L.DomEvent.off(window, 'deviceorientationabsolute', this._onDeviceOrientation, this);
+                } else if ('ondeviceorientation' in window) {
+                    L.DomEvent.off(window, 'deviceorientation', this._onDeviceOrientation, this);
+                }
             }
+        },
 
-            self._layer.clearLayers();
+        /**
+         * Zoom (unless we should keep the zoom level) and an to the current view.
+         */
+        setView: function() {
+            this._drawMarker();
+            if (this._isOutsideMapBounds()) {
+                this._event = undefined;  // clear the current location so we can get back into the bounds
+                this.options.onLocationOutsideMapBounds(this);
+            } else {
+                if (this.options.keepCurrentZoomLevel) {
+                    var f = this.options.flyTo ? this._map.flyTo : this._map.panTo;
+                    f.bind(this._map)([this._event.latitude, this._event.longitude]);
+                } else {
+                    var f = this.options.flyTo ? this._map.flyToBounds : this._map.fitBounds;
+                    f.bind(this._map)(this._event.bounds, {
+                        padding: this.options.circlePadding,
+                        maxZoom: this.options.locateOptions.maxZoom
+                    });
+                }
+            }
+        },
+
+        /**
+         *
+         */
+        _drawCompass: function() {
+            var latlng = this._event.latlng;
+
+            if (this.options.showCompass && latlng && this._compassHeading !== null) {
+                var cStyle = this._isFollowing() ? this.options.followCompassStyle : this.options.compassStyle;
+                if (!this._compass) {
+                    this._compass = new this.options.compassClass(latlng, this._compassHeading, cStyle).addTo(this._layer);
+                } else {
+                    this._compass.setLatLng(latlng);
+                    this._compass.setHeading(this._compassHeading);
+                    // If the compassClass can be updated with setStyle, update it.
+                    if (this._compass.setStyle) {
+                        this._compass.setStyle(cStyle);
+                    }
+                }
+                // 
+            }
+            if (this._compass && (!this.options.showCompass || this._compassHeading === null)) {
+                this._compass.removeFrom(this._layer);
+                this._compass = null;
+            }
+        },
+
+        /**
+         * Draw the marker and accuracy circle on the map.
+         *
+         * Uses the event retrieved from onLocationFound from the map.
+         */
+        _drawMarker: function() {
+            if (this._event.accuracy === undefined) {
+                this._event.accuracy = 0;
+            }
+
+            var radius = this._event.accuracy;
+            var latlng = this._event.latlng;
 
             // circle with the radius of the location's accuracy
-            if (self.options.drawCircle) {
-                L.circle(self._event.latlng, radius, self.options.circleStyle)
-                    .addTo(self._layer);
+            if (this.options.drawCircle) {
+                var style = this._isFollowing() ? this.options.followCircleStyle : this.options.circleStyle;
+
+                if (!this._circle) {
+                    this._circle = L.circle(latlng, radius, style).addTo(this._layer);
+                } else {
+                    this._circle.setLatLng(latlng).setRadius(radius).setStyle(style);
+                }
             }
 
             var distance, unit;
-            if (self.options.metric) {
+            if (this.options.metric) {
                 distance = radius.toFixed(0);
-                unit = "meters";
+                unit =  this.options.strings.metersUnit;
             } else {
                 distance = (radius * 3.2808399).toFixed(0);
-                unit = "feet";
+                unit = this.options.strings.feetUnit;
             }
 
             // small inner marker
-            var t = self.options.popupText;
-            L.circleMarker(self._event.latlng, self.options.markerStyle)
-                .bindPopup(t[0] + distance + " " + unit  + t[1])
-                .addTo(self._layer);
+            if (this.options.drawMarker) {
+                var mStyle = this._isFollowing() ? this.options.followMarkerStyle : this.options.markerStyle;
+                if (!this._marker) {
+                    this._marker = new this.options.markerClass(latlng, mStyle).addTo(this._layer);
+                } else {
+                    this._marker.setLatLng(latlng);
+                    // If the markerClass can be updated with setStyle, update it.
+                    if (this._marker.setStyle) {
+                        this._marker.setStyle(mStyle);
+                    }
+                }
+            }
+
+            this._drawCompass();
+
+            var t = this.options.strings.popup;
+            if (this.options.showPopup && t && this._marker) {
+                this._marker
+                    .bindPopup(L.Util.template(t, {distance: distance, unit: unit}))
+                    ._popup.setLatLng(latlng);
+            }
+            if (this.options.showPopup && t && this._compass) {
+                this._compass
+                    .bindPopup(L.Util.template(t, {distance: distance, unit: unit}))
+                    ._popup.setLatLng(latlng);
+            }
+        },
+
+        /**
+         * Remove the marker from map.
+         */
+        _removeMarker: function() {
+            this._layer.clearLayers();
+            this._marker = undefined;
+            this._circle = undefined;
+        },
 
-            if (!self._container)
+        /**
+         * Unload the plugin and all event listeners.
+         * Kind of the opposite of onAdd.
+         */
+        _unload: function() {
+            this.stop();
+            this._map.off('unload', this._unload, this);
+        },
+
+        /**
+         * Sets the compass heading
+         */
+        _setCompassHeading: function(angle) {
+            if (!isNaN(parseFloat(angle)) && isFinite(angle)) {
+                angle = Math.round(angle);
+
+                this._compassHeading = angle;
+                L.Util.requestAnimFrame(this._drawCompass, this);
+            } else {
+                this._compassHeading = null;
+            }
+        },
+
+        /**
+         * If the compass fails calibration just fail safely and remove the compass
+         */
+        _onCompassNeedsCalibration: function() {
+            this._setCompassHeading();
+        },
+
+        /**
+         * Process and normalise compass events
+         */
+        _onDeviceOrientation: function(e) {
+            if (!this._active) {
                 return;
-            self._container.className = className + " active";
-        };
+            }
 
-        var resetVariables = function() {
-            self._active = false;
-            self._locateOnNextLocationFound = true;
-        };
+            if (e.webkitCompassHeading) {
+                // iOS
+                this._setCompassHeading(e.webkitCompassHeading);
+            } else if (e.absolute && e.alpha) {
+                // Android
+                this._setCompassHeading(360 - e.alpha)
+            }
+        },
 
-        resetVariables();
+        /**
+         * Calls deactivate and dispatches an error.
+         */
+        _onLocationError: function(err) {
+            // ignore time out error if the location is watched
+            if (err.code == 3 && this.options.locateOptions.watch) {
+                return;
+            }
 
-        var stopLocate = function() {
-            _log('stopLocate');
-            map.stopLocate();
+            this.stop();
+            this.options.onLocationError(err, this);
+        },
 
-            self._container.className = className;
-            resetVariables();
+        /**
+         * Stores the received event and updates the marker.
+         */
+        _onLocationFound: function(e) {
+            // no need to do anything if the location has not changed
+            if (this._event &&
+                (this._event.latlng.lat === e.latlng.lat &&
+                 this._event.latlng.lng === e.latlng.lng &&
+                     this._event.accuracy === e.accuracy)) {
+                return;
+            }
 
-            self._layer.clearLayers();
-        };
+            if (!this._active) {
+                // we may have a stray event
+                return;
+            }
 
+            this._event = e;
 
-        var onLocationError = function (err) {
-            _log('onLocationError');
+            this._drawMarker();
+            this._updateContainerStyle();
 
-            // ignore timeout error if the location is watched
-            if (err.code==3 && this._locateOptions.watch) {
+            switch (this.options.setView) {
+                case 'once':
+                    if (this._justClicked) {
+                        this.setView();
+                    }
+                    break;
+                case 'untilPan':
+                    if (!this._userPanned) {
+                        this.setView();
+                    }
+                    break;
+                case 'untilPanOrZoom':
+                    if (!this._userPanned && !this._userZoomed) {
+                        this.setView();
+                    }
+                    break;
+                case 'always':
+                    this.setView();
+                    break;
+                case false:
+                    // don't set the view
+                    break;
+            }
+
+            this._justClicked = false;
+        },
+
+        /**
+         * When the user drags. Need a separate event so we can bind and unbind event listeners.
+         */
+        _onDrag: function() {
+            // only react to drags once we have a location
+            if (this._event) {
+                this._userPanned = true;
+                this._updateContainerStyle();
+                this._drawMarker();
+            }
+        },
+
+        /**
+         * When the user zooms. Need a separate event so we can bind and unbind event listeners.
+         */
+        _onZoom: function() {
+            // only react to drags once we have a location
+            if (this._event) {
+                this._userZoomed = true;
+                this._updateContainerStyle();
+                this._drawMarker();
+            }
+        },
+
+        /**
+         * After a zoom ends update the compass
+         */
+        _onZoomEnd: function() {
+            if (this._event) {
+                this._drawCompass();
+            }
+        },
+
+        /**
+         * Compute whether the map is following the user location with pan and zoom.
+         */
+        _isFollowing: function() {
+            if (!this._active) {
+                return false;
+            }
+
+            if (this.options.setView === 'always') {
+                return true;
+            } else if (this.options.setView === 'untilPan') {
+                return !this._userPanned;
+            } else if (this.options.setView === 'untilPanOrZoom') {
+                return !this._userPanned && !this._userZoomed;
+            }
+        },
+
+        /**
+         * Check if location is in map bounds
+         */
+        _isOutsideMapBounds: function() {
+            if (this._event === undefined) {
+                return false;
+            }
+            return this._map.options.maxBounds &&
+                !this._map.options.maxBounds.contains(this._event.latlng);
+        },
+
+        /**
+         * Toggles button class between following and active.
+         */
+        _updateContainerStyle: function() {
+            if (!this._container) {
                 return;
             }
 
-            stopLocate();
-            self.options.onLocationError(err);
-        };
+            if (this._active && !this._event) {
+                // active but don't have a location yet
+                this._setClasses('requesting');
+            } else if (this._isFollowing()) {
+                this._setClasses('following');
+            } else if (this._active) {
+                this._setClasses('active');
+            } else {
+                this._cleanClasses();
+            }
+        },
+
+        /**
+         * Sets the CSS classes for the state.
+         */
+        _setClasses: function(state) {
+            if (state == 'requesting') {
+                removeClasses(this._container, "active following");
+                addClasses(this._container, "requesting");
+
+                removeClasses(this._icon, this.options.icon);
+                addClasses(this._icon, this.options.iconLoading);
+            } else if (state == 'active') {
+                removeClasses(this._container, "requesting following");
+                addClasses(this._container, "active");
+
+                removeClasses(this._icon, this.options.iconLoading);
+                addClasses(this._icon, this.options.icon);
+            } else if (state == 'following') {
+                removeClasses(this._container, "requesting");
+                addClasses(this._container, "active following");
+
+                removeClasses(this._icon, this.options.iconLoading);
+                addClasses(this._icon, this.options.icon);
+            }
+        },
+
+        /**
+         * Removes all classes from button.
+         */
+        _cleanClasses: function() {
+            L.DomUtil.removeClass(this._container, "requesting");
+            L.DomUtil.removeClass(this._container, "active");
+            L.DomUtil.removeClass(this._container, "following");
 
-        // event hooks
-        map.on('locationfound', onLocationFound, self);
-        map.on('locationerror', onLocationError, self);
+            removeClasses(this._icon, this.options.iconLoading);
+            addClasses(this._icon, this.options.icon);
+        },
 
-        return container;
-    }
-});
+        /**
+         * Reinitializes state variables.
+         */
+        _resetVariables: function() {
+            // whether locate is active or not
+            this._active = false;
 
-L.Map.addInitHook(function () {
-    if (this.options.locateControl) {
-        this.locateControl = L.control.locate();
-        this.addControl(this.locateControl);
-    }
-});
+            // true if the control was clicked for the first time
+            // we need this so we can pan and zoom once we have the location
+            this._justClicked = false;
+
+            // true if the user has panned the map after clicking the control
+            this._userPanned = false;
+
+            // true if the user has zoomed the map after clicking the control
+            this._userZoomed = false;
+        }
+    });
+
+    L.control.locate = function (options) {
+        return new L.Control.Locate(options);
+    };
 
-L.control.locate = function (options) {
-    return new L.Control.Locate(options);
-};
+    return LocateControl;
+}, window));