Files
openlayers/src/ol/Geolocation.js
2018-07-19 08:37:32 -06:00

336 lines
9.3 KiB
JavaScript

/**
* @module ol/Geolocation
*/
import GeolocationProperty from './GeolocationProperty.js';
import BaseObject, {getChangeEventType} from './Object.js';
import {listen} from './events.js';
import EventType from './events/EventType.js';
import {circular as circularPolygon} from './geom/Polygon.js';
import {GEOLOCATION} from './has.js';
import {toRadians} from './math.js';
import {get as getProjection, getTransformFromProjections, identityTransform} from './proj.js';
/**
* @typedef {Object} Options
* @property {boolean} [tracking=false] Start Tracking right after
* instantiation.
* @property {PositionOptions} [trackingOptions] Tracking options.
* See http://www.w3.org/TR/geolocation-API/#position_options_interface.
* @property {module:ol/proj~ProjectionLike} [projection] The projection the position
* is reported in.
*/
/**
* @classdesc
* Helper class for providing HTML5 Geolocation capabilities.
* The [Geolocation API](http://www.w3.org/TR/geolocation-API/)
* is used to locate a user's position.
*
* To get notified of position changes, register a listener for the generic
* `change` event on your instance of {@link module:ol/Geolocation~Geolocation}.
*
* Example:
*
* var geolocation = new Geolocation({
* // take the projection to use from the map's view
* projection: view.getProjection()
* });
* // listen to changes in position
* geolocation.on('change', function(evt) {
* window.console.log(geolocation.getPosition());
* });
*
* @fires error
* @api
*/
class Geolocation extends BaseObject {
/**
* @param {module:ol/Geolocation~Options=} opt_options Options.
*/
constructor(opt_options) {
super();
const options = opt_options || {};
/**
* The unprojected (EPSG:4326) device position.
* @private
* @type {module:ol/coordinate~Coordinate}
*/
this.position_ = null;
/**
* @private
* @type {module:ol/proj~TransformFunction}
*/
this.transform_ = identityTransform;
/**
* @private
* @type {number|undefined}
*/
this.watchId_ = undefined;
listen(
this, getChangeEventType(GeolocationProperty.PROJECTION),
this.handleProjectionChanged_, this);
listen(
this, getChangeEventType(GeolocationProperty.TRACKING),
this.handleTrackingChanged_, this);
if (options.projection !== undefined) {
this.setProjection(options.projection);
}
if (options.trackingOptions !== undefined) {
this.setTrackingOptions(options.trackingOptions);
}
this.setTracking(options.tracking !== undefined ? options.tracking : false);
}
/**
* @inheritDoc
*/
disposeInternal() {
this.setTracking(false);
super.disposeInternal();
}
/**
* @private
*/
handleProjectionChanged_() {
const projection = this.getProjection();
if (projection) {
this.transform_ = getTransformFromProjections(
getProjection('EPSG:4326'), projection);
if (this.position_) {
this.set(GeolocationProperty.POSITION, this.transform_(this.position_));
}
}
}
/**
* @private
*/
handleTrackingChanged_() {
if (GEOLOCATION) {
const tracking = this.getTracking();
if (tracking && this.watchId_ === undefined) {
this.watchId_ = navigator.geolocation.watchPosition(
this.positionChange_.bind(this),
this.positionError_.bind(this),
this.getTrackingOptions());
} else if (!tracking && this.watchId_ !== undefined) {
navigator.geolocation.clearWatch(this.watchId_);
this.watchId_ = undefined;
}
}
}
/**
* @private
* @param {Position} position position event.
*/
positionChange_(position) {
const coords = position.coords;
this.set(GeolocationProperty.ACCURACY, coords.accuracy);
this.set(GeolocationProperty.ALTITUDE,
coords.altitude === null ? undefined : coords.altitude);
this.set(GeolocationProperty.ALTITUDE_ACCURACY,
coords.altitudeAccuracy === null ?
undefined : coords.altitudeAccuracy);
this.set(GeolocationProperty.HEADING, coords.heading === null ?
undefined : toRadians(coords.heading));
if (!this.position_) {
this.position_ = [coords.longitude, coords.latitude];
} else {
this.position_[0] = coords.longitude;
this.position_[1] = coords.latitude;
}
const projectedPosition = this.transform_(this.position_);
this.set(GeolocationProperty.POSITION, projectedPosition);
this.set(GeolocationProperty.SPEED,
coords.speed === null ? undefined : coords.speed);
const geometry = circularPolygon(this.position_, coords.accuracy);
geometry.applyTransform(this.transform_);
this.set(GeolocationProperty.ACCURACY_GEOMETRY, geometry);
this.changed();
}
/**
* Triggered when the Geolocation returns an error.
* @event error
* @api
*/
/**
* @private
* @param {PositionError} error error object.
*/
positionError_(error) {
error.type = EventType.ERROR;
this.setTracking(false);
this.dispatchEvent(/** @type {{type: string, target: undefined}} */ (error));
}
/**
* Get the accuracy of the position in meters.
* @return {number|undefined} The accuracy of the position measurement in
* meters.
* @observable
* @api
*/
getAccuracy() {
return /** @type {number|undefined} */ (this.get(GeolocationProperty.ACCURACY));
}
/**
* Get a geometry of the position accuracy.
* @return {?module:ol/geom/Polygon} A geometry of the position accuracy.
* @observable
* @api
*/
getAccuracyGeometry() {
return (
/** @type {?module:ol/geom/Polygon} */ (this.get(GeolocationProperty.ACCURACY_GEOMETRY) || null)
);
}
/**
* Get the altitude associated with the position.
* @return {number|undefined} The altitude of the position in meters above mean
* sea level.
* @observable
* @api
*/
getAltitude() {
return /** @type {number|undefined} */ (this.get(GeolocationProperty.ALTITUDE));
}
/**
* Get the altitude accuracy of the position.
* @return {number|undefined} The accuracy of the altitude measurement in
* meters.
* @observable
* @api
*/
getAltitudeAccuracy() {
return /** @type {number|undefined} */ (this.get(GeolocationProperty.ALTITUDE_ACCURACY));
}
/**
* Get the heading as radians clockwise from North.
* Note: depending on the browser, the heading is only defined if the `enableHighAccuracy`
* is set to `true` in the tracking options.
* @return {number|undefined} The heading of the device in radians from north.
* @observable
* @api
*/
getHeading() {
return /** @type {number|undefined} */ (this.get(GeolocationProperty.HEADING));
}
/**
* Get the position of the device.
* @return {module:ol/coordinate~Coordinate|undefined} The current position of the device reported
* in the current projection.
* @observable
* @api
*/
getPosition() {
return (
/** @type {module:ol/coordinate~Coordinate|undefined} */ (this.get(GeolocationProperty.POSITION))
);
}
/**
* Get the projection associated with the position.
* @return {module:ol/proj/Projection|undefined} The projection the position is
* reported in.
* @observable
* @api
*/
getProjection() {
return (
/** @type {module:ol/proj/Projection|undefined} */ (this.get(GeolocationProperty.PROJECTION))
);
}
/**
* Get the speed in meters per second.
* @return {number|undefined} The instantaneous speed of the device in meters
* per second.
* @observable
* @api
*/
getSpeed() {
return /** @type {number|undefined} */ (this.get(GeolocationProperty.SPEED));
}
/**
* Determine if the device location is being tracked.
* @return {boolean} The device location is being tracked.
* @observable
* @api
*/
getTracking() {
return /** @type {boolean} */ (this.get(GeolocationProperty.TRACKING));
}
/**
* Get the tracking options.
* See http://www.w3.org/TR/geolocation-API/#position-options.
* @return {PositionOptions|undefined} PositionOptions as defined by
* the [HTML5 Geolocation spec
* ](http://www.w3.org/TR/geolocation-API/#position_options_interface).
* @observable
* @api
*/
getTrackingOptions() {
return /** @type {PositionOptions|undefined} */ (this.get(GeolocationProperty.TRACKING_OPTIONS));
}
/**
* Set the projection to use for transforming the coordinates.
* @param {module:ol/proj~ProjectionLike} projection The projection the position is
* reported in.
* @observable
* @api
*/
setProjection(projection) {
this.set(GeolocationProperty.PROJECTION, getProjection(projection));
}
/**
* Enable or disable tracking.
* @param {boolean} tracking Enable tracking.
* @observable
* @api
*/
setTracking(tracking) {
this.set(GeolocationProperty.TRACKING, tracking);
}
/**
* Set the tracking options.
* See http://www.w3.org/TR/geolocation-API/#position-options.
* @param {PositionOptions} options PositionOptions as defined by the
* [HTML5 Geolocation spec
* ](http://www.w3.org/TR/geolocation-API/#position_options_interface).
* @observable
* @api
*/
setTrackingOptions(options) {
this.set(GeolocationProperty.TRACKING_OPTIONS, options);
}
}
export default Geolocation;