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openlayers

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Build tools and sources for developing OpenLayers based mapping applications

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goog.provide('ol.Feature'); goog.require('ol.asserts'); goog.require('ol.events'); goog.require('ol.events.EventType'); goog.require('ol'); goog.require('ol.Object'); goog.require('ol.geom.Geometry'); goog.require('ol.style.Style'); /** * @classdesc * A vector object for geographic features with a geometry and other * attribute properties, similar to the features in vector file formats like * GeoJSON. * * Features can be styled individually with `setStyle`; otherwise they use the * style of their vector layer. * * Note that attribute properties are set as {@link ol.Object} properties on * the feature object, so they are observable, and have get/set accessors. * * Typically, a feature has a single geometry property. You can set the * geometry using the `setGeometry` method and get it with `getGeometry`. * It is possible to store more than one geometry on a feature using attribute * properties. By default, the geometry used for rendering is identified by * the property name `geometry`. If you want to use another geometry property * for rendering, use the `setGeometryName` method to change the attribute * property associated with the geometry for the feature. For example: * * ```js * var feature = new ol.Feature({ * geometry: new ol.geom.Polygon(polyCoords), * labelPoint: new ol.geom.Point(labelCoords), * name: 'My Polygon' * }); * * // get the polygon geometry * var poly = feature.getGeometry(); * * // Render the feature as a point using the coordinates from labelPoint * feature.setGeometryName('labelPoint'); * * // get the point geometry * var point = feature.getGeometry(); * ``` * * @constructor * @extends {ol.Object} * @param {ol.geom.Geometry|Object.<string, *>=} opt_geometryOrProperties * You may pass a Geometry object directly, or an object literal * containing properties. If you pass an object literal, you may * include a Geometry associated with a `geometry` key. * @api stable */ ol.Feature = function(opt_geometryOrProperties) { ol.Object.call(this); /** * @private * @type {number|string|undefined} */ this.id_ = undefined; /** * @type {string} * @private */ this.geometryName_ = 'geometry'; /** * User provided style. * @private * @type {ol.style.Style|Array.<ol.style.Style>| * ol.FeatureStyleFunction} */ this.style_ = null; /** * @private * @type {ol.FeatureStyleFunction|undefined} */ this.styleFunction_ = undefined; /** * @private * @type {?ol.EventsKey} */ this.geometryChangeKey_ = null; ol.events.listen( this, ol.Object.getChangeEventType(this.geometryName_), this.handleGeometryChanged_, this); if (opt_geometryOrProperties !== undefined) { if (opt_geometryOrProperties instanceof ol.geom.Geometry || !opt_geometryOrProperties) { var geometry = opt_geometryOrProperties; this.setGeometry(geometry); } else { /** @type {Object.<string, *>} */ var properties = opt_geometryOrProperties; this.setProperties(properties); } } }; ol.inherits(ol.Feature, ol.Object); /** * Clone this feature. If the original feature has a geometry it * is also cloned. The feature id is not set in the clone. * @return {ol.Feature} The clone. * @api stable */ ol.Feature.prototype.clone = function() { var clone = new ol.Feature(this.getProperties()); clone.setGeometryName(this.getGeometryName()); var geometry = this.getGeometry(); if (geometry) { clone.setGeometry(geometry.clone()); } var style = this.getStyle(); if (style) { clone.setStyle(style); } return clone; }; /** * Get the feature's default geometry. A feature may have any number of named * geometries. The "default" geometry (the one that is rendered by default) is * set when calling {@link ol.Feature#setGeometry}. * @return {ol.geom.Geometry|undefined} The default geometry for the feature. * @api stable * @observable */ ol.Feature.prototype.getGeometry = function() { return /** @type {ol.geom.Geometry|undefined} */ ( this.get(this.geometryName_)); }; /** * Get the feature identifier. This is a stable identifier for the feature and * is either set when reading data from a remote source or set explicitly by * calling {@link ol.Feature#setId}. * @return {number|string|undefined} Id. * @api stable * @observable */ ol.Feature.prototype.getId = function() { return this.id_; }; /** * Get the name of the feature's default geometry. By default, the default * geometry is named `geometry`. * @return {string} Get the property name associated with the default geometry * for this feature. * @api stable */ ol.Feature.prototype.getGeometryName = function() { return this.geometryName_; }; /** * Get the feature's style. Will return what was provided to the * {@link ol.Feature#setStyle} method. * @return {ol.style.Style|Array.<ol.style.Style>| * ol.FeatureStyleFunction} The feature style. * @api stable * @observable */ ol.Feature.prototype.getStyle = function() { return this.style_; }; /** * Get the feature's style function. * @return {ol.FeatureStyleFunction|undefined} Return a function * representing the current style of this feature. * @api stable */ ol.Feature.prototype.getStyleFunction = function() { return this.styleFunction_; }; /** * @private */ ol.Feature.prototype.handleGeometryChange_ = function() { this.changed(); }; /** * @private */ ol.Feature.prototype.handleGeometryChanged_ = function() { if (this.geometryChangeKey_) { ol.events.unlistenByKey(this.geometryChangeKey_); this.geometryChangeKey_ = null; } var geometry = this.getGeometry(); if (geometry) { this.geometryChangeKey_ = ol.events.listen(geometry, ol.events.EventType.CHANGE, this.handleGeometryChange_, this); } this.changed(); }; /** * Set the default geometry for the feature. This will update the property * with the name returned by {@link ol.Feature#getGeometryName}. * @param {ol.geom.Geometry|undefined} geometry The new geometry. * @api stable * @observable */ ol.Feature.prototype.setGeometry = function(geometry) { this.set(this.geometryName_, geometry); }; /** * Set the style for the feature. This can be a single style object, an array * of styles, or a function that takes a resolution and returns an array of * styles. If it is `null` the feature has no style (a `null` style). * @param {ol.style.Style|Array.<ol.style.Style>| * ol.FeatureStyleFunction} style Style for this feature. * @api stable * @observable */ ol.Feature.prototype.setStyle = function(style) { this.style_ = style; this.styleFunction_ = !style ? undefined : ol.Feature.createStyleFunction(style); this.changed(); }; /** * Set the feature id. The feature id is considered stable and may be used when * requesting features or comparing identifiers returned from a remote source. * The feature id can be used with the {@link ol.source.Vector#getFeatureById} * method. * @param {number|string|undefined} id The feature id. * @api stable * @observable */ ol.Feature.prototype.setId = function(id) { this.id_ = id; this.changed(); }; /** * Set the property name to be used when getting the feature's default geometry. * When calling {@link ol.Feature#getGeometry}, the value of the property with * this name will be returned. * @param {string} name The property name of the default geometry. * @api stable */ ol.Feature.prototype.setGeometryName = function(name) { ol.events.unlisten( this, ol.Object.getChangeEventType(this.geometryName_), this.handleGeometryChanged_, this); this.geometryName_ = name; ol.events.listen( this, ol.Object.getChangeEventType(this.geometryName_), this.handleGeometryChanged_, this); this.handleGeometryChanged_(); }; /** * Convert the provided object into a feature style function. Functions passed * through unchanged. Arrays of ol.style.Style or single style objects wrapped * in a new feature style function. * @param {ol.FeatureStyleFunction|!Array.<ol.style.Style>|!ol.style.Style} obj * A feature style function, a single style, or an array of styles. * @return {ol.FeatureStyleFunction} A style function. */ ol.Feature.createStyleFunction = function(obj) { var styleFunction; if (typeof obj === 'function') { styleFunction = obj; } else { /** * @type {Array.<ol.style.Style>} */ var styles; if (Array.isArray(obj)) { styles = obj; } else { ol.asserts.assert(obj instanceof ol.style.Style, 41); // Expected an `ol.style.Style` or an array of `ol.style.Style` styles = [obj]; } styleFunction = function() { return styles; }; } return styleFunction; };