OpenLayers源码解析12 ol/Feature.js

ol/Feature.js

父类

ol/Object-BaseObject

主要功能

矢量要素，有geometry和其他的属性。
可以用setStyle设置样式，或者使用layer的样式。
所有的属性会被设置为基础属性，可以被get/set到。
feature都有一个单独的geometry，可以用setGeometry和getGeometry，或者用geometry参数指定。
如果想要使用另外一个geometry渲染，使用setGeometryName改变默认渲染的geometry名。

参数：Feature({})

参数	类型	说明
geometryOrProperties	Geometry Object.<string, *>	geometry或者其他属性

方法

函数名	参数	源码	返回值类型	功能
getGeometry()	无	Feature.js, line 174	{Geometry	undefined}

/**
 * @module ol/Feature
 */
import BaseObject from './Object.js';
import EventType from './events/EventType.js';
import {
   assert} from './asserts.js';
import {
   listen, unlistenByKey} from './events.js';

/**
 * @typedef {typeof Feature|typeof import("./render/Feature.js").default} FeatureClass
 */

/**
 * @typedef {Feature<import("./geom/Geometry.js").default>|import("./render/Feature.js").default} FeatureLike
 */

/***
 * @template Return
 * @typedef {import("./Observable").OnSignature<import("./Observable").EventTypes, import("./events/Event.js").default, Return> &
 *   import("./Observable").OnSignature<import("./ObjectEventType").Types|'change:geometry', import("./Object").ObjectEvent, Return> &
 *   import("./Observable").CombinedOnSignature<import("./Observable").EventTypes|import("./ObjectEventType").Types
 *     |'change:geometry', Return>} FeatureOnSignature
 */

/***
 * @template Geometry
 * @typedef {Object<string, *> & { geometry?: Geometry }} ObjectWithGeometry
 */

/**
 * @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 module: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
 *
 * import Feature from 'ol/Feature';
 * import Polygon from 'ol/geom/Polygon';
 * import Point from 'ol/geom/Point';
 *
 * var feature = new Feature({
 *   geometry: new Polygon(polyCoords),
 *   labelPoint: new 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();
 * ```
 *
 * @api
 * @template {import("./geom/Geometry.js").default} Geometry
 */
class Feature extends BaseObject {
   
  /**
   * @param {Geometry|ObjectWithGeometry<Geometry>} [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.
   */
  constructor(opt_geometryOrProperties) {
   
    super();

    /***
     * @type {FeatureOnSignature<import("./Observable.js").OnReturn>}
     */
    this.on;

    /***
     * @type {FeatureOnSignature<import("./Observable.js").OnReturn>}
     */
    this.once