@here/harp-mapview/lib/EventDispatcher.js

Functionality needed to render a map.

"use strict";
/*
 * Copyright (C) 2020-2021 HERE Europe B.V.
 * Licensed under Apache 2.0, see full license in LICENSE
 * SPDX-License-Identifier: Apache-2.0
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.EventDispatcher = void 0;
/**
 * JavaScript events for custom objects. Stores all listeners to allow removing all listeners for
 * housekeeping.
 *
 * Will be replaced by `THREE.EventDispatcher` once https://github.com/mrdoob/three.js/pull/19844
 * is released.
 */
class EventDispatcher {
    constructor() {
        this.m_listeners = new Map();
    }
    /**
     * Destroy this `EventDispatcher` instance.
     *
     * Unregister all event handlers used. This is method should be called when you stop
     * using `EventDispatcher`.
     */
    dispose() {
        this.removeAllEventListeners();
    }
    /**
     * Checks if listener is added to an event type.
     *
     * @param type - The type of event to listen to.
     * @param listener - The function that gets called when the event is fired.
     */
    hasEventListener(type, listener) {
        const listeners = this.m_listeners.get(type);
        if (listeners === undefined) {
            return false;
        }
        return listener !== undefined ? listeners.includes(listener) : true;
    }
    /**
     * Add a new event listener to the event type.
     *
     * @param type - The type of event to listen to.
     * @param listener - The function that gets called when the event is fired.
     */
    addEventListener(type, listener) {
        let listeners = this.m_listeners.get(type);
        if (listeners === undefined) {
            listeners = [];
            this.m_listeners.set(type, listeners);
        }
        if (!listeners.includes(listener)) {
            listeners.push(listener);
        }
    }
    /**
     * Remove the listener from the event type.
     *
     * @param type - The type of event to listen to.
     * @param listener - The function that gets called when the event is fired. If the value is
     * `undefined`, all listeners will be removed.
     */
    removeEventListener(type, listener) {
        const listeners = this.m_listeners.get(type);
        if (listeners === undefined) {
            return;
        }
        if (listener === undefined) {
            this.m_listeners.delete(type);
        }
        else {
            const index = listeners.indexOf(listener);
            if (index !== -1) {
                listeners.splice(index, 1);
                if (listeners.length === 0) {
                    this.m_listeners.delete(type);
                }
            }
        }
    }
    /**
     * Remove all event listeners for housekeeping.
     */
    removeAllEventListeners() {
        const events = Array.from(this.m_listeners.keys());
        for (const event of events) {
            this.removeEventListener(event);
        }
    }
    /**
     * Retrieve the registered event types.
     *
     * @returns Array of event types.
     */
    get eventTypes() {
        return Array.from(this.m_listeners.keys());
    }
    /**
     * Retrieve the registered listeners to the specified event.
     *
     * @param type - The type of event to listen to.
     * @returns Array of event listeners.
     */
    listeners(type) {
        return this.m_listeners.get(type);
    }
    /**
     * Dispatch the event to the registered listeners.
     *
     * @param event - The event to dispatch.
     */
    dispatchEvent(event) {
        const listeners = this.m_listeners.get(event.type);
        if (listeners !== undefined) {
            event.target = this;
            // Make a copy, in case listeners are removed while iterating.
            const array = listeners.slice(0);
            for (let i = 0, l = array.length; i < l; i++) {
                array[i].call(this, event);
            }
        }
    }
}
exports.EventDispatcher = EventDispatcher;
//# sourceMappingURL=EventDispatcher.js.map