ts-lib-extended/dist/event/handler.js

Additional types and tools for typescript

import { DisposableBase } from '../disposable/base.js';
import { Event } from './index.js';
/**
 * A handler that provides subscribable, public events.
 * The handler is intended for internal (protected, private) use
 *
 * @export
 * @class EventHandler
 * @template TSender
 * @template {EventArgs | void} [TArgs=void]
 * @extends {DisposableBase}
 * @since 1.0.0
 */
export class EventHandler extends DisposableBase {
    constructor() {
        super();
        this._callbacks = {};
        this._event = new Event((...args_) => this.subscribe(...args_), (...args_) => this.unsubscribe(...args_), (detachEvent_) => {
            this._detachEvent = detachEvent_;
        });
    }
    /**
     * the subscribable event itself
     *
     * @readonly
     * @type {Event<TSender, TArgs>}
     * @memberof EventHandler
     * @since 1.0.0
     */
    get event() {
        return this.validateDisposed(this._event);
    }
    /**
     * trigger/invoke event
     *
     * @param {TSender} sender_
     * @param {TArgs} eventArgs_
     * @memberof EventHandler
     * @since 1.0.0
     */
    invoke(sender_, eventArgs_) {
        const keys = Object.keys(this._callbacks);
        for (let i = 0; i < keys.length; i++) {
            this._callbacks[keys[i]]?.(sender_, eventArgs_);
        }
    }
    subscribe(identifier_, callback_) {
        if (identifier_ in this._callbacks) {
            return false;
        }
        this._callbacks[identifier_] = callback_;
        return true;
    }
    unsubscribe(identifier_) {
        if (identifier_ in this._callbacks) {
            delete this._callbacks[identifier_];
            return true;
        }
        return false;
    }
    disposingInstance() {
        if (this._detachEvent) {
            this._detachEvent();
            this._detachEvent = undefined;
        }
        this._event = undefined;
        const keys = Object.keys(this._callbacks);
        for (let i = 0; i < keys.length; i++) {
            delete this._callbacks[keys[i]];
        }
    }
    disposedInstance() {
        /** there is nothing to do */
    }
}