MeshCentral/public/novnc/core/util/eventtarget.js

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2020-06-07 04:55:47 +03:00
/*
* noVNC: HTML5 VNC client
* Copyright (C) 2018 The noVNC Authors
* Licensed under MPL 2.0 (see LICENSE.txt)
*
* See README.md for usage and integration instructions.
*/
export default class EventTargetMixin {
constructor() {
this._listeners = new Map();
}
addEventListener(type, callback) {
if (!this._listeners.has(type)) {
this._listeners.set(type, new Set());
}
this._listeners.get(type).add(callback);
}
removeEventListener(type, callback) {
if (this._listeners.has(type)) {
this._listeners.get(type).delete(callback);
}
}
dispatchEvent(event) {
if (!this._listeners.has(event.type)) {
return true;
}
this._listeners.get(event.type)
.forEach(callback => callback.call(this, event));
return !event.defaultPrevented;
}
}