roiact/dist/Services/EventDispatcher.js

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;

/**
 * Event Dispatcher
 *
 * Implementation of an event dispatcher following the Mediator pattern
 * @namespace
 */
var EventDispatcher = {
  _prefix: 'on_',
  _listeners: {},

  /**
   * Adds a prefix to the event name
   *
   * Assures that event name doesn't match a standard Object property name
   * @param {String} evtName event name
   * @return {String} prefixed event name
   */
  evtName: function evtName(_evtName2) {
    return this._prefix + _evtName2;
  },

  /**
   * Registers a callback to an event
   *
   * @param {String} evtName name of the event
   * @param {Function} callback function binded to the event
   * @param {Mixed} bind the value of this provided to the callback
   * @return void
   */
  register: function register(evtName, callback, bind) {
    var _evtName = this.evtName(evtName);

    if (typeof this._listeners[_evtName] === 'undefined') {
      this._listeners[_evtName] = [];
    }

    this._listeners[_evtName].push([!bind ? this : bind, callback]);
  },

  /**
   * Unregisters one or all callbacks binded to the given event
   *
   * @param {String} evtName name of the event
   * @param {Function} callback function to unregister. All callbacks if empty
   * @return void
   */
  unregister: function unregister(evtName, callback) {
    var _evtName = this.evtName(evtName);

    if (typeof callback === 'undefined') {
      delete this._listeners[_evtName];
    } else {
      // splice re-indexes the array, so I'm not declaring `var len`
      // but array length is re-computed at every loop cycle
      for (var i = 0; i < this._listeners[_evtName].length; i++) {
        var listener = this._listeners[_evtName][i];

        if (listener[1] === callback) {
          this._listeners[_evtName].splice(i, 1);
        }
      }
    }
  },

  /**
   * Emits an event, all registered callbacks are called
   *
   * @param {String} evtName name of the event
   * @param {Mixed} params additional parameters passed to the callback
   */
  emit: function emit(evtName) {
    var _evtName = this.evtName(evtName);

    if (typeof this._listeners[_evtName] !== 'undefined') {
      for (var _len = arguments.length, params = new Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
        params[_key - 1] = arguments[_key];
      }

      for (var i = 0, l = this._listeners[_evtName].length; i < l; i++) {
        var _this$_listeners$_evt;

        (_this$_listeners$_evt = this._listeners[_evtName][i][1]).call.apply(_this$_listeners$_evt, [this._listeners[_evtName][i][0], evtName].concat(params));
      }
    }
  }
};
var _default = EventDispatcher;
exports.default = _default;