EventsMixin

events_mixin.js

(function(App, Array) {
  'use strict';
  var slice = Array.prototype.slice;

  function Events () {
    var events = {};

    function on (eventName, callback, context) {
      if (!events[eventName]) {
        events[eventName] = [];
      }

      events[eventName].push({ callback: callback, context: context });
    }

    function off (eventName) {
      if (events[eventName]) {
        // faster that .splice
        events[eventName] = [];
      }
    }

    function trigger (eventName) {
      var args = slice.call(arguments, 1);
      var registeredArr = events[eventName];
      var len;
      var registered;

      if (registeredArr) {
        len = registeredArr.length;

        for(var i = 0; i < len; i++) {
          registered = registeredArr[i];
          registered.callback.apply(registered.context, args);
        }
      }
    }

    return function () {
      this.on = on;
      this.off = off;
      this.trigger = trigger;

      return this;
    };
  }

  App.mixins.Events = Events;
})(App, Array);