eventEmitter.js

export default {
  _events: {},
  dispatch: function (event, data) {
    if (!this._events[event]) return // no one is listening to this event
    for (let i = 0; i < this._events[event].length; i++)
      this._events[event][i](data)
  },
  subscribe: function (event, callback) {
    if (!this._events[event]) this._events[event] = [] // new event
    this._events[event].push(callback)
  },
  unSubscribe: function(event){
    if(this._events && this._events[event]) {
      delete this._events[event]
    }
  }
}