wrapper class for BroadcastChannel

frameMessenger.js

class FrameMessenger {
  constructor(name) {
    this._listeners = {};

    this.name = name || 'frame';
    this.bc = new BroadcastChannel(this.name);

    this.bc.addEventListener('message', e => {
      if (e.data && typeof e.data === 'object' && e.data.type) {
        this.emit(e.data.type, e.data.data);
      }
    });
  }

  emit(name, ...args) {
    (this._listeners[name] || []).forEach(func => func.apply(this, args));
    return this;
  }

  on(name, func) {
    if (name in this._listeners) {
      this._listeners[name].push(func);
    } else {
      this._listeners[name] = [func];
    }
    return this;
  }

  off(name) {
    if (name) {
      this._listeners[name] = [];
    } else {
      this._listeners = {};
    }
    return this;
  }

  send(type, data) {
    this.bc.postMessage({
      type: type,
      data: data
    });
  }
}