eje.ts

import { Injectable } from '@angular/core';

@Injectable()
export class Notifications {
  permition = false;
  constructor() {
    if (!("Notification" in window)) {
      Notification.requestPermission( (e) => this.__granted(e));
    }
  }
  
  __granted(e){
    this.permission = e === "granted";
  }
  
  Notification (text:string) {
    if(this.permission){
      return {};
    }

    return new Notification(text);
  }

  
}