Ionic 2 network.type = null

Question

I am developing an application in Ionic 2 ts, but when I try to check if it is connected on the internet it returns null. My code

import { Network } from '@ionic-native/network';


@Component({
  selector: 'page-home',
  templateUrl: 'home.html',
  providers: [ProviderAccessApi]
})
export class HomePage {
  user : string;
  pass:string;

  constructor(public navCtrl: NavController, public providerAPI:ProviderAccessApi, private platform: Platform, public alertCtrl : AlertController, public network : Network) {
      console.log('HomePage carragada com sucesso')
      alert(network.type);
  }

How can I fix ?