5.) User authentification example code broken

[daslicht]

Hi,
the 5-user-authentication.md consists of the following example code:

Login users

export class AppComponent {
  constructor(public af: AngularFire) {}

 login() {
    this.af.auth.login();
  }

  logout() {
     this.af.auth.logout();
  }
}

We get the following error:

[ts] Property 'af' does not exist on type 'AppComponent'.

Looks like af is not being added automatically to the this scope automatically.

Should it be :

export class AppComponent {
  af: AngularFire;
  title = 'app works!';

  item: FirebaseObjectObservable<any>;

  constructor(af: AngularFire) {
    this.af =  af ;
    this.item = af.database.object('/item');
  }

  login() {
      this.af.auth.login();
    }

  logout() {
     this.af.auth.logout();
  }
}

But there must be a better way to initialize af since the Angualr 2 docs say that it is not good practice to do such things in the constructor and rather use:

  ngOnInit() {
  }

But how to inject public af: AngularFire to ngOnInit()
please?

[gianpaj]

I believe instantiating the AngularFire class in the constructor makes sense instead of ngOnInit().

See http://stackoverflow.com/a/35763811/728287

So You should use constructor() to setup Dependency Injection and not much else. ngOnInit() is better place to "start" - it's where/when components' bindings are resolved

[ykoehler]

What if you add the @component decorator, does it work in the constructor?

[daslicht]

What if you add the @component decorator, does it work in the constructor?
? it already woks in the constructor like this:

  constructor(af: AngularFire) {
    this.af =  af ;
    this.item = af.database.object('/item');
  }

I asked fro using it in ngOnInit() since it was proposed here:
#637

[daslicht]

Ok I found the issue , the af variable in the constructor needas to be private or public

constructor( private af: AngularFire) {