Angular，@ViewChild在constructor/ngOninit中子组件的值改变时不更新

Question

Below, I don't underestand why the console.log("My status:",status); not showing while the child property had change,,, this is my child component
in the constructor i have this

    @Output() public isLoged :Subject<boolean>  = new Subject();
    constructor(
    private authService :AuthService,
  ) { 
    
    authService.getLoggedStatus.subscribe(status => this.isLoged.next(status) );
    if(this.authService.isLoggedIn()){
      console.log(" -----Logged---- ");
      this.isLoged.next(true);
      this.authService.getLoggedStatus.next(true);
    }

  } 

and my parent component.ts

    logged :boolean ;
  @ViewChild(LoginComponent) login:LoginComponent;
  ngAfterViewInit() {
      this.login.isLoged.subscribe(status => this.getChildProperty(status));
  }

  getChildProperty(status) {
    this.logged = status;
    console.log("My status :",status);
  }

so the result in the console is just => ** -----Logged---- **

but what i want is ** -----Logged----

My status: true **

Nb:the result shows just in case the code (in the childComp in consructor)is in a Onclock button!

Answer 1

Change the output to EventEmitter instead Subject.

@Output() public isLoged = new EventEmitter ();
this.isLoged.emit(true);

And in the parent component template add the output decorator

<child-component (isLoged)="onLoggedIn($event)"></child-component>

and finally create the function in the parent class

onLoggedIn(isloged) {
    this.getChildProperty(isloged);
}

Answer 2

Thank you all for your reply, I solved my problem by adding the

BehaviorSubject

instead of the Subject .