Hi, i got a problem that i can’t solve. I would like to display the current username in profile page but i can’t.
Here are my codes.
register.page.html
<ion-item>
<ion-input type="text" placeholder="Nom utilisateur" [(ngModel)]="dataNewUser.username"></ion-input>
</ion-item>
<ion-item>
<ion-input type="email" placeholder="Email" [(ngModel)]="dataNewUser.email"></ion-input>
</ion-item>
<ion-item>
<ion-input type="password" placeholder="Mot de passe" [(ngModel)]="dataNewUser.password"></ion-input>
</ion-item>
<ion-item>
<ion-input type="password" placeholder="Confirmer mot de passe" [(ngModel)]="dataNewUser.cpassword"></ion-input>
</ion-item>
register.page.ts
import { Component, OnInit } from '@angular/core';
import { AngularFireAuth } from '@angular/fire/auth';
import { ToastController, NavController, ModalController, PopoverController } from '@ionic/angular';
import { auth } from 'firebase';
import * as firebase from 'firebase';
import { AngularFirestore } from '@angular/fire/firestore';
import { UserService } from '../user.service'
import { from } from 'rxjs';
import { AngularFireStorage } from "@angular/fire/storage";
import { url } from 'inspector';
import { Router, NavigationExtras } from '@angular/router';
import { DataApiService } from '../services/data-api.service';
@Component({
selector: 'app-creer-compte',
templateUrl: './creer-compte.page.html',
styleUrls: ['./creer-compte.page.scss'],
})
export class CreerComptePage implements OnInit {
dataNewUser={
email:'',
username:'',
password: '',
cpassword: '',
}
constructor(
public afAuth: AngularFireAuth,
public toastController: ToastController,
public firestore: AngularFirestore,
public storage: AngularFireStorage,
public nav: NavController,
private popoverController: PopoverController,
private router: Router,
) { }
ngOnInit() {
}
async signUp(){
const res= (this.dataNewUser.username, this.dataNewUser.email, this.dataNewUser.password, this.dataNewUser.cpassword)
if(this.dataNewUser.password!==this.dataNewUser.cpassword){
this.toast_mdp_differents();
return console.error("Les mots de passe ne sont pas identiques")
}
if(String(this.dataNewUser.password).length<6){
this.mdp_min_6_caracteres();
}
try{
const res = await this.afAuth.createUserWithEmailAndPassword(this.dataNewUser.email,this.dataNewUser.password)
console.log(res)
this.firestore.collection("Utilisateurs").add({
username: this.dataNewUser.username,
email: this.dataNewUser.email ,
});
}catch(error){
console.dir(error)
this.toast_mail_deja_existant();
}
}
profile.page.html
<ion-item >
<ion-label > //USERNAME SLOT </ion-label>
</ion-item>
profile.page.ts
import { Component, OnInit } from '@angular/core';
import { AngularFireAuth } from '@angular/fire/auth';
import { AngularFirestore, AngularFirestoreDocument } from "@angular/fire/firestore";
import { Observable} from 'rxjs';
@Component({
selector: 'app-tab2',
templateUrl: 'tab2.page.html',
styleUrls: ['tab2.page.scss']
})
export class Tab2Page {
userId: string;
mail: string;
username: any;
items: Observable<any[]>;
constructor(
public afAuth: AngularFireAuth,
public firestore: AngularFirestore,
)
{
this.items = this.firestore.collection('Utilisateurs').valueChanges();
this.afAuth.authState.subscribe(auth => {
if (!auth) {
console.log('non connecté');
} else {
console.log('connecté: ' + auth.email + auth.uid);
this.userId = auth.uid;
this.mail = auth.email;
}
});
}
}
I really need help 
thanks.