profile page ts file

import { Component, NgZone } from '@angular/core';
import { NavController, NavParams, App } from 'ionic-angular';

import { AngularFireAuth } from 'angularfire2/auth';
import * as firebase from 'firebase';

import { PurchasePage } from '../purchase/purchase';
import { WelcomePage } from '../welcome/welcome';
import { EditprofilePage } from '../editprofile/editprofile';
import { User } from '../../models/user';
import { UsercrudProvider } from '../../providers/usercrud/usercrud';

@Component({
  selector: 'page-me',
  templateUrl: 'me.html',
})
export class MePage {
  user = {} as User;
  avatar: any;

  constructor(public navCtrl: NavController, public navParams: NavParams,
    public afAuth: AngularFireAuth, private app: App, public userservice: UsercrudProvider,
    public zone: NgZone, ) {

  }

  ionViewWillLoad() {
    this.loaduserdetails();
  }

  loaduserdetails() {
    this.userservice.getUserDetails().then((res: any) => {
      this.zone.run(() => {
        this.avatar = res.photoURL;
      })
    })
  }

  ionViewDidLoad() {
    console.log('ionViewDidLoad EditprofilePage');
    var person = firebase.auth().currentUser;
    var uid = person.uid;

    const profileDetails = firebase.database().ref(`userprofile/${uid}`);
    profileDetails.on('value', snapshot => {
      this.user = snapshot.val();
      console.log('profileDetails',this.user);
    });
    }



  myprofile() {
    this.navCtrl.push(EditprofilePage);
  }

  PurchasePage() {
    this.navCtrl.push(PurchasePage);
  }

  // editprofile(){
  //   this.navCtrl.push(EditprofilePage);
  // }

  onLogout() {
    this.afAuth.auth.signOut()
      .then(() => {
        this.navCtrl.setRoot(WelcomePage);
        // this.nav.rootNav.setRoot(WelcomePage);
        this.app.getRootNav().setRoot(WelcomePage);
        console.log('logout');
      }).catch(function (error) {
        // An error happened.
      });
  }

}