app.component.ts

import { Component, ViewChild } from '@angular/core';
import { Platform, NavController } from 'ionic-angular';
import { StatusBar } from '@ionic-native/status-bar';
import { SplashScreen } from '@ionic-native/splash-screen';

import { Storage } from '@ionic/Storage';
import { HomePage } from '../pages/home/home';
import { LoginPage } from '../pages/login/login';
import { RegisterPage } from '../pages/register/register';

@Component({
  templateUrl: 'app.html'
})
export class MyApp {
  _platform: Platform;
  public get platform(): Platform {
    return this._platform;
  }
  public set platform(value: Platform) {
    this._platform = value;
  }
  @ViewChild('content') nav: NavController;
  rootPage: any;
  initialization: any;
  initializationApp: any;
  Platform: any;
  statusBar: any;
  splashScreen: any;
  Storage: any;

  constructor(
    public platform: Platform,
    public StatusBar: StatusBar,
    public SplashScreen: SplashScreen,
    private storage: Storage) {
    this.initializationApp();
  }
  initializeApp() {
    this.platform.ready().then(() => {
      this.statusBar.styleDefault();
      this.splashScreen.hide();

    });

    this.storage.get('session_storage').then((res) => {
      if (res == null) {
        this.rootPage = LoginPage;
      } else {
        this.rootPage = HomePage;
      }
    });

  }
}


versão ionic 3.9.5
angular: 5.2.11
node: 10.15.3