text: import {NavController, Page} from 'ionic/ionic';
  import {About} from '../about/about';
  import {Map} from '../map/map';
  import {Sessions} from '../sessions/sessions';
  import {Speakers} from '../speakers/speakers';
  
  @Page({
    templateUrl: 'app/tabs/tabs.html'
  })
  export class Tabs {
    constructor(nav: NavController) {
      // set the root pages for each tab
      this.tab1Root = Sessions;
      this.tab2Root = Speakers;
      this.tab3Root = Map;
      this.tab4Root = About;
    }
  }
  