ionic 2 如何继承一个已经依赖注入 service 的基类？

[gulullu]

基类：

import { LoginPage } from './../login/login/login';
import { AccountData } from './../../storages/account_data';
import { Component, Injectable } from '@angular/core';
import { NavController, NavParams, Platform, ViewController } from 'ionic-angular';
/*
  Generated class for the Base page.

  See http://ionicframework.com/docs/v2/components/#navigation for more info on
  Ionic pages and navigation.
*/

@Component({
  selector: 'page-base',
  templateUrl: 'base.html'
})
export abstract class BasePage {
  needLogin = false;

  constructor(protected accountData: AccountData, protected nav: NavController) { }

  push(page: any) {
    this.accountData.hasLoggedIn().subscribe(hasLoggedIn => {
      if (hasLoggedIn) {
        this.nav.push(page);
      } else {
        if (page.needLogin) {
          this.nav.push(LoginPage);
        } else {
          this.nav.push(page)
        }
      }
    });
  }

  pop() {
    this.nav.pop();
  }

  setRoot(page: any) {
    this.nav.setRoot(page);
  }
}

继承该基类的：

import { AccountData } from './../../storages/account_data';
import { BasePage } from './../base/base';
import { Component } from '@angular/core';
import { NavController, NavParams } from 'ionic-angular';

/*
  Generated class for the Discover page.

  See http://ionicframework.com/docs/v2/components/#navigation for more info on
  Ionic pages and navigation.
*/
@Component({
  selector: 'page-discover',
  templateUrl: 'discover.html'
})
export class DiscoverPage extends BasePage {

  constructor(protected accountData: AccountData, protected navCtrl: NavController, ) {
    super(accountData, navCtrl);
  }

}

运行ionic serve后报错： Uncaught TypeError: Object prototype may only be an Object or null: undefined at setPrototypeOf ()

但是如果父类的构造方法为空的话一切正常，求解。

[bgies]

Change your constuctor to public or private... what happens?

constructor(public accountData: AccountData, public navCtrl: NavController, ) {
super(accountData, navCtrl);
}