Ionic中的“无法解析所有参数”

Question

我有这个app.module.ts代码：

import { BrowserModule } from '@angular/platform-browser';
import { ErrorHandler, NgModule } from '@angular/core';
import { IonicApp, IonicErrorHandler, IonicModule, ToastController } from 'ionic-angular';
import { IonicStorageModule } from '@ionic/storage';

import { MyApp } from './app.component';
import { HomePage } from '../pages/home/home';
import { ListPage } from '../pages/list/list';
import {EmailComposer} from '@ionic-native/email-composer';

import { StatusBar } from '@ionic-native/status-bar';
import { SplashScreen } from '@ionic-native/splash-screen';
import { AuthService } from '../providers/auth-service/auth-service';
import { RegisterPage } from '../pages/register/register';
import { LoginPage } from '../pages/login/login';
import { MainPage } from '../pages/main/main';
import { Example_1Page } from '../pages/example-1/example-1';
import { File } from '@ionic-native/file';

import { SignaturePadModule } from 'angular2-signaturepad';
import { Diagnostic } from '@ionic-native/diagnostic';
import {Subscription} from 'rxjs'

@NgModule({
  declarations: [
    MyApp,
    ListPage,
    HomePage,
    MainPage,
    LoginPage,
    RegisterPage,
    Example_1Page

  ],
  imports: [
    BrowserModule,
    SignaturePadModule,
    IonicModule.forRoot(MyApp),
    IonicStorageModule.forRoot()
  ],
  bootstrap: [IonicApp],
  entryComponents: [
    MyApp,

  ],
  providers: [
    Subscription,
    SplashScreen,
    {provide: ErrorHandler, useClass: IonicErrorHandler},
    AuthService,


  ]
})
export class AppModule {}

我需要像上面一样将订阅添加为提供者。但是，当我这样做时，会出现以下错误：

  

错误：无法解析订阅的所有参数（？）。

出什么问题了？其他提供者都没有给我这个问题！

EDIT ：为什么说它需要参数。我尝试将“订阅”添加为页面的提供者，但仍然无法正常工作。这是我从未发生过的事情！