title: angular6 angularfire not initialized
body: <pre><code>import { CommonModule } from '@angular/common';
  import { NgModule } from '@angular/core';
  import { FlexLayoutModule } from '@angular/flex-layout';
  import { AngularFireModule } from 'angularfire2'
  import { AngularFireAuthModule } from 'angularfire2/auth';
  import { AngularFirestoreModule } from 'angularfire2/firestore';
  import { environment } from '../../environments/environment';
  import { MatButtonModule, MatCheckboxModule, MatInputModule } from '@angular/material';
  import { FormsModule, ReactiveFormsModule } from '@angular/forms';
  import { LoginRoutingModule } from './login-routing.module';
  import { LoginComponent } from './login.component';
  
  
  @NgModule({
      imports: [
          CommonModule,
          LoginRoutingModule,
          MatInputModule,
          MatCheckboxModule,
          MatButtonModule,
          FlexLayoutModule,
          FormsModule, 
          ReactiveFormsModule,
          AngularFireModule.initializeApp(environment.firebase),
          AngularFirestoreModule,
          AngularFireAuthModule, 
      ],
      declarations: [LoginComponent]
  })
  
  export class LoginModule {}
  </code></pre>
  
  <p>above is the code which  for my login module it throw a error on the  console no default app is initialised </p>
  
  <blockquote>
    <p>FirebaseError {code: "app/no-app", message: "Firebase: No Firebase App
    '[DEFAULT]' has been cre…- call Firebase App.initializeApp()
    (app/no-app).", name: "[DEFAULT]", stack: "[DEFAULT]: Firebase: No
    Firebase App '[DEFAULT]' h…ontext
    (<a href="http://localhost:4200/vendor.js:56563:25" rel="nofollow noreferrer">http://localhost:4200/vendor.js:56563:25</a>)"}</p>
  </blockquote>
  
  <p>How to solve it?</p>