IONIC 3 : "Error: No component factory found .... entryComponents?"

Question

Why do I get this error?

Error: No component factory found for DatabaseProvider. Did you add it to @NgModule.entryComponents?

I tried to add my provider to the entryComponents, but still not working.

database.ts

import { HttpClient } from '@angular/common/http';
import { Injectable } from '@angular/core';

import { Storage } from '@ionic/storage';

@Injectable()
export class DatabaseProvider {
  localData: any;
  constructor() {
    console.log('Database provider iniciado ..'); 
  }
}

My settings , With this provider i'm trying to make a local storage, but I can't use this provider.

app.module.ts

import { NgModule, ErrorHandler } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { IonicApp, IonicModule, IonicErrorHandler } from 'ionic-angular';
import { MyApp } from './app.component';
import { StatusBar } from '@ionic-native/status-bar';
import { SplashScreen } from '@ionic-native/splash-screen';
import { DatabaseProvider } from '../providers/database/database';
import { IonicStorageModule } from '@ionic/storage';

@NgModule({
  declarations: [
    MyApp,
    InicioPage,
    SimuladorPage,
    NosotrosPage,
    CuestionarioPage,
    CuestinarioPorCompetenciaPage,
    PersonalizadoPage,
    CRUDPage,
    NormasPage,
    CategoriasPage,
    VerCategoriasPage,
    PreguntasPage,
    AlternativasPage,
    FeedbackPage
  ],
  imports: [
    BrowserModule,
    IonicModule.forRoot(DatabaseProvider),
    IonicStorageModule.forRoot()
  ],
  bootstrap: [IonicApp],
  entryComponents: [
    MyApp,
    InicioPage,
    SimuladorPage,
    NosotrosPage,
    CuestionarioPage,
    CuestinarioPorCompetenciaPage,
    PersonalizadoPage,
    CRUDPage,
    NormasPage,
    CategoriasPage,
    VerCategoriasPage,
    PreguntasPage,
    AlternativasPage,
    FeedbackPage
  ],
  providers: [
    StatusBar,
    SplashScreen,
    {provide: ErrorHandler, useClass: IonicErrorHandler},
    DatabaseProvider
  ]
})
export class AppModule {}

Answer 1

I just had to make a new project ....