...
import { AboutUsPage } from '../pages/aboutus/aboutus';
import { TabAdminPage } from '../pages/tabadmin/tabadmin';
import { AdminPage } from '../pages/admin/admin';
import { DeleteInventoryPage } from '../pages/deleteinventory/deleteinventory';
import { HomePage } from '../pages/home/home';
...
@NgModule({
  declarations: [
    MyApp,
    AboutUsPage,
    HomePage,
    AdminPage,
    TabAdminPage,
    DeleteInventoryPage
  ],
 ...
 entryComponents: [
    MyApp,
    AboutUsPage,
    HomePage,
    AdminPage,
    TabAdminPage,
    DeleteInventoryPage
  ],
...
export class AppModule {}