Ionic 4 blank screen when adding constructor parameter

Question

import { FormBuilder} from '@angular/forms';

This works:

constructor(
) { }

But this does not work:

constructor(
    private formBuilder: FormBuilder 
) { }

I get a blank white screen when doing ionic serve

Answer 1

Try adding ReactiveForms as mentioned here to your app module:

https://angular.io/guide/reactive-forms#step-1-registering-the-reactive-forms-module

import { ReactiveFormsModule } from '@angular/forms';

@NgModule({
  imports: [
    // other imports ...
    ReactiveFormsModule
  ],
})
export class AppModule { }