添加构造函数参数时 Ionic 4 黑屏

Ionic 4 blank screen when adding constructor parameter

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

这个有效:

constructor(
) { }

但这不起作用:

constructor(
    private formBuilder: FormBuilder 
) { }

我在执行 ionic serve

时出现空白屏幕

尝试将此处提到的 ReactiveForms 添加到您的应用程序模块:

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 { }