ERROR Error: No value accessor for form control with unspecified name attribute on switch

Question

Here is my component in Angular 4:

@Component( {
    selector: \'input-extra-field\',
    template: `
            


        
                      

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Answer 1

I was facing this error while running Karma Unit Test cases Adding MatSelectModule in the imports fixes the issue

imports: [
        HttpClientTestingModule,
        FormsModule,
        MatTableModule,
        MatSelectModule,
        NoopAnimationsModule
      ],

Answer 2

I had the same problem and the issue was that my child component had an @input named formControl.

So I just needed to change from:

<my-component [formControl]="formControl"><my-component/>

to:

<my-component [control]="control"><my-component/>

ts:

@Input()
control:FormControl;

Answer 3

I had this same error- I accidentally binded [(ngModel)] to my mat-form-field instead of the input element.

Answer 4

This is kind of stupid, but I got this error message by accidentally using [formControl] instead of [formGroup]. See here:

WRONG

@Component({
  selector: 'app-application-purpose',
  template: `
    <div [formControl]="formGroup"> <!-- '[formControl]' IS THE WRONG ATTRIBUTE -->
      <input formControlName="formGroupProperty" />
    </div>
  `
})
export class MyComponent implements OnInit {
  formGroup: FormGroup

  constructor(
    private formBuilder: FormBuilder
  ) { }

  ngOnInit() {
    this.formGroup = this.formBuilder.group({
      formGroupProperty: ''
    })
  }
}

RIGHT

@Component({
  selector: 'app-application-purpose',
  template: `
    <div [formGroup]="formGroup"> <!-- '[formGroup]' IS THE RIGHT ATTRIBUTE -->
      <input formControlName="formGroupProperty" />
    </div>
  `
})
export class MyComponent implements OnInit {
  formGroup: FormGroup

  constructor(
    private formBuilder: FormBuilder
  ) { }

  ngOnInit() {
    this.formGroup = this.formBuilder.group({
      formGroupProperty: ''
    })
  }
}

Answer 5

In my case i used directive, but hadn't imported it in my module.ts file. Import fixed it.

Answer 6

#Background

• NativeScript 6.0

In my case, the error was triggered by changing element tag from to by fault. Inside <TextView an [(ngModel)]="name". was defined.

After removing [(ngModel)]="name" error was gone.