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 issue while running unit tests. To fix I added the MatSlideToggleModule to the imports in my spect.ts file.

Answer 2

I fixed this error by adding the name="fieldName" ngDefaultControl attributes to the element that carries the [(ngModel)] attribute.

Answer 3

I also had the same error , angular 7

 <button (click)="Addcity(city.name)" [(ngModel)]="city.name"  class="dropdown-item fontstyle"
     *ngFor="let city of Cities; let i = index">
      {{city.name}}
 </button>

I just added ngDefaultControl

   <button (click)="Addcity(city.name)" [(ngModel)]="city.name"  ngDefaultControl class="dropdown-item fontstyle"
 *ngFor="let city of Cities; let i = index">
  {{city.name}}

Answer 4

I also received this error while writing a custom form control component in Angular 7. However, none of the answers are applicable to Angular 7.

In my case, the following needed to be add to the @Component decorator:

  providers: [
    {
      provide: NG_VALUE_ACCESSOR,
      useExisting: forwardRef(() => MyCustomComponent),  // replace name as appropriate
      multi: true
    }
  ]

This is a case of "I don't know why it works, but it does." Chalk it up to poor design/implementation on the part of Angular.

Answer 5

Have you tried moving your [(ngModel)] to the div instead of the switch in your HTML? I had the same error appear in my code and it was because I bound the model to a <mat-option> instead of a <mat-select>. Though I am not using form control.

Answer 6

In my case it was a component.member which was not existing e.g.

[formControl]="personId"

Adding it to the class declaration fixed it

this.personId = new FormControl(...)