Cannot find control with name:

Question

I have a quite complicated form which I want to break down into individual components. Here is my base form (only taken example fields), I'm using FormBuilder:

ngOnInit() {
  this.predictorQuestion = this.fb.group({
  question: ['', Validators.required],
  options: this.fb.array([
    this.fb.control('', Validators.required),
  ]),
  meta_options: this.fb.group({
   test_type: ['', Validators.required],
  })
});

get meta_options() {
  return this.predictorQuestion.get('meta_options') as FormGroup;
}

get options() {
  return this.predictorQuestion.get('options') as FormArray;
}

If I try to connect this to my templates, it works perfectly:

<form [formGroup]="predictorQuestion" fxLayout="column">
  <mat-form-field fxFlex appearance="outline">
    <mat-label>Question</mat-label>
    <input matInput formControlName="question">
  </mat-form-field>

  <div fxLayoutAlign="space-between center">
    <h3>Options</h3>
    <button (click)="addOption()" matTooltip="Add option" matTooltipPosition="right" mat-mini-fab type="button">
      <mat-icon>add</mat-icon>
    </button>
  </div>
  <div formArrayName="options" fxLayout="column">
    <div *ngFor="let answer of options.controls; let i = index" fxLayout="row" fxLayoutAlign="space-between stretch">
      <mat-form-field appearance="outline" fxFlex>
        <mat-label>Option {{ i+1 }} </mat-label>
        <input fxFlex matInput [formControlName]="i">
      </mat-form-field>
      <button mat-icon-button matTooltip="Remove this option" matTooltipPosition="right" (click)="removeOption(i)">
        <mat-icon>close</mat-icon>
      </button>
    </div>
  </div>

  <div formGroupName="meta_options" fxLayoutAlign="space-between" fxLayoutGap="20px" fxLayout="column">
    <mat-form-field fxFlex="25">
      <mat-select formControlName="test_type">
        <mat-option *ngFor="let vtype of vtypes" value="{{ vtype.value }}">{{ vtype.name }}</mat-option>
      </mat-select>
    </mat-form-field>
  </div>
</form>

This renders without any errors.

If I try to break down the meta_options.test_type in a component of its own in a way like:

component.ts

@Input() parent_form: FormGroup;
public vtypes: Array<Object>;


  constructor(private fb: FormBuilder) {
    this.vtypes = [
      {
        name: 'Timestamp',
        value: 'timestamp'
      },
      {
        name: 'Over',
        value: 'over'
      }
    ];
  }

component.html

<mat-form-field fxFlex="25" [formGroup]="parent_form">
  <mat-select formControlName="test_type">
    <mat-option *ngFor="let vtype of vtypes" value="{{ vtype.value }}">{{ vtype.name }}</mat-option>
  </mat-select>
</mat-form-field>

and using this component in my main parent form as

<meta-option-value [parent_form]="predictorQuestion"></meta-option-value>

I get the following error:

"Cannot find the control with the name: 'test_type'"

What am I missing here?

Answer 1

You are passing the complete FormGroup (predictorQuestion) to the child. You only need to pass the predictorQuestion.get('meta_types') to the parent_form as [parent_form]="predictorQuestion.get('meta_types')".