I have created dynamic form inputs in angular11. need to validate the form fields which added dynamically by clicking add button. i couldnt found the right solutions. here is my code

in component.ts file

```
this.pollAdd = this.fb.group({
      question: ['',Validators.required],
      queChoices:this.fb.array([this.createChoice()]),
    });

addChoice(){
    this.queChoices=this.pollAdd.get('queChoices') as FormArray;
    this.queChoices.push(this.createChoice());
  }

  createChoice():FormGroup{
    return this.fb.group({
      choice:['',Validators.required],
    })
  }

get f() { return this.pollAdd.controls; }

```

In component.html file

```
<div formArrayName="queChoices" *ngFor="let choices of pollAdd.get('queChoices')['controls'];let i=index;">
        <mat-form-field class="ch__custom_input w-100 mt-3" [formGroupName]="i">
          <mat-label>Choice {{i+1}}</mat-label>
          <input matInput formControlName="choice" autofocus/>
        </mat-form-field>
      </div>

```

how to validate each choice field?