How can I validate each FormGroup in a FormArray? Here I have the custom validator:

```
export class GridProcessorValidator {

  static validateGroupItem(definition: ObjectDefinition) {
      return function(control: AbstractControl): ValidatorFn {
          return null;
      };
  }

}

```

And here is the form:

```
this.gridProcessorForm = this.fb.group({
    propertiesSide: new FormControl(),
    objectNamesSide: new FormControl(),
    groupItems: this.fb.array([], validateGroupItem(this.myCollection))   // array of form groups that needs custom validation
});

```

How can I access the values of FormGroups within the custom validator `definitionPropertiesMatched` so I can check it then print it to the template for individual FormGroups that are invalid?

**Template:**

```
*ngFor="let item of gridProcessorForm.get('groupItems').controls; let i=index"
                    [formGroupName]="i"> ...

```

Then I have form field accessor:

```
{{item.get('propertyName').value}}

```

Is there a way I can get any errors for an item (FormGroup) in the iterator?