Changing the caret (cursor) color in NativeScript iOS

nativescript-ios-caret-color.ts

export class MyComponent implements AfterViewInit {
  // assuming your view has this: <TextField #myTextField text="I have a red caret"></TextField>
  @ViewChild("myTextField") myTextField: ElementRef;

  ngAfterViewInit(): void {
    // note that if you don't have iOS typings you can change 'UITextField' to 'any'
    let textField: UITextField = (<TextField>this.myTextField.nativeElement).ios;
    textField.tintColor = new Color("red").ios;
  }
}

(this.myTextField.nativeElement).ios is always undefined.