Translation in symfony form event

Question

In a custom formType I have an evenListener

$builder->add('somefield');
....
//surveyor and surveyorid can't be empty
$builder->addEventListener(FormEvents::PRE_SUBMIT, function (FormEvent $event) {
    $data = $event->getData();
    if($data['surveyor']=='' && $data['surveyorid']==''){
    form = $event->getForm();
    $form->addError(new \Symfony\Component\Form\FormError('esto.esta.mal'));
}
});

The first argument of FormError() is "The translated error message", so, if If I don't like to pass the translator as argument to the formType and I can't get the translator in my formType. How can I translate this custom error?

My intermediate solution is to translate all form errors and pass them as options to the form. This is a sort example:

In controller:

....
editAction(Request $request)
{ 

//translate errors 
$errors = [
'form.map.surveyor.incomplete'=>$this->get('translator')->trans('form.map.surveyor.incomplete'),
'form.map.surveyor.chooseonefield'=>$this->get('translator')->trans('form.map.surveyor.chooseonefield'),    
];

//
$form = $this->createForm( $formType, $entity, ['errors'=>$errors]);

....
if ($form->isValid()) {
...
}else{errors to string
return new \Symfony\Component\HttpFoundation\JsonResponse(['e'=>(string) $form->getErrors(true, false)]);
}
....

In formType, something like:

public function buildForm(FormBuilderInterface $builder, array $defaults)
{
    $errors = $defaults['errors'];//translated errors
....

     $builder->addEventListener(FormEvents::PRE_SUBMIT, function (FormEvent $event) use ($errors) {
        $data = $event->getData();
        if($data['surveyor']=='' && $data['surveyorid']==''){
            $form = $event->getForm();
            $form->addError(new \Symfony\Component\Form\FormError( sprintf($errors['form.map.surveyor.incomplete'] )));
        }
        if($data['surveyor']!=='' && $data['surveyorid']!==''){
            $form = $event->getForm();
            $form->addError(new \Symfony\Component\Form\FormError($errors['form.map.surveyor.chooseonefield']));
        }              
     });    
....

/**
 * @param OptionsResolver $resolver
 */
public function configureOptions(OptionsResolver $resolver)
{
    $resolver->setDefaults(array(
        'data_class' => 'Gpt\MyBundle\Entity\Mapsurveyor',
        'errors'=>array()
        ));
         
}

I would rather a more elegant solution

Any help will be appreciated

EDIT

Autowire is available in constructor formTypes

class MyformType extends AbstractType
{
    /**
     * @var TranslatorInterface 
     */
    private $translator;
    
    public function __construct(TranslatorInterface $translator)
    {
        $this->translator= $translator;      
    }