/**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state) {
    // @todo Remove require fields for drafts. This would require JS too.
    parent::submitForm($form, $form_state);
    $eform_type = $this->entity->getEFormType();
    if ($eform_type->preview_page) {
      $this->setMode($this::MODE_PREVIEW);

    }
  }
 /**
  * Determine Form Display for that should be used for a submission
  *
  * @param \Drupal\eform\Entity\EFormSubmission $eform_submission
  *
  * @return string
  *  Id for Form Display Mode
  */
 function getFormMode(EFormSubmission $eform_submission) {
   if ($eform_submission->isDraft()) {
     return 'submit_draft';
   }
   if ($eform_submission->isNew()) {
     return 'submit';
   }
   else {
     return 'submit_previous';
   }
 }