code: public function buildView(FormView $view, FormInterface $form, array $options)
      {
          $view->vars['multiple'] = $options['multiple'];
          $view->vars['allowed_filetypes'] = $options['allowed_filetypes'];
          $view->vars['value_media_json'] = $this->getJsonFormatedMedias($view->vars['value']);
          // TODO: implement MediaType Configuration
      }
docs: {@inheritdoc}