protected function reloadTree()
    {
        $input        = $this->getEnvironment()->getInputProvider();
        $serializedId = ($input->hasParameter('id') && $input->getParameter('id')) ? $input->getParameter('id') : null;
        $value        = $input->hasValue('value') ? $input->getValue('value', true) : null;

        $this->generateWidget($this->getWidget($this->getFieldName(), $serializedId, $value));

        throw new ResponseException(new Response(''));
    }