/**
  * @param ITrackQuestionTemplate $question
  * @param ITrackAnswer $answer
  * @return FormField
  */
 public function build(ITrackQuestionTemplate $question, ITrackAnswer $answer)
 {
     $field = new CheckboxField($question->name(), $question->label());
     $field->setFieldHolderTemplate('BootstrapFieldHolder');
     $field->setValue($question->initialValue());
     if ($question->isReadOnly()) {
         $field->setDisabled(true);
     }
     if ($question->isMandatory()) {
         $field->setAttribute('data-rule-required', 'true');
     }
     if (!is_null($answer)) {
         $field->setValue($answer->value());
     }
     $field->setFieldHolderTemplate('RSVPCheckboxField_holder');
     return $field;
 }