private function getGroup()
{
if ($this->group != null) {
return $this->group;
}
$group = null;
$callback = function (Component &$component) use(&$group) {
$group = $component;
return Component::VISITOR_STOP_TRAVERSAL;
};
$this->visitParents(CheckBoxGroup::getIdentifier(), $callback);
$this->group = $group;
if ($group == null) {
throw new \RuntimeException('A check must be a child of CheckBoxGroup');
}
return $group;
}
