public function setItems(array $items, $useKeys = TRUE)
{
if (!$useKeys) {
$res = [];
foreach ($items as $key => $value) {
unset($items[$key]);
if (is_array($value)) {
foreach ($value as $val) {
$res[$key][(string) $val] = $val;
}
} else {
$res[(string) $value] = $value;
}
}
$items = $res;
}
$this->options = $items;
return parent::setItems(Nette\Utils\Arrays::flatten($items, TRUE));
}