public function getControl()
    {
        $select = parent::getControl();
        $select->name .= '[currency]';
        // $select->id .= '-currency'; // tenhle měnit nechceš, aby na něj šlo prokliknout z labelu
        $select->value = $this->value['currency'];

        $price = parent::getControl();
        $price->name .= '[amount]';
        $price->id .= '-amount';
        $price->value = $this->value['amount'];

        return Html::el()->add($price)->add($select);
    }