public static function bar($groups, $htmlOptions = array())
    {
        ArrayHelper::addValue('class', 'button-bar', $htmlOptions);

        ob_start();
        echo \CHtml::openTag('div', $htmlOptions);
        foreach ($groups as $group) {
            echo $group;
        }
        echo \CHtml::closeTag('div');
        
        return ob_get_clean();
    }