button_box
Github

    public function button_box()
    {
        return _class('html')->button_box('input_name', ['k1' => 'key1', 'k2' => 'key2']);
    }
    public function button_box($name, $values = [], $selected = '', $extra = [])
    {
        if (is_array($name)) {
            $extra = (array) $extra + $name;
            $name = $extra['name'];
        }
        $desc = isset($extra['desc']) ? $extra['desc'] : ucfirst(str_replace('_', '', $name));
        $values = isset($extra['values']) ? $extra['values'] : (array) $values; // Required
        $translate = isset($extra['translate']) ? $extra['translate'] : 0;
        if ($extra['no_translate']) {
            $translate = 0;
        }
        $selected = isset($extra['selected']) ? $extra['selected'] : $selected;
        $extra['id'] = $extra['id'] ?: __FUNCTION__ . '_' . ++$this->_ids[__FUNCTION__];
        if ( ! $values) {
            return false;
        }
        $selected = (string) $selected;

        $items = [];
        $selected_val = '';
        foreach ((array) $values as $key => $cur_value) {
            $_what_compare = (string) ($type == 1 ? $cur_value : $key);
            $is_selected = $_what_compare == $selected;
            $val = $translate ? t($cur_value) : $cur_value;
            $items[] = '<li class="dropdown' . ($is_selected ? ' active' : '') . '"><a data-value="' . $key . '"' . ($is_selected ? ' data-selected="selected"' : '') . '>' . $val . '</a></li>';
            if ($is_selected) {
                $selected_val = $val;
            }
        }
        $class = $extra['class'] ?: 'btn dropdown-toggle';
        $extra['class_add'] && $class .= ' ' . $extra['class_add'];
        $text = $selected_val ?: $desc;

        $body = [];
        $body[] = '<div class="btn-group" id="' . $extra['id'] . '">';
        if ($extra['button_split']) {
            $body[] = '<button class="btn">' . $text . '</button>';
            $body[] = '<button class="' . $class . '" data-toggle="dropdown"><span class="caret"></span></button>';
        } else {
            $body[] = '<button class="' . $class . '" data-toggle="dropdown">' . $text . ' <span class="caret"></span></button>';
        }
        $body[] = '<ul class="dropdown-menu">';
        foreach ($items as $v) {
            $body[] = $v;
        }
        $body[] = '</ul>';
        $body[] = '</div>';
        return implode(PHP_EOL, $body);
    }