button_check_box
Github

	function button_check_box() {
		return _class('html')->button_check_box('input_name', ['k1' => 'key1', 'k2' => 'key2']);
	}
	function button_check_box($name, $values = [], $selected = '') {
		if (is_array($name)) {
			$extra = (array)$extra + $name;
			$name = $extra['name'];
		}
		!is_array($extra) && $extra = [];
		$label_extra = $extra['label_extra'];
		$extra = [
			'name' => $name,
			'values' => $values,
			'selected' => $selected,
			'use_stpl' => false,
			'label_extra' => [
				'class' => ($label_extra['class'] ?: $this->CLASS_LABEL_BTN_CHECKBOX),
			],
		] + $extra;
		return '<div class="btn-group" data-toggle="buttons">'.$this->check_box($extra).'</div>';
	}