求大神指教checkboxList用法 [ 2.0 版本 ]

视图

<?= $form->field($model, 'type')->checkboxList(\common\models\Product::getType()) ?>

添加时报错

模型

    /**
     * @param null $type
     * @return array|string
     */
    public static function getType($type = null)
    {
        $data = [
            self::IS_NEW => '新品',
            self::IS_HOT => '热销',
            self::IS_GIRT => '赠品',
            self::IS_PROMOTION => '促销',
            self::IS_GROUP => '团购',
        ];
        if ($type === null) {
            return $data;
        } else {
            $str = '';
            foreach ($data as $k => $v) {
                if ($type & $k) {
                    $str .= ' ' . $data[$k];
                }
            }
            return $str;
        }
    }