如何传递给 QDataStream - QList<自定义结构>？

有一个使用 QDataStream 从文件加载数据的函数：

void tgTableModel::Load(QString &path)
{
QFile file(path);
if(file.open(QIODevice::ReadOnly))
{
    m_ptargetList->clear();

    QList<target> list; //target моя структура
    QDataStream in(&file);
    in.setVersion(QDataStream::Qt_5_7);
    in >> list;
    m_ptargetList = &list;
    file.close();
}
}

为了让它工作，我为目标结构定义了函数：

struct target{
  QString name;
  QString description;
  int priority;
  QDate deadline;
  Status::Value ready;
};

QDataStream &operator << (QDataStream &stream, const target &tg)
{
  stream << tg.name;
  stream << tg.description;
  stream << tg.priority;
  stream << tg.deadline;
  stream << tg.ready;
  return stream;
}

QDataStream &operator >> (QDataStream &stream, target  &tg)
{
  stream >> tg.name;
  stream >> tg.description;
  stream >> tg.priority;
  stream >> tg.deadline;
  stream >> tg.ready;
  return stream;
}

还为工作流定义了函数>> tg.ready；和流 << tg.ready;

class Status: public QObject
{
Q_OBJECT

public:
explicit Status(QObject * parent = nullptr): QObject(parent){}
enum /*class*/ Value{in_waiting, deferred, completed, in_process, nVariant};
Q_ENUM(Value)

friend QDataStream &operator << (QDataStream &stream, const Status::Value &val)
{
    stream << (int)val;
    return stream;
}
friend QDataStream &operator >> (QDataStream &stream, Status::Value &val)
{
    stream >> (int)val; // вот тут выбивает 4 ошибки!!!
    return stream;
}
};

但在指示的位置，无论我做什么，它都会出现 4 个相同的错误：“...错误：C2679：二进制'>>'：找不到采用'int'类型的右手操作数的运算符（或者没有可接受的转换）”

请帮我解决它。提前致谢！