在qml中使用c++enum

我有一个 enum 我在qml中使用的

class SettingManager : public QObject
{
    Q_OBJECT
public:
    enum BookKinds{
         BookKind1=0,
         BookKind2=1,
     };
     Q_ENUMS(BookKinds)
     Q_PROPERTY(BookKinds bookKind READ bookKind WRITE setBookKind NOTIFY bookKindChanged)

     explicit SettingManager(QObject *parent = nullptr);
     void setBookKind(BookKinds dkob);
     BookKinds bookKind();
  signals:
    void bookKindChanged();
};

在里面 main.cpp 我注册了 SettingManager

qmlRegisterType<SettingManager>("Test",1,0,"SettingManager");

我在qml文件中使用它

  onCurrentIndexChanged:
    {
        if(tbarBookKindForDisplay.currentIndex==0)
        {
           settingManager.bookKind=BookManager.BookKind1;
        }
        else if(tbarBookKindForDisplay.currentIndex==1){
            settingManager.bookKind=BookManager.BookKind2;
         }           
    }

什么时候 CurrentIndex 属于 TabBar 发生以下更改错误:

错误:无法将[未定义]分配给int