使用QMetaObject::invokeMethod将槽函数移动到其他线程执行

class ObjTest:public QObject
{
    Q_OBJECT
public:
    void FunTest(){
        qDebug()<<"FunTest"<thread()->currentThread();
        QMetaObject::invokeMethod(this,"slotTest",Qt::AutoConnection);
    }
public slots:
    void slotTest(){
        qDebug()<<"slotTest"<thread()->currentThread();
        // QMessageBox::about(0,0,0);
    }
signals:
    void sigTest();
};

class Test:public QThread
{
    void run()override
    {
        ObjTest* pOBj = new ObjTest();
        // pOBj->moveToThread(qApp->thread());
        pOBj->FunTest();
    }
};

启动Test线程，FunTest和槽函数都在子线程执行

main Thread: QThread(0x18c10129bb0)
FunTest QThread(0x32267cfdc0)
slotTest QThread(0x32267cfdc0)

如果放开注释代码pOBj->moveToThread(qApp->thread());那么FunTest()在子线程中执行，回调的槽函数在主线程中执行，也可以在槽函数中显示窗口了

main Thread: QThread(0x19d8b619fd0)
FunTest QThread(0x3013aff680)
slotTest QThread(0x19d8b619fd0)

static inline bool invokeMethod(QObject *obj, const char *member,Qt::ConnectionType type,

第四个参数如果是异步调用的member，那么是无法计算返回值的

对于invokeMethod()方法，只需要记得信号发出的就是obj对象，member槽函数，就是调用者

信号：obj

槽函数/member：调用invokeMethod的对象