无法解析Qt的QMetaObject :: invokeMethod：没有此类方法错误

cannot resolve Qt's QMetaObject::invokeMethod: No such method error

我正在尝试开发一个通用函数，该函数确定两个QObject是否相等。为了使之成为可能，被比较的函数必须具有"等于"方法，该方法将比较每个函数中的各个函数值，如果它们均相等，则返回true。此外，必须使用Q_INVOKABLE声明此"等于"方法。

但是，当我尝试为'equals'方法调用invokeMethod时，它失败，并显示错误" QMetaObject :: invokeMethod：没有这样的方法F1 :: equals(QObject *)(QObject *)"。 >

这是我的测试项目和文件：

项目文件：

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CONFIG += c++11 console
CONFIG -= app_bundle

# The following define makes your compiler emit warnings if you use
# any feature of Qt which as been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \\
main.cpp

HEADERS += \\
f1.h \\
assert1.h

assert1.h

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#ifndef ASSERT1_H
#define ASSERT1_H

#include <QObject>
#include <QDebug>

class Assert1 : public QObject
{
Q_OBJECT
public:
explicit Assert1(QObject *parent = nullptr) {}
static bool isEqual(QString msg, QObject* o1, QObject* o2)
{
if(o1 != nullptr && o2 != nullptr)
{
if(o1->metaObject()->className() != o2->metaObject()->className())
{
qDebug() << msg <<" not same class type!";
return false;
}
const QMetaObject* metaObject =o1->metaObject();
int ix = metaObject->indexOfMethod(QMetaObject::normalizedSignature("equals(QObject *)"));
qDebug() << QMetaObject::normalizedSignature("equals(QObject *)");
if(ix == -1)
{
qDebug() << msg << tr("indexOfMethod("equals") returns %1").arg(ix);
return false;
}
else
{
bool rslt = false;
if(!QMetaObject::invokeMethod(o1, QMetaObject::normalizedSignature("equals(QObject *)"),
Qt::DirectConnection,
Q_RETURN_ARG(bool, rslt),
Q_ARG(QObject*, o2)))
qDebug() << msg << tr("invoke method 'equals' failed for %1").arg(o1->metaObject()->className());
if(!rslt)
qDebug() << msg << tr(" objects not equal");
return false;
}
}
qDebug() << msg <<"not equal";
}

signals:

public slots:
};

#endif // ASSERT1_H

f1.h

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#ifndef F1_H
#define F1_H

#include <QObject>
#include <QDebug>

class F1 : public QObject
{
Q_OBJECT
public:
explicit F1(int p1, QString p2, QObject *parent = nullptr) : QObject(parent)
{
this->p1 = p1;
this->p2 = p2;
}

void setP1(int p) {this->p1 = p;}
void setP2(QString p) {this->p2 = p;}
Q_INVOKABLE bool equals(QObject* other)
{
if(qobject_cast<F1*>(other) != nullptr)
{
if(this->p1 != ((F1*)other)->p1)
return false;
if(this->p2 != ((F1*)other)->p2)
return false;
}
return true;
}
Q_INVOKABLE QString toString()
{
qDebug() <<"p1 '" << p1 <<" p2 = '" << p2 <<"'";
}

signals:

public slots:
private:
int p1;
QString p2;
};

#endif // F1_H

main.cpp

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#include <QCoreApplication>
#include"f1.h"
#include"assert1.h"
#include <QDebug>

int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);

F1* tf1 = new F1(1,"1");
F1* tf2 = new F1(1,"a");
F1* tf3 = new F1(1,"a");
F1* tf4 = new F1(4,"abc");

qDebug() <<"tf1->equals(tf4) returns:" << (tf1->equals(tf4)?"true":"false");
qDebug() <<"tf2->equals(tf3) returns:" << (tf2->equals(tf3)?"true":"false");
Assert1::isEqual("should be equal", (QObject*)tf2, (QObject*)tf3);

//return a.exec();
}

运行测试会产生以下输出：

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Debugging starts
tf1->equals(tf4) returns: false
tf2->equals(tf3) returns: false
"equals(QObject*)"
QMetaObject::invokeMethod: No such method F1::equals(QObject*)(QObject*)
"should be equal""invoke method 'equals' failed for F1"

如何使invokeMethod起作用？