Can't use QFont type property values when extending QML properties?

Question

here is my code

mytext.cpp

#ifndef MYTEXT_H
#define MYTEXT_H
#include <QObject>
#include <QtQml/qqml.h>
#include <QFont>

class MyText:public QObject
{
    Q_OBJECT
    Q_PROPERTY(QFont font READ font WRITE setFont)
    Q_PROPERTY(QString fontFamily READ fontFamily WRITE setFontFamily)
    Q_PROPERTY(int fontSize READ fontSize WRITE setFontSize)
    QML_ELEMENT
public:
    MyText(QObject* object = nullptr);

    QString fontFamily()const{return family;}
    void setFontFamily(const QString& fy){family = fy;}

    int fontSize()const{return ftSz;}
    void setFontSize(int sz){ftSz = sz;}

    QFont font()const{return ft;}
    void setFont(const QFont& f){ft = f;}

private:
    QFont ft;
    QString family = "default family";
    int ftSz = 12;
};

main.qml

import QtQuick 2.15
import MyText 1.0

MyText{
    fontFamily:"asdasdad"
    fontSize:20
    //how to set the value of 'font' property ??
}

main.cpp

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QQmlComponent>
#include "mytext.h"

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

    QQmlEngine engine;
    QQmlComponent component(&engine, QUrl("qrc:/main.qml"));
    auto *pMytext = qobject_cast<MyText *>(component.create());

    if (pMytext) {
        qWarning() <<"mytext family is = "<< pMytext->fontFamily()
                  <<"fontSize = "<<pMytext->fontSize()
                 <<"font is = "<<pMytext->font();
        return EXIT_SUCCESS;
    }

    qWarning() << component.errors();
    return EXIT_FAILURE;
}

when i runing ,i get output:

mytext family is = "asdasdad" fontSize = 20 font is = QFont(,-1,-1,5,50,0,0,0,0,0)

so,my question is how could i set the value for the property of 'font'? if no way,how qquicktext work for the element of 'Text'? and one more question,if i change the type QFont to QFont*,is there any way to setting in qml file?