Question

我的环境：Qt5.5 + QtCreator3.5 + OSX10.11

我知道qt5和qt4中函数connect的语法不同，查找Document以了解如何在qt5中使用connect（）来处理重载信号/槽函数。

我按照建议做，但它仍然无法正常工作。

newspaper.h

signals:
    // overload function
    void newPaper(const QString &name) const;
    void newPaper(const QString &name, const QDate &date) const;

reader.h

//overload function
void receiveNewspaper(const QString &name) const
{
    qDebug() << "overload(name): Receives Newspaper: " << name;
}
//overload function
void receiveNewspaper(const QString &name, const QDate &date) const
{
    qDebug() << "overload(name, date): Receives Newspaper: " << name << "\tDate:" << date;
}

的main.cpp

//connect for overload signal,slot function
QObject::connect(&newspaper,
                 static_cast<void (Newspaper:: *)(const QString &)>(&Newspaper::newPaper),
                 &reader,
                 static_cast<void (Reader:: *)(const QString &)>(&Reader::receiveNewspaper) );

但它得到如下错误

./2_16_SignalSlotDeep/main.cpp:16:22: error: address of overloaded function 'newPaper' cannot be static_cast to type 'void (Newspaper::*)(const QString &)'
                     static_cast<void (Newspaper::*)(const QString &)>(&Newspaper::newPaper),
                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../2_16_SignalSlotDeep/newspaper.h:28:10: note: candidate function
    void newPaper(const QString &name) const;
         ^
../2_16_SignalSlotDeep/newspaper.h:29:10: note: candidate function
    void newPaper(const QString &name, const QDate &date) const;
         ^
../2_16_SignalSlotDeep/main.cpp:18:22: error: address of overloaded function 'receiveNewspaper' cannot be static_cast to type 'void (Reader::*)(const QString &)'
                     static_cast<void (Reader::*)(const QString &)>(&Reader::receiveNewspaper) );
                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../2_16_SignalSlotDeep/reader.h:16:10: note: candidate function
    void receiveNewspaper(const QString &name) const
         ^
../2_16_SignalSlotDeep/reader.h:21:10: note: candidate function
    void receiveNewspaper(const QString &name, const QDate &date) const

我已经搜索了对我没用的其他问题。怎么解决？您的建议将不胜感激。

qt5：使用static_cast连接过载信号和插槽功能

1 个答案: