Using any c++ function as a Qt slot

Question

Is there a way to use any C++ function as a Qt slot, without having its class inheriting from QWidget?

Answer 1

Since Qt 5, functors and lambda expressions can be used as slot (as previously mentioned, here: http://qt-project.org/wiki/New_Signal_Slot_Syntax).

As I could not find example code, I added the following:

This example uses boost::function for a class member ClassName::classMember() without parameters.

    boost::function f= boost::bind(&ClassName::classMember, classInstance);
    connect(QObjectInstance, &QObject::signalName, f);

When the Qt signal and class member have parameters (for instance ClassName::classMember(int)), the boost function should be adapted as follows:

    boost::function f= boost::bind(&ClassName::classMember, classInstance, _1);

More information on boost::bind can be found in the documentation: http://www.boost.org/doc/libs/1_55_0/libs/bind/bind.html