Agfdhyk

I need to create a simple Fortran program to be bound with a complex Qt program.

The only problem I meet is the utilization of QTimer (which is mandatory): when I call a function using QTimer from Fortran, I always get this error message:

QObject::startTimer: QTimer can only be used with threads started with QThread.

All the other "complex" stuff (QUdpSocket, utilization of classes...) work properly.

How could I solve this problem? After the error message, I think I should find a trick to use QThread for Fortran but I have no idea how to do. (I also tried to inherate dummy from QThread instead of QObject : does not work either)

Here is a simple example. I give now the output and after, the source code.

output when the C++/Qt program is directly launched

begin

hello

end

hello

hello

... // one "hello" per second

output when the f90 program is launched

begin

QObject::startTimer: QTimer can only be used with threads started with QThread

end

main.cpp

#include <QApplication>

#include <QtGui>

#include "dummyclass.hpp"



int main(int argc, char *argv)

{

    QApplication app(argc, argv);

    DummyClass*ds = new DummyClass();

    Q_UNUSED(ds);

    return app.exec();

}

dummyclass.hpp

#include <QTimer>

#include <QObject>

#include <QApplication>

#include <QTextStream>



class dummyclass : public QObject // public QThread

{

    Q_OBJECT



    public:

        DummyClass();



    private:

        QTimer timer;



    private slots:

        void hello();

}

dummyclass.cpp

#include "dummyclass.hpp"



DummyClass::DummyClass()

{

     QTextStream(stdout) << "begin" << endl;

     connect(&timer, SIGNAL(timeout()), this, SLOT(hello()));

     timer.start(1000);

     QTextStream(stdout) << "endl" << endl;

}



void DummyClass::hello()

{

    QTextStream(stdout) << "Hello !" << endl;

}

dummymain.f90

program dummy_main



use dummy_module

    use, intrinsic :: ISO_C_Binding, only: C_CHAR, C_NULL_CHAR

type(dummy_type) :: dummy



call newDummy(dummy)

end program dummy_main

dummy_module.f90

module dummy_module



    use, intrinsic :: ISO_C_Binding, only: C_CHAR, C_NULL_CHAR

    use, intrinsic :: ISO_C_Binding, only: C_ptr, C_NULL_ptr



    implicit none



    private

        type dummy_type

            private

            type(C_ptr) :: object = C_NULL_ptr

        end type dummy_type

    !------------------------

    ! C function declarations

    !------------------------



    interface



        function C_dummyClass__new_ () result(this) bind(C,name="dummyClass__new_")

            import

            type(C_ptr) :: this

        end function C_dummyClass__new_



        subroutine C_dummyClass__delete_ (this) bind(C,name="dummyClass__delete_")

            import

            type(C_ptr), value :: this

        end subroutine C_dummyClass__delete_



    end interface



    interface newDummy

        module procedure newDummy__new

    end interface newDummy



    interface deleteDummy

        module procedure dummyClass__delete

    end interface deleteDummy



    public :: newDummy, deleteDummy



    !------------------------------------------------------------------------------

    CONTAINS

    !------------------------------------------------------------------------------



    !-------------------------------------------------

    ! Fortran wrapper routines to interface C wrappers

    !-------------------------------------------------



    subroutine dummyClass__new(this)

        type(dummy_type), intent(out) :: this

        this%object = C_dummyClass__new_()

    end subroutine dummyClass__new



    subroutine dummyClass__delete(this)

        type(dummy_type), intent(inout) :: this

        call C_dummyClass__delete_(this%object)

        this%object = C_NULL_ptr

    end subroutine dummyClass__delete



    !------------------------------------------------------------------------------



end module dummy_module

compilation

g++ -fPIC -Wall -Wextra -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -DQT_SHARED -lQtGui -lQtCore -lQtNetwork -lpthread -I/usr/include/QtGui -I/usr/include/Qt -I/usr/include/QtCore -I/usr/include/QtNetwork -c *.cpp



gfortran -c *.f90



gfortran -Wall -Wextra -DQT_NO_DEBUG -DQT_GUI_LIB -DQT_CORE_LIB -DQT_SHARED -lQtGui -lQtCore -lQtNetwork -lpthread -I/usr/include/QtGui -I/usr/include/Qt -I/usr/include/QtCore -I/usr/include/QtNetwork -o dummy *.o /home/me/build/dummy/src/moc_dummy_class_.cxx -lstdc++

(note: the moc file for dummy class was already generator by QtCreator)