cannot call member function without object

[been_1990]

I get the following error when trying to connect two classes together:

qapp.cpp: In static member function 'static bool QApp::eventFilter(void*)':
qapp.cpp:32: error: cannot call member function 'void QApp::mouseCoord(int, int, int, int, int)' without object

qapp.cpp: In static member function 'static bool QApp::eventFilter(void*)':
qapp.cpp:32: error: cannot call member function 'void QApp::mouseCoord(int, int, int, int, int)' without object

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main.cpp:

int main(int argc, char *argv[])
{
    QApp a(argc, argv);
    Widget w;
    w.show();
 
    QObject::connect(&a,SIGNAL(mouseCoords(int, int, int, int, int)),
                     &w,SLOT(mouseCoords(int, int, int, int, int)));
 
    return a.exec();
}

int main(int argc, char *argv[])
{
    QApp a(argc, argv);
    Widget w;
    w.show();

    QObject::connect(&a,SIGNAL(mouseCoords(int, int, int, int, int)),
                     &w,SLOT(mouseCoords(int, int, int, int, int)));

    return a.exec();
}

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qapp.cpp:

emit mouseCoord(get_raw_mouse_x_delta(i), get_raw_mouse_y_delta(i), // this is line 32...
                                      is_raw_mouse_button_pressed(i, 0), is_raw_mouse_button_pressed(i, 1), is_raw_mouse_button_pressed(i, 2));

emit mouseCoord(get_raw_mouse_x_delta(i), get_raw_mouse_y_delta(i), // this is line 32...
                                      is_raw_mouse_button_pressed(i, 0), is_raw_mouse_button_pressed(i, 1), is_raw_mouse_button_pressed(i, 2));

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I have searched the forum and found several issues quite like mine, but not enough to help me out.