Hiding Mac OS system menu in Qt

I know it not a big deal, but when you work with full screen application system menu pops up when you move mouse on the top, so here is a hack that solve this problem, I use it in main.cpp

put this in header

#ifdef Q_WS_MACX
#include 
#endif

and this in main procedure:

int main(int argc, char *argv[])
{
QApplication a(argc, argv);

MainWindow w;

w.show();

#ifdef Q_WS_MACX
HideMenuBar();
#endif

return a.exec();

//other code
}

thats it :) I hope it will help