hello everyone

I have some problems with QPopupMenu :
source code :
QWidget * tabindex ;
tabindex =new QWidget (this ,"tabindex ") ;
QPopupMenu *home ;
home =new QPopupMenu (tabindex,"home " );
home ->insertItem ("hello world ",-1) ;

but the menu item don't show in tabindex ,must the popupmenu add in QMenuBar

another question :
The QMenuBar class provides a horizontal menu bar,how I could show menu items like the left column in the menu of XP(double columns menu ) ?

thanks