Is there a way to make a combo box pulldown expand with displaying fixed number of items

[Igor Korot <ikorot earthlink net>]

Hi, ALL,
Is there a way to make a combo box not to drop to cover the
screen from top to bottom?

There is the function 
AtkObject *gtk_combo_box_get_popup_accessible(GtkComboBox *combo_box);

that returns object corresponding to the popup.
But when I tried to call the size function on this object,
it says there is no such function.

Also, clicking on the "AtkObject" will bring the following
error:

"404 Not Found. The requested URL /usr/share/gtk-doc/html/atk/AtkObject.html
was not found on this server."

I believe that this is a bug on the site...

Thank you.