about gtkcombobox

["zhenghe zhang" <zhenghe zhang gmail com>]

Hi all
        I am learning gtk+, Now I have some problem and I hope you help me,
thank you.
        As followed:
        1. the gtkcombobox popups the list, there is background color in the
item when moving the mouse. Now I want to change the background color.(don't
rc file )
        2. eg: I have changed the background color of GtkMenuItem
        Gtk_widget_modify_bg(menuitem,GTK_STATE_SELECTED,&color); it can be
changed the background color, but I don't change the gtkcombobox's
background color.

Thank you 
Best regards
zh