how to make a pixmap widget get the key_press_event?

[huzheng <forlinux 263 net>]

i use event_box to contain the pixmap widget,and
gtk_widget_set_events (event_box, GDK_KEY_PRESS_MASK);
gtk_signal_connect (GTK_OBJECT (event_box), "key_press_event",
                    GTK_SIGNAL_FUNC (on_test_pressanykey_keypress), this);
but i find the event_box can't get the key_press_event too.

thank you for reply :)