my $box = Gnome2::Canvas::Item->new ($root, 'Gnome2::Canvas::Rect',
                                     x1 => 10, y1 => 5,
                                     x2 => 150, y2 => 135,
                                     fill_color => 'red',
                                     outline_color => 'black');
$box->lower_to_bottom;
$box->signal_connect (event => sub {
        my ($item, $event) = @_;
        warn "event ".$event->type." on $box\n";
});