my $file_dialog = Gtk::FileSelection
   ->Class::Chain::new("File Selection Demo")
   ->chain(sub {shift->wrap_ok_button
       ->label("Load")
       ->relief("half")
       ->width(80)
       ->height(50)
       ->signal_connect(clicked => sub {
           print $file_dialog->get_filename()->ret_val, "\n";
       });
   })
   ->chain(sub {shift->wrap_cancel_button
       ->label("Exit")
       ->relief("half")
       ->width(80)
       ->height(50)
       ->signal_connect(clicked => sub{Gtk->main_quit});
   })
   ->set_filename("penguin.png")
   ->signal_connect(destroy => sub{Gtk->main_quit})
   ->show();