my $mw = MainWindow -> new();

my $lb = $mw -> Scrolled("Listbox",

    -scrollbars=>'e' ,
    
) -> pack(

    -side => 'left' ,
    -fill => 'y'
);

foreach my $key ("first" , "second" , "third", "fourth") {
    
    $lb -> insert( 'end', $key );

}

    $lb->activate ( 0 ) ;
    $lb->selectionSet ( 0 ) ;
    $lb->focus;

$lb -> bind ('<Key-Down>', sub {print "Down\n"} );

$mw -> bind ('<Key-Up>', sub {print "\nUP"} );

MainLoop;