bind up and down keys in a tk listbox

[lepetitalbert]

Hello dear Monks,

I'm totally unable to bind the up and down keys to move in a tk listbox

I found a few examples but none of them worked.

This is a simple test script :

use Tk;

my $mw = MainWindow -> new();

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

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

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


foreach my $key ("a" , "b" , "c") {
    
    $lb -> insert( 'end', $key );

}

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

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

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


MainLoop;

It seems I have to bind the key to the main window and not to the listbox, is this right ?

Thanks for any help or example.

Have a nice day.

[reasonablekeith]

If you want the up/down keys to control the listbox then I think you need to manage the focus. Adding an explict call in your code as follows enables these keys.

foreach my $key ("a" , "b" , "c") {
    $lb -> insert( 'end', $key );
}
$lb->activate ( 0 ) ;
$lb->selectionSet ( 0 ) ;
$lb->focus();

I'm _far_ from being a Tk expert, so I'd advise you to check out Tk::Focus docs for yourself.

[lepetitalbert]

Thank you reasonablekeith, cannot belive I missed this :)

Works perfect.

Have a nice day.