It sounds like what you want is an app with two listboxes where an event in listbox1 activates something in listbox2. If this is correct, test the following code. Pressing 'insert' in the left box will add an item to the box on the right. Pressing 'delete' in the left box will remove the last item from the box on the right. Granted its a quick hack, but it will get you started.

#!/usr/bin/perl
#
use Tk;
use strict;

my ($mw, $lb1, $lb2);
my $count = 1;

$mw = MainWindow->new();

$lb1 = $mw->Listbox()->pack(-side => 'left');
$lb1->insert('end', 'insert','delete');
$lb1->bind('<<ListboxSelect>>' => \&sub1);
$lb2 = $mw->Listbox()->pack(-side => 'left');

MainLoop;
exit;

sub sub1 {
   my $sel = $lb1->curselection;
   if( $sel->[0] == 0 ) {
      &sub2;
   } else {
       &sub3;
   }
}

sub sub2 {
    $lb2->insert('end', "inserting $count");
    $count++;
}

sub sub3 {
    $lb2->delete('end');
    $count--;
}
[download]

hope this helps,

davidj