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

my $mw = tkinit;

my $topframe = $mw->Frame()->pack(-fill=>'x' );
my $mainframe = $mw->Frame()->pack(-expand=>1, -fill=>'both' );

my $exit_b = $topframe->Button(-text=>'Exit',
            -command=> sub{ exit } )->pack(-side => 'right', -padx=>20);

my @array1=();
my $l1 = $mainframe->Scrolled('Listbox',
              -listvariable => \@array1,
              -scrollbars => 'ose')
              ->pack( -side => 'left', -expand=>1, -fill=>'both' );

my @array2=();
my $l2 = $mainframe->Scrolled('Listbox',
              -listvariable => \@array2,
              -scrollbars => 'ose')
              ->pack( -side => 'left', -expand=>1, -fill=>'both' );

my @array3=();
my $l3 = $mainframe->Scrolled('Listbox',
              -listvariable => \@array3,
              -scrollbars => 'ose')
              ->pack( -side => 'left', -expand=>1, -fill=>'both' );

&update;

my $repeater =  $mw->repeat(5000,\&update);

MainLoop;

sub update {

   foreach my $arr_ref (\@array1,\@array2,\@array3){
         
              @$arr_ref = ();
              for (1..100){
               push @$arr_ref, rand 10000;
               #sort @$arr_ref;  #do a text sort on filenames
               $mw->update;
              }
    }

}