#!/usr/local/bin/perl -w
use strict;
use Tk;

my $line = "";
my $submain = MainWindow->new();
my $status = $submain->Button(-text => 'Click to Clear',
                     -command => sub {$submain->destroy;}
                      );
$status->pack;

my $text1 = $submain->Text ('-width'=>100, 'height'=>20);
$text1->pack(-side => 'left', -fill => 'y');

$text1->insert('end', "start\n");
$text1->pack;

for(my $loop=0; $loop <= 3; $loop++ )
   {   
   sleep 1;  
   print "$loop\n";
            
   if    ( $loop == 1 ) { $line = "$loop case 1\n"; }
   elsif ( $loop == 2 ) { $line = "$loop case 2\n"; }
   else         { $line = "$loop something else\n"; }
            
   $text1->insert('end', "$line");
   $text1->pack;
   }

MainLoop();