use Tk;
use strict;

my $mw = MainWindow->new;
$mw->title("Test");

my $frame = $mw->Frame(-bd => 2)->pack;
$frame->Button(
   -text => 'Exit',
   -command => sub { exit })->pack(-side => 'left');

$frame->Button(
   -text => 'Excute', 
   -command => \&execute)->pack;

my $text = $mw->Scrolled("Text",
   -scrollbars => 'oe')->pack(-side => 'bottom');

MainLoop;

sub execute {
    foreach my $b (1 .. 5 ) {
    sleep 2;
    displayText($text,"$b: Display me\n");
    }    
}        

sub displayText {
    my ($text,$output) = @_;
    $text->insert('end',$output);
    $text->see('end');
}