#!/usr/bin/perl

use strict;
use warnings;
use Tk;

my $main = MainWindow->new;

my $text = $main->Scrolled('Text', 
			   -width=>'50'
			  )->pack;

my $button = $main->Button(-text=>'next',
			  )->pack;

$button->bind('<ButtonPress>', \&one);

MainLoop;

sub one
  {
    my $talk="One! Click for two.\n";
    $text -> insert('1.0',"$talk");
    $button->bind('<ButtonPress>', \&two);
  }

sub two
  {
    my $talk="One! Click for three.\n";
    $text -> insert('1.0',"$talk");
    $button->bind('<ButtonPress>', \&three);
  }

sub three
  {
    my $talk="One! Click for one.\n";
    $text -> delete('1.0', 'end');
    $text -> insert('1.0',"$talk");
    $button->bind('<ButtonPress>', \&one);
  }