use strict;
use Tk;
use Tk::NoteBook;

my $mw = MainWindow->new;
my $notebook = $mw->NoteBook()->pack(-expand=>1, -fill =>'both', -side=>'right');

$mw->Button(-text=>'Click me', -command=> sub {AddAPage(\$notebook)})->pack();

MainLoop;

sub AddAPage {
  my $n = shift;
  
  my @pages = $$n->info('pages');
  my $pageNumber = scalar(@pages)+1;
  $$n->add($pageNumber, -label=>"hello $pageNumber");
  AddPageContents($n,$pageNumber);
}

sub AddPageContents {
  my $n = shift;
  my $page = shift;

  use Data::Dumper;
  print Dumper($$n);
  
  $$n{_pages_}{$page}->Button(-text=>'Hi')->pack();
}


##</code><code>##

Tk::Error: Not a HASH reference at try.pl line 30.
 main::AddPageContents at try.pl line 30
 main::AddAPage at try.pl line 20
 main::__ANON__ at try.pl line 10
 [\&main::__ANON__]
 Tk callback for .button
 Tk::__ANON__ at /usr/local/ActivePerl-5.6/lib/site_perl/5.6.1/sun4-solaris-thread-multi/Tk.pm line 217
 Tk::Button::butUp at /usr/local/ActivePerl-5.6/lib/site_perl/5.6.1/sun4-solaris-thread-multi/Tk/Button.pm line 111