use strict;
use warnings;

use Tk;

my $mw    =
    tkinit ();
my $frame    = $mw-> Frame (-relief => 'groove', -bd => 2)-> pack ();

my $text    = $mw-> Text ()->pack (-expand => 1);

my $widget    =
    $frame-> Label (
        -text    => "Hier ist ein Widget!",
    )->pack;
my $widget_on    = 1;    
    
my $button    = 
    $mw-> Button (
        -text     => "Widget an/ausschalten",
        -command    => sub {
            if ($widget_on == 0){
                $frame-> pack (-before => $text);
                $widget_on    = 1;
            }
            else{
                $frame-> packForget ();
                $widget_on    = 0;
            }
        }
    )-> pack;

Tk::MainLoop ();