#!/usr/bin/perl
use Tk;

my $mw = MainWindow->new();

my $opt = $mw->Optionmenu(
        -options => [[jan=>1], [feb=>2], [mar=>3]]
               )->pack;
#$opt->configure(-indicatoron => undef); 

my $button = $mw->Button(
        -text => 'Remove Indicatoron',
        -command => sub{ $opt->configure(-indicatoron => undef);   }
)->pack;

MainLoop;