#!/usr/bin/perl
use strict;
use warnings;
use Tk;
use Tk::ProgressBar;

my $percent_done=0;
my $mw = MainWindow->new(-title => 'Processing');

my $Progress = $mw->ProgressBar(
			     -width => 30,
				-from => 0,
				-to => 100,
				-blocks => 50,
				-colors => [
					    0, 'green',
					    50, 'yellow' ,
					    80, 'red',
					   ],
				-variable => \$percent_done
			       )->pack(-fill => 'x');

$mw->Button(-text => 'Go!', -command=> sub {
	      my $i;
	      for ($i =0; $i < 1000; $i++) {
		$percent_done = $i/10;
		print STDOUT "$i\n";
		$mw->update; 
	      }
	    })->pack(-side => 'bottom');

MainLoop();