#!/usr/bin/perl

use strict;
use warnings;
use Tk;
use Tk::ProgressBar;

my $percent_done;

my $mw = MainWindow->new( -title => 'ProgressBar example' );
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 {
        for ( my $i = 0 ; $i < 1000 ; $i++ ) {
            $percent_done = $i / 10;
            print "$i\n";
            $mw->update } } )->pack(-side => 'bottom');
MainLoop;