#!/usr/bin/perl
use Tk;
use strict;

my $mw = MainWindow->new;
my @color = qw/red lightgray/;
my $bits = pack("b8"x8,
"...11...",
"..1111..",
".111111.",
"11111111",
"11111111",
".111111.",
"..1111..",
"...11...",);

$mw->DefineBitmap('indicator' => 8,8, $bits);

my $label = $mw->Label(-bitmap=>'indicator', -fg=>'red')->pack;

$mw->repeat(500,sub{$label->configure(
                               -fg=>$color[0]);
                               @color=reverse(@color);
 });

MainLoop;