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#!/usr/local/bin/perl -w
use strict;
use Tk;

my $mw = MainWindow->new;

my $bits = pack("b8"x5,
	"........",
	"...11...",
	"..1111..",
	".111111.",
	"........");

$mw->DefineBitmap('increment' => 8,5, $bits);
#   And of course, decrement is the reverse of increment :-)
$mw->DefineBitmap('decrement' => 8,5, scalar reverse $bits);

my $value = 1000;

my $up = $mw->Button(-bitmap => 'increment', -pady => 0, -command => sub { $value++ } );
my $dn = $mw->Button(-bitmap => 'decrement', -pady => 0, -command => sub { $value-- } );
my $en = $mw->Entry(-textvariable => \$value, -justify => 'right', -width => 6);
my $qu = $mw->Button(-text => 'Quit', -command => [destroy => $mw]);

Tk::grid($en,$up);
Tk::grid('^',$dn);
Tk::grid($qu,'-');

MainLoop;