use strict;
use warnings;
use Tk;

my $mw = MainWindow -> new;
$mw -> minsize (qw(600 400));
$mw -> withdraw;

for (1..10) {
	my $button = $mw -> Label (-text => "Label $_") -> pack;
}

$mw -> update;
$mw -> idletasks;
$mw -> Popup(
			-overanchor => 'c',
			-popanchor => 'c',
			);
MainLoop;