use Tk;
$mw = MainWindow->new;
# Create necessary widgets
$f = $mw->Frame->pack(-side => 'top', -fill => 'x');
$f->Entry(-textvariable => \$filename)->pack(-side => 'left',
-anchor => 'w', -fill => 'x', -expand => 1);
$f->Button(-text => "Exit", -command => sub { exit; } )->
pack(-side => 'right');
$t = $mw->Scrolled("Text")->pack(-side => 'bottom',
-fill => 'both', -expand => 1);
MainLoop;