use Tk;

my $mw = MainWindow->new;
my $text = $mw->Text->pack;

my $bFrame = $mw->Frame->pack(qw/-side bottom/);

$bFrame->Button(
   -text => "Check Text",
   -command => sub {
      if ($text->index('end - 1c') == 1) {
         print "Text is empty\n";
      } else {
         print "Text contains data\n";
      }
})->pack(qw/-side left/);

$bFrame->Button(
   -text => "Clear Text",
   -command => sub {
      $text->delete("1.0", 'end');
})->pack(qw/-side left/);

MainLoop;