use strict;
use warnings;
use Tk;

my @array = ("File1.txt", "File2.txt", "File3.txt");

my $main = MainWindow->new ();
while (@array)
  {
  my $name=pop @array;
  $main->Button
    (
    -text => "Open $name",
    -command => sub{`notepad $name`}
    )->pack();
  }

MainLoop;