Thanks for the help. Using $mw->destroy worked in exiting the MainLoop. However, I have a different issue now. Somehow, after I select my items and exit the menu, all the items listed get added regardless if I check them or not. Here's the code I'm using:

use strict;
use warnings;
use Tk;
open(INFILE,"d1528235.txt") or die "could not open file for reading!\n
+";
open(OUTFILE, '>forecast.txt') or die "Cannot open forecast.txt: $!";


while(<INFILE>){
  if (m/^\s*$/) { next; }
  chomp $_;
  my @fields = split(/\  /,$_);
  my @output;
  foreach my $field(@fields){
    if($field =~ /^\*?[ABMQRWY][A-Z0-9]{4}235 / ){
      push @output,$field;
      
  }

 #     print OUTFILE "$_\n";
    }
  
  if (@output) {
    my $line = join('',@output);
    print "$line\n";
    print OUTFILE "$line\n";
  }
}

my $mw = MainWindow->new;
$mw->geometry("300x500");
$mw->title("Unforecasted Jobs");

my $check1 = 'NOT CHECKED';
my $check2 = 'NOT CHECKED';
my $check3 = 'NOT CHECKED';
my $check4 = 'NOT CHECKED';
my $check5 = 'NOT CHECKED';
my $check6 = 'NOT CHECKED';
my $check7 = 'NOT CHECKED';
my $check8 = 'NOT CHECKED';

my $check_frame = $mw->Frame()->pack(-side => "top");
$check_frame->Label(-text=>"Jobs That Do Not Forecast")->pack(-side =>
+ "top")->pack();
my $job = "18L";
my $chk1 = $check_frame->Checkbutton(-text => '18-Letters',
                                     -variable => \$check1,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+(),
                                     -command => print OUTFILE "$job\n
+";

my $job2 = "07O";
my $chk2 = $check_frame->Checkbutton(-text => '07-Orders',
                                     -variable => \$check2,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+(),
                                     -command => print OUTFILE "$job2\
+n";

my $job3 = "36L";
my $chk3 = $check_frame->Checkbutton(-text => '36-Letters',
                                     -variable => \$check3,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+();
                                     -command => print OUTFILE "$job3\
+n";
                                     
my $job4 = "38L";
my $chk4 = $check_frame->Checkbutton(-text => '38-Letters',
                                     -variable => \$check4,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+(),
                                     -command => print OUTFILE "$job4\
+n";

my $job5 = "11O";
my $chk5 = $check_frame->Checkbutton(-text => '11-Orders',
                                     -variable => \$check5,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+(),
                                     -command => print OUTFILE "$job5\
+n";

my $job6 = "99L";
my $chk6 = $check_frame->Checkbutton(-text => '99-Letters',
                                     -variable => \$check6,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+();
                                     -command => print OUTFILE "$job6\
+n";
                                     
my $job7 = "21L";
my $chk7 = $check_frame->Checkbutton(-text => '21-Letters',
                                     -variable => \$check7,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+(),
                                     -command => print OUTFILE "$job7\
+n";

my $job8 = "23L";
my $chk8 = $check_frame->Checkbutton(-text => '23-Letters',
                                     -variable => \$check8,
                                     -onvalue => '    ADDED',
                                     -offvalue => 'NOT CHECKED')->pack
+(),
                                     -command => print OUTFILE "$job8\
+n";

my $button_frame = $mw->Frame()->pack(-side => "bottom");
my $ok_button = $button_frame->Button(-text => 'OK',
                                       -command => \&check_sub)->pack(
+-side => "left");
my $exit_button = $button_frame->Button(-text => 'Exit',
                                        -command => sub{$mw->destroy})
+->pack(-side => "right");

sub check_sub {
  my $check_msg = "Check #1: $check1\nCheck #2: $check2\nCheck #3: $ch
+eck3\nCheck #4: $check4\nCheck #5: $check5\nCheck #6: $check6\nCheck 
+#7: $check7\nCheck #8: $check8\nCheck #9: $check9\nCheck #10: $check1
+0\nCheck #11: $check11\nCheck #12: $check12\nCheck #13: $check13\nChe
+ck #14: $check14\n,Check #15: $check15\nCheck #16 $check16";
  $mw->messageBox(-message => "Check Button Summary:\n$check_msg", -ty
+pe => "ok");
}

MainLoop;

my $var =`crossref.pl`;

[download]

In reply to Re^3: Code after MainLoop; Tk by PerlCowboy
in thread Code after MainLoop; Tk by PerlCowboy

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