You said you were using Tcl/Tk, but it looks like a plain Perl/Tk script to me. In any event, your code problem almost certainly stems from having multiple new MainWindow and multiple MainLoop declarations. In Perl/Tk, as in the Highlander, there can only be 1 :-)

The first MainWindow you declare is fine, but all those following ones should be converted to Toplevel windows, which exist under the the single MainLoop of the first MainWindow declared.

Here is a simple usage of Toplevel 

#!/usr/bin/perl

use strict;
use warnings;
use Tk;

my $mw = MainWindow->new;
$mw->Label(-text => 'Main Window')->pack;
$mw->Button(
-text => 'Quit Main',
-command => sub{$mw->destroy},
)->pack;

my $top = $mw->Toplevel;
$top->Label(-text => 'Top level Window')->pack;
$top->Button(
-text => 'Exit Top level',
-command => sub{$top->destroy},
)->pack;
$top->transient($mw);

MainLoop;

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Old Perl Programmer Haiku ................... flash japh

In reply to Re^3: Error Not a tk object / Problems with multiple files by zentara
in thread Error Not a tk object / Problems with multiple files by reaper9187

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