Maybe there is something amiss in the button callback? I mean if you are doing something like this:

$detailLog->insert ('end', $_);
# or $detailLog->insert ('end', $string);
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$detailLog->delete("1.0", 'end');
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Update: A simple text window with "clearing the text" button is shown below. A couple of other Tk options are also demo'ed. I use 'ROText' instead of 'Text' to show that this is "Read Only". Try it!

This "enable" and "disable" stuff will usually be ok, but there will be a short interval of time where the user can modify the displayed window.

I have one application where I just don't care whether or not the user modifies the text window and I don't use ROText. I'm not reading that result and modifying the database. The user can add notes, and formatting characters before doing a "copy and paste" to another application. Fine with me!

Anyway, what is the problem with $detail_log->delete("1.0", 'end');?

#!/usr/bin/perl -w
use strict;

use Tk;
use Tk::Frame;   #optional - may be needed for an .exe 
use Tk::ROText;  #optional - may be needed for an .exe

my $mw = MainWindow->new;
my $f_menu_dialog = $mw->Frame()->pack(-side=>'top',-fill=>'x');
$f_menu_dialog->Button( -text     =>"Clear All text",
                        -command  => \&Clear_all_text,
                      )->pack(-side=>'left');
                       
                       
my $f_text = $mw->Frame( -relief      => 'groove', 
                         -borderwidth => '4',
                       )->pack
                             (   -expand => 1, 
                                 -side   => 'top',
                                 -fill   => 'both', 
                             );

my $detail_log = $f_text->Scrolled('ROText', 
                                    -scrollbars => 'e')->pack;


foreach ("blah\n", "more blah\n", "yet more blah\n")
{
   $detail_log -> insert('end', $_);
}

MainLoop();

sub Clear_all_text
{
    $detail_log->delete("1.0", 'end'); 
}
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