I need to display a message box after a user clicks on a button. For some reason, I can't seem to get this code to work. Any help is much appreciated.

The text "before\n" is printed, but the dialog is not displayed.

#! /usr/bin/perl -w
#

use strict;
use warnings "all";
use Tk;
use Tk::Dialog;

our $mw = new MainWindow; 
my $f_select = $mw->Frame( -bd=>2, -relief=>'groove') ->pack(-side=>'l
+eft', -fill=>'y');
my $f_refresh = $f_select->Frame() ->pack(-side=>'bottom', -fill=>'x')
+;
$f_refresh->Button(-text => 'Test', -command => sub {displayMsg()}) ->
+pack(-side=>'left');

# This one works.
$mw->Dialog(-title => "Test", -text => "My test Message", -bitmap=>'qu
+estion', -buttons => ['Ok'])->Show();

MainLoop;

exit; # Should never actually get here.

sub displayMsg {
    print "before\n";
    # for some reason, Dialog() does not work from this context.  
    # $mw->Dialog(-title => "Error", -text => "My Error Message", -bit
+map=>'error', -buttons => ['Ok'])->Show();
    my $dialogWindow = $mw->Dialog(-title => "Error", -text => "My Err
+or Message", -bitmap=>'error', -buttons => ['Ok']);
    $dialogWindow->Show();
    
    # neither does messageBox :-(
    #my $answer => $mw->messageBox(-title => 'Please Reply', 
    # -message => 'Would you like to continue?', 
    # -type => 'YesNo', -icon => 'question', -default => 'yes');
    print "after\n";
}

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In reply to Can't get Dialog or messageBox to work from button by SwaJime

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