Try with:
$f_refresh->Button(-text => 'Test', -command => sub { &displayMsg()})-
+>pack(-side=>'left');

[download]
Call all your functions in Tk with the & or \& prefix if they are defined after their call. Perl can't find them. ;)

Edit
Some call examples:

Here inside an anonymous subroutine: end_automode and ping_site are called. 
$update_bttn = $button_f->Button(-text => "Update",
                 -state => 'disabled',
                 -command => sub { &end_automode;
                           &ping_site });

[download]
Here a direct call to the subroutine do_automode, bind to the command. 
$automode_bttn = $button_f->Button(-text => "Start Automode",
                   -command => \&do_automode);

[download]
Rem: end_automode, ping_site, do_automode are defined after their calls.

In reply to Re: Can't get Dialog or messageBox to work from button by hotchiwawa
in thread Can't get Dialog or messageBox to work from button by SwaJime

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