Lines 566-569 of my version of JComboBox.pm is 
  my $mode = $cw->cget('-validate');
  if ($mode =~ /match/) {
    $cw->configure(-validate => 'none');
  }

[download]
$mode must be undefined and as a result, issues that warning.

The code can be re-written to check before it tries to regex. You can change the code in the module to something like: 
  my $mode = $cw->cget('-validate');
  if (defined $mode && $mode =~ /match/) {  # <== change
    $cw->configure(-validate => 'none');
  }

[download]
And that will fix the warning. If you are using -validate make sure you aren't pointing to an undef value. All the code does is set -validate to 'none' if it is set to 'match'. It is in the SetSelectedIndex subroutine.

JamesNC

In reply to Re^5: Help with JComboBox by JamesNC
in thread Help with JComboBox by ChrisR

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