Hi, here is a Tk version of what I think you want. I have no idea what Tkx does, but the idea should be the same. 
#!/usr/bin/perl -w
use strict;
use Tk qw/tkinit DoOneEvent exit DONT_WAIT ALL_EVENTS/;
use Tk::JComboBox;

my $mw  = MainWindow->new();

my $combo = $mw->JComboBox(
    -choices => [
        { -name => 'Black', -value => 1 },
        { -name => 'Blue', -value => 2 },
        { -name => 'Green', -value => 3 },
        { -name => 'Purple', -value => 4 },
        'Red',
        { -name => 'Yellow', -value => 5 }
    ]
)->pack;

my $count = 0;
my $timer = $mw->repeat(1000,sub{ $count++; });


while ( Tk::Exists($mw)  ) {
  $mw->DoOneEvent( DONT_WAIT | ALL_EVENTS ); 
  print "$count\n";

  if( $count > 10 ){ $mw->destroy }
}

print "end of gui, press a key to continue\n";

<>;

print "exiting\n";

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In reply to Re: Tkx combobox error on quit by zentara
in thread Tkx combobox error on quit by Anonymous Monk

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