Ok, here is the solution. First, you are using the same textvariable reference and that is why the box pops up, use a second one and that issue goes away. The other problems are caused by the fact that you keep creating instances of dialog boxes and JCombo's. Create a single instance, and then use the Show() method in your CallDialog sub. Here is your version hacked up to work: 
use strict;
use warnings;
use Tk;
use Tk::JComboBox;
use Tk::Dialog;

my $form;
my %choices = (  'a'=>1,  'b'=>2,  'c'=>3 );
my $selected_1 = "a";
my $selected = "a";
my $dialog;
my $testbox1;
my $testbox2;

CreateMainForm();
MainLoop();


sub CreateMainForm
{
    $form = MainWindow->new();
    $form->title("Test for JComboBox Problem");
    $testbox1 = $form->JComboBox(  -textvariable=>\$selected_1,
    -validate=>'match', -mode=>'editable',
    -relief=>'sunken',  -highlightthickness=>0,
        );
    for my $x(keys %choices) { $testbox1->addItem("$x"); }
    $testbox1->pack(-side=>'left');    
    my $button = $form->Button(  -text=>"Dialog",
    -command=>sub{CallDialog($testbox1)}
            )->pack(-side=>'right');
    
    $dialog = $form->Dialog (  -title=>"Part2 of test",
    -buttons=>["Submit","Cancel"],-default_button=>"Submit"
            );
    $testbox2 = $dialog->JComboBox(-textvariable=>\$selected,
    -validate=>'match',-mode=>'editable',
    -relief=>'sunken',-highlightthickness=>0 
            );
for my $x(keys %choices) { $testbox2->addItem("$x"); }

    $testbox2->pack(-side=>'left');
}

sub CallDialog
{
    $testbox1->configure(-state=>'disabled');
    my $retval = $dialog->Show( 
    -popover=>$form, -overanchor=>'c', -popanchor=>'c');

    if($retval eq "Cancel")
    {
        $testbox1->configure(-state=>'normal');
    }
    elsif($retval eq "Submit")
    {
        $testbox1->configure(-state=>'normal');
    $testbox1->setSelected($selected ); #(optional?)
    }
 
}

[download]


Cheers,
JamesNC

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

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