[perl-win32-gui-users] constants + OO + external file generates cleanup error message

[Leif Andersson]

I had the, maybe bad, idea of putting up a kind of "framework", so I
could manage my windows definitions in external separate files.

In its simplest form it works as expected:
<code>
#!/usr/bin/perl -w
use strict;
use Win32::GUI qw(WS_SYSMENU);

my $handle = do 'mainw.gui' ;
$handle->Show;
Win32::GUI::Dialog();
</code>

But I also wanted to build this around some objects.
So I added a package returning an object.
Now it still appeared to work, but on exit I get some error messages
like:

    (in cleanup) Can't call method "DELETE" on an undefined value ...

First, I can't understand what the undefined value is.
(But it clearly has to do with the exported constants.)
Second - can I just disregard this message? Should I do it in some other
way? Or should I drop the whole idea?

The version I am using is ActiveState Perl 5.8.8 build 819
with Win32::GUI version 1.0304

Some code to show the error:

#!/usr/bin/perl -w
package NC::GUI;

use strict;
use Carp;
#use Win32::GUI();
# uncomment line above and
# out-comment the line below to make error disappear
use Win32::GUI qw(WS_SYSMENU); # any constant will do

sub new {
    my $class = shift;
    $class    = ref($class) || $class;
    my $self  = {};
    bless $self, $class;
    return $self;
}

sub read_form {
    my ($self, $filename) = @_;

    # read a file containing definitions for a window        
    $self->{form}->{$filename}->{window} = do $filename ;
}

sub run {
    my ($self, $name) = @_;
    $self->{form}->{'mainw.gui'}->{window}->Show;
    Win32::GUI::Dialog();
}
1;

#-----------------------------------------------------------------------
--
package main;
use strict;

my $obj = new NC::GUI;
$obj->read_form('mainw.gui');
$obj->run();

__END__

#-- And the external file mainw.gui contains:

$mainW = new GUI::DialogBox(
        -name     => "mainWindow",
        -title    => "Our main window",
        -left     => 100, 
        -top      => 100, 
        -width    => 130,
        -height   => 230,
);

$mainW->AddButton(
        -name       => "mainButton1", 
        -text       => "Dummy",
        -valign     => "center",
        -left       =>  70,
        -top        => 164,
        -width      =>  40,
);

# return handle
$mainW;

#--- end of mainw.gui ---


Thanks for any insights,

Leif