I re-arranged the order that the base classes are called and it works... try this:
package Tk::Foon;

use base qw(Tk::Label Tk::Derived); #<= changed order
Construct Tk::Widget 'Foon';

sub ClassInit  
{
  my($class, $mw) = @_;
  $class->SUPER::ClassInit($mw);
}

sub Populate
{
  my($self, $args) = @_;
  $self->SUPER::Populate($args);
  $self->ConfigSpecs('DEFAULT' => [ 'SELF' ]); 
}

[download]
Cheers,
JamesNC

In reply to Re: Tk widget derivation problems by JamesNC
in thread Tk widget derivation problems by anjiro

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