Tk::Derived - Base class for widgets derived from others
=for category Derived Widgets
@ISA = qw(Tk::Derived Tk::Something);
$cw->SUPER::Populate($args);
Tk::Derived is used with perl5's multiple inheritance to override some
methods normally inherited from Tk::Widget.
Tk::Derived should precede any Tk widgets in the class's @ISA.
Tk::Derived's main purpose is to apply wrappers to C<configure> and C<cget>
methods of widgets to allow the derived widget to add to or modify behaviour
of the configure options supported by the base widget.
The derived class should normally override the C<Populate> method provided
by Tk::Derived and call C<ConfigSpecs> to declare configure options.
The public methods provided by Tk::Derived are as follows:
=item -E<gt>ConfigSpecs(-I<key> =E<gt> [I<kind>, I<name>, I<Class>, I<default>], ...)
L<Tk::ConfigSpecs|Tk::ConfigSpecs>