Tk::Menu::Item - Base class for Menu items

       This OO interface is very new. Using the label as the "key" is a problem for separaror items which  don't
       have  one.  The  alternative  would  be  to use an index into the menu but that is a problem if items are
       deleted (or inserted other than at the end).

       There should probably be a PostInit entry point too, or a more widget like defered 'configure'.

perl v5.40.1                                       2025-04-13                                    Menu::Item(3pm)

       Tk::Menu::Item is the base class from which Tk::Menu::Button, Tk::Menu::Cascade, Tk::Menu::Radiobutton
       and Tk::Menu::Checkbutton are derived.  There is also a Tk::Menu::Separator.

       Constructors are declared so that $menu->Button(...) etc. do what you would expect.

       The "-label" option is pre-processed allowing ~ to be prefixed to the character to derive a "-underline"
       value. Thus

           $menu->Button(-label => 'Goto ~Home',...)

           is equivalent to

           $menu->Button(-label => 'Goto Home', -underline => 6, ...)

       The "Cascade" menu item creates a sub-menu and accepts these options:

       -menuitems
           A  list  of items for the sub-menu.  Within this list (which is also accepted by Menu and Menubutton)
           the first two elements of each item should be the "constructor" name and the label:

               -menuitems => [
                              [Button      => '~Quit', -command => [destroy => $mw]],
                              [Checkbutton => '~Oil',  -variable => \$oil],
                             ]

       -postcommand
           A callback to be invoked before posting the menu.

       -tearoff
           Specifies whether sub-menu can be torn-off or not.

       -menuvar
           Scalar reference that will be set to the newly-created sub-menu.

       The returned object is currently a blessed reference to an array of two items: the  containing  Menu  and
       the 'label'.  Methods "configure" and "cget" are mapped onto underlying "entryconfigure" and "entrycget".

       The  main  purpose  of  the OO interface is to allow derived item classes to be defined which pre-set the
       options used to create a more basic item.

       Tk::Menu::Item - Base class for Menu items

          require Tk::Menu::Item;

          my $but = $menu->Button(...);
          $but->configure(...);
          my $what = $but->cget();

          package Whatever;
          require Tk::Menu::Item;
          @ISA = qw(Tk::Menu::Item);

          sub PreInit
          {
           my ($class,$menu,$info) = @_;
           $info->{'-xxxxx'} = ...
           my $y = delete $info->{'-yyyy'};
          }