I always think i've found something that doesn't work because it doesn't work for me and then i learn better. Hopefully nothing has changed!

Today's frustration is using 'active' as an index in Tk::Menu.

I have a menu which is a list of files, and i want to bind keys so that multiple actions are available when an entry is active, distinct from the command which would be invoked by clicking the entry. I thought the way to do this would be (something like) this: 

#!/usr/bin/perl

use strict;
use Tk;

my $MW = MainWindow->new;
my $menu = $MW -> Menu(-type=>'menubar',-tearoff=>0);
$MW -> configure(-menu=>$menu);
$MW -> bind("<Key-F1>"=>[\&printentry]);

my $MM = $menu -> cascade(-label=>'menu',-underline=>0,-tearoff=>0);
my $one = $MM -> command(-label=>'one',-command=>sub{});
my $two = $MM -> command(-label=>'two',-command=>sub{});
my $three = $MM -> command(-label=>'three',-command=>sub{});

MainLoop;

sub printentry {
        my $whM = $menu->entrycget('active','-label');
        print "active:$whM\t";
}

[download]
The problem:


Using a key would seem to be the only way to go, because if you move off the menu and click anything the menu disappears or their is no real active entry. Unfortunately, the binding only works when the first level cascade is active (highlighted), before it is clicked, and never when any cascade is in use. More unfortunately, 'active' never returns a value even if "one" is highlighted (active).

Considering this, the use of 'active' as the index, which is documented, can never actually apply (except on "one" "two" "three"; but then it doesn't...) Ie, if you substitute '0' or '1' or '2' for 'active', you will get a value. nb. if it did work, i believe ->configure could be used to get the same information from the active cascade (entrycget cannot) SO PLEASE DON'T TELL ME "$menu isn't $MM" ETC.

In reply to Tk! (entrycget w/ 'active') by halfcountplus

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