#!/usr/bin/perl 
use warnings;
use strict;
use Tk;

my $mw = new MainWindow();

# 1. Entry
$mw->Label(-text=>'Label 1: ')->pack;
my $e1 = $mw->Entry()->pack;

# 2. Entry
$mw->Label(-text=>'Label 2: ')->pack;
my $e2 = $mw->Entry()->pack;

# Exit-Button
$mw->Button(-text=>'End', -command=>sub {exit} )->pack;

# -- Define Bindings --
# -- "Do play a Beep when <Alt-e> ist pressed - except
# -- for: focus is on $e1"

$mw->bind("<Alt-e>", sub { print "\a"; print "beep\n"; } );
$e1->bind("<Alt-e>", sub { } );
my (@bt) = $e1->bindtags;
print "before-> @bt\n";

#In order to change the beep in the entry, without
#affecting the $mw beep, you must change the bindtags
#for $e1. Remove the toplevel and 'all' specs, or at 
#least move them to the end of the bind order.  

$e1->bindtags([$e1, ref($e1)]);
# or, depending on your requirements...
#$e1->bindtags([$e1, ref($e1), $e1->toplevel, 'all']);

(@bt) = $e1->bindtags;
print "after->  @bt\n";

MainLoop;

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Can I do something like below ? Will it serve my purpose ?

What happens when you try? Yes, that should effectively unbind, and if you're using the latest Tk

You could always weaken before giving it to Tk

#!/usr/bin/perl --
use strict; use warnings;
use Tk;
use Scalar::Util qw/ weaken /;
my $mw = tkinit;
my $b  = $mw->Button->pack;

$b->bind(
    q/<1>/,
#~  sub { $self->onEnter($label, $obj_A) ; },
    [
        sub {
            warn qq/@_/;
            my $button = shift;
            my ( $self, @rest ) = @_;
            $self->onEnter(@rest);
        },
        weaken( $self ),
        weaken( $label ),
        weaken( $obj_A ),
    ]
);
MainLoop;
__END__
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