Suppose that I want to adapt an existing class to my immediate needs, by adding some methods, right in my quick and not-too-dirty script.

I can see two ways, illustrated below, with Tk::HList::addrow() and updaterow().

Please comment on pros and cons, and on other possible ways to achieve this.

Rudif

#!/usr/bin/perl

use strict;
use Tk;
use Tk::Label;
use Tk::HList;


sub Tk::HList::addrow {
    my ( $self, $row, $text ) = @_;
    $self->add($row);
    $self->itemCreate( $row, 0, -text => $text );
}

package Tk::HList;

sub updaterow {
    my ( $self, $row, $text ) = @_;
    $self->itemConfigure( $row, 0, -text => $text );
}

package main;

my @items;
my $selectedrow = 0;

my @text = qw ( AAA BBB CCC DDD EEE FFF );

my $mw = MainWindow->new();

my $frm1 = $mw->Frame()->pack(
    -side   => 'top',
    -anchor => 'w'
);

my $frm2 = $mw->Frame()->pack(
    -side   => 'top',
    -anchor => 'w'
);

my $but1 = $frm1->Button(
    -text    => "reverse",
    -command => \&revers,
    -width   => 20,
)->pack( -side => 'left' );

my $label = $frm2->Label(
    -width => 5,
    -text  => $selectedrow
)->pack( -side => 'left' );

my $but2 = $frm2->Button(
    -text    => "incr",
    -command => \&incr,
    -width   => 15,
)->pack( -side => 'left' );

my $hlist = $mw->HList(
    -itemtype   => 'text',
    -height     => 20,
    -separator  => '/',
    -selectmode => 'single',
    -browsecmd  => sub {
        $selectedrow = shift;
        $label->configure( -text => $selectedrow );
        print "$selectedrow\n";
    }
)->pack;

add();

MainLoop;



sub add {
    foreach my $i ( 0 .. $#text ) {
        $hlist->addrow( $i, $text[$i] );
        push @items, $i;
    }
}

sub refresh {
    foreach my $i ( 0 .. $#text ) {
        $hlist->updaterow( $i, $text[$i] );
    }
}

sub incr {
    ++$text[$selectedrow];
    refresh();
}

sub revers {
    @text = reverse @text;
    refresh();
}
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