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


my $lst_properties;
my $chk_options;
my $chkoptions;
my $MainWindow;

&maingui;

sub maingui {

    $MainWindow = MainWindow->new(-title=>'Listbox');

my @properties = ("People","Animals","Aliens","Meat",
            "Fruit","Vegies","Dairy","Pultry",
            );

    $chk_options = $MainWindow -> Checkbutton ( -anchor=>'nw',
            -justify=>'left',-relief=>'flat',
            -indicatoron=>1,-text=>'Additional Criteria',
            -variable=>\$chkoptions, -state=>'normal',
            -command=>\&Additional_Criteria
            ) -> grid(-row=>1,-column=>0,-pady=>5);

    $lst_properties= $MainWindow -> Scrolled ( 'Listbox',
            -selectmode=>'single', 
            -relief=>'sunken',
            -scrollbars=>'osoe',
            -width=>50,
            -listvariable=>\@properties,
            -state=>'disabled'
            );


    $lst_properties -> grid(-row=>5,-column=>1,-pady=>3);
   
 MainLoop;
}


sub Additional_Criteria
{
 #code her to test if check box is selected or not

   if ($chkoptions) {
      print "Enable\n";
      $lst_properties->configure(-state=>'normal');
   }
   else {
      print "Disable\n";
      #Code here to DISABLE ListBox
    $lst_properties->configure(-state=>'disabled');
   }
}
[download]

Hello Zentara,
This worked! I definatly like the idea of "listvaraibles".
Thanks for your assistance

Yeah, the nice thing about an array as a list variable, is you can just modify the array any way you want, and it will be automatically updated in the listbox. So you can sort, remove, or splice elements into the array at any position, and the list will show it. Trying to modify the list itself is quite abit trickier, since you need to deal with the indices of the listbox.

---

I'm not really a human, but I play one on earth. Cogito ergo sum a bum

2. When I click the checkbox, how do I enable the listbox so that the user is now able to select items from the list?

With $listbox->configure(-state => 'normal'); in the event handler of that checkbox.

I tried adding the following in the subroutine, but it had no effect

sub Additional_Criteria
{
 #code her to test if check box is selected or not

   if ($chkoptions) {
      print "Enable\n";
      $lst_properties->configure(-state=>'normal');
   }
   else {
      print "Disable\n";
      #Code here to DISABLE ListBox
   }
}
[download]

use strict;
use warnings;
use Tk;
my $w = MainWindow->new();
my $l = $w->Listbox()->pack();

for (qw(foo bar baz)){
    $l->insert('end', $_);
}

# disable it afterwards

$l->configure(-state => 'disabled');

MainLoop;
[download]

I don't see why $l->configure(-state => 'normal'); or $l->configure(-state => 'disabled'); shouldn't work for enabling/disabling the box. Try to insert a few prinit statements to verify that you're actually executing the code you think you are executing.

Hello moritz,
That was it. I overlooked, "If the listbox is disabled then items may not be inserted or deleted". I implemented suggestion to make it normal, add the list and then disable it.
Thanks again

Well a single or double click on an enabled list doesn't do much, until you bind the double click

$lb -> bind("<Double-Button-1>",\&display);

sub display {
  $selected = $lb -> get($lb -> curselection);
  $message = "You selected: $selected \n";
  print "you chose $selected\n";
  $lb->selectionClear(0, 'end');
}
[download]