use warnings;
use strict;
use Tk;

my $page = MainWindow->new;
$page->geometry('600x200');

# Create a frame ...
my $suite_fr = $page->Frame->pack(-expand => 1, -fill => 'both');

# Add a label to the frame
$suite_fr->Label(-text => 'Suite:')->pack(-side => 'left');

# create a Scrolled Listbox
my $suite_lb = $suite_fr->Scrolled( 'Listbox',
	-exportselection  => '0',
	-height           => '7',			
	-scrollbars       => 'e',
	-selectbackground => 'gray80',
	-selectforeground => 'black',
	-selectmode       => 'extended'
)->pack(-side => 'left');

my $button = $page->Button(
    -text => '  Fill  ',
    -command => sub{ fillbox($suite_lb) },
)->pack;

MainLoop;

sub fillbox{
    my $self = shift;
    $self->packPropagate(1);

    my @list = 'X' x rand 80;

    # Populate the ListBox with the valid suites
    $self->insert(0, @list);

    $self->Subwidget("listbox")->configure(-width => 0);
}