#!/usr/bin/perl -w
use strict;
use Tk;
use Tk::Pane;

my $mw = MainWindow->new( -title => "SACL Survey" );
my $pane = $mw->Scrolled(qw/Pane -scrollbars osow/)->pack(
  -expand => 'yes',
  -fill   => 'both',
);
my $frame = $pane->Frame->pack();

$mw->Label( -text => "... <insert directions here> ..." )->pack();

my @button_values;
my @frame_widgets;

sub button_set {
  my $i = int(shift);
  my $prev = $i - 1;
  my $next = $i + 1;
  my $first =  1;
  my $last  = 30;
  $prev = $first if $prev < $first;
  $next = $last  if $next > $last;

  $_->destroy foreach reverse @frame_widgets;
  @frame_widgets = ();

  push @frame_widgets, $frame->Label(
    -text => "Survey Question #$i",
  )->pack();

  push @frame_widgets, $frame->Button(
    -text    => "First",
    -command => sub { button_set($first) },
  )->pack(
    -side=>'left',
  );

  push @frame_widgets, $frame->Button(
    -text    => "Back to $prev",
    -command => sub { button_set($prev) },
  )->pack(
    -side=>'left',
  );

  foreach my $j (1..4) {
    push @frame_widgets, $frame->Radiobutton(
      -text     => $j,
      -value    => $j,
      -variable => \$button_values[$i-1],
    )->pack(
      -side   => 'left',
    );
  }

  push @frame_widgets, $frame->Button(
    -text    => "Forward to $next",
    -command => sub { button_set($next) },
  )->pack(
    -side => 'left',
  );

  push @frame_widgets, $frame->Button(
    -text    => "Last",
    -command => sub { button_set($last) },
  )->pack(
    -side => 'left',
  );

}

button_set(1);

MainLoop;

use Data::Dumper;
print Dumper \@button_values;