To have your Pane fill the panel, it is best to use pack at the main window level: 
#!/usr/bin/perl

use Tk;
use Tk::Pane;

my $mw = MainWindow->new( -title => "SACL Survey" );
my $pane = $mw->Scrolled(qw/Pane -scrollbars osw/
                        )->pack(-fill => "both", -expand => 1);

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

for (1..30) {
  $pane->Radiobutton(
    -text => "button 1",
    -value => "1",
    -justify => "left",
    -variable => \${"rb1_q$_"},
  )->grid(
    $pane->Radiobutton(
      -text => "button 2",
      -value => "2",
      -justify => "left",
      -variable => \${"rb2_q$_"},
    ),
    $pane->Radiobutton(
      -text => "button 3",
      -value => "3",
      -justify => "left",
      -variable => \${"rb3_q$_"},
    ),
    $pane->Radiobutton(
      -text => "button 4",
      -value => "4",
      -justify => "left",
      -variable => \${"rb4_q$_"},
    ));
}

MainLoop;

[download]
Note that the button sizes will not expand to fill the window; the grid method creates a fixed grid. But the pane, which uses pack, will adjust scroll bars according to window size, even disappearing when not needed.

-Mark

In reply to Re: Some beginning Tk help by kvale
in thread Some beginning Tk help by dimmesdale

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