Tk gurus:

I want to have a text widget where I can display a running log from a process. Example code below. This all works fine except if the x-axis scroll bar is at it's maximum right hand position relative to the text widget and more text is printed to the widget the x-axis scrollbar moves to it's most left hand position. I want the scrollbar to stay at it's current postion.

This is my first attempt at using Tk.... I can't figure out how to control this - or if's it's controllable. Maybe there is a better method. All suggestions are most welome.

Thanks! 

use strict;
use Tk;

my ($mainwindow, $menubar, $display, $text);

my $counter = 0;

$mainwindow = new MainWindow;
$mainwindow->geometry("800x400");

$display = $mainwindow->Scrolled('Text', -relief=>'sunken',
-borderwidth=>'2',
  -height=>'24', -scrollbars=>'se', '-width' => 40, '-wrap'=>'none');
$display->pack(-expand=>'1', -fill=>'both');

$text =  $display->Subwidget('text');           # need this because yo
+u
can't tie to $display - main widget
tie *STDOUT, ref $text, $text;

create_gui_main();

$text->repeat(
  1000, sub {
    goto \&mymain;
  },
);

MainLoop;

sub mymain() {
  # This would normally be real text
  $counter++;
  print "this is a very long line we need a scrollbar on the x
axis........ this is a very long line we need a scrollbar on the x
axis........ this is a very long line we need a scrollbar on the x
axis........ well the number is current = " . $counter . " \n";
}

# ------------------------ #
sub quitapp() {
  exit;
}

# ------------------------ #
sub create_gui_main {
  my $menuitems = [
    [Cascade => "~File", -menuitems => [
        [Button => "~Quit", -command => \&quitapp],
      ]
    ],
  ];
  if ($Tk::VERSION >= 800) {
    $menubar = $mainwindow->Menu(-menuitems => $menuitems);
      $mainwindow->configure(-menu => $menubar);
  } else {
    $mainwindow->Menubutton(-text => "Pseudo menubar",
      -menuitems => $menuitems)->pack;
  }
}
__END__

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In reply to Tk and scrollbars by Anonymous Monk

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