Hi,

I'm trying to create a simple two-stage GUI using Tk. The first box is for fetching a user selection. When the selection is made, I destroy the first box and create a second. I'm getting segfaults when processing input on the second box.

This is my first attempt at Tk so perhaps the approach is simply wrong or there's a better way. Any suggestions?

Thanks, Stefan 

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

my $MW;
my $Array_Index="";

MAIN:
{
  debug("+MAIN");
  my $my_ref;
  my $label ;
  my @file_references ;
  my $button ;
  my $i;

  $MW = MainWindow->new;
  $MW->title("test box 1");
  $label = $MW -> Label(-text=>"Choose one option",
            -font=>"courierfont") -> pack;

  @file_references = ("Ref1", "Ref2", "Ref3", "Ref4");
  $i=1;

  foreach $my_ref (@file_references)
  {
    $button = $MW -> Button(-text => "$my_ref",
      -command => [ \&do_button, "$my_ref,$i"])-> pack;
    $i++;
  }

  MainLoop();
  debug("==MAIN - the first box has been closed");

  if (length("$Array_Index") > 0)
  {
    $MW=MainWindow->new;
    $MW->OnDestroy([\&abort_routine]);
    $MW->title("test box 2");
    $label = $MW -> Label(-text=>"This is the second box") -> pack;
    $label = $MW -> Label(-text=>"Index = $Array_Index",
              -font=>"courierfont") -> pack;
    $button = $MW -> Button(-text => "Shutdown and close",
    -command => [ \&abort_routine])-> pack(-side => 'bottom');

    MainLoop();
  }

  debug ("-MAIN");
}

sub do_button
{
  debug("+do_button");
  my $params = shift;
  (my $ref, $Array_Index) = split (/,/,$params);
  debug("do_button Array_Index: $Array_Index");

  # DO SOMETHING USEFUL HERE TO START A PROCESS

  $MW->destroy();
  debug("-do_button");
}

sub abort_routine
{
  debug("+abort_routine");
  debug("abort_routine Array_Index: $Array_Index");

  # DO SOMETHING USEFUL HERE TO CLEAN UP THE PROCESS

  $MW->destroy();
  debug("-abort_routine");
}

sub debug
{
  my @msg = shift;
  print @msg, "\n";
}

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In reply to Getting segfaults when destroying and recreating Tk box by skt

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