Hello Loops,

      Thanks a lot for your swift response and insight. I also read through another response from AM. Just to make sure I understand this correctly,

1. A parent/child hierarchy is established at the creation phase of objects. For ex:
   

   my $t_button = $mw->Button(-text=>'OK',
                              -command=>sub{exit});
   [download]

   This makes the object pointed to by $t_button a child of the object pointed to by $mw.


2. A master/slave hierarchy is established by the geometry manager used(such as grid, pack, form, place).


3. When displaying a widget, if the -in option is not at all used then the master/slave hierarchy is exactly the same as parent/child hierarchy.

If this understanding of mine is correct, then I proceed to a portion of your next statement:

• ....trying to repack a button with first tab parent into a second tab, changes the geometry...

This, I believe, you meant that the pack geometry manager attempts to pack first tab inside the second tab of the same NoteBook. This of-course is not permitted, after all every tab of any given NoteBook must NOT ONLY be a direct child BUT ALSO a direct slave under that NoteBook

• ...but not the parent/child relationship -- meaning the stacking wouldn't work.
  This I didn't understand, honestly. So please let me know.

Moving on...Yes, after you said that making button a child of main window, I tried it and it works. But if I change the button to be a child of NoteBook i.e.

my $t_button = $nb->Button(-text=>'OK',
                           -command=>sub{exit});
[download]

Then not only does the button not show up, I don't get any error from the execution of pack statement inside the callbacks either when the callbacks are executed. What's going on ? Can you please tell me what's the problem here?

Hey, Thank you for your patience in reading my query.