Re: Trying to add widgets via callback

[Owen Taylor <owt1 cornell edu>]

Toshio Kuratomi <badger@prtr-13.ucsc.edu> writes:

> > vbox already is a pointer to your container, and the contents of
> > &vbox will be lost after newWindow is left because the it is a stack
> > variable.
> > 
> Okay.  That makes sense.  But the three changes don't make my problem
> disappear.  I still get the same error in the same place.
> 
> Since vbox is a pointer to a container, will vbox disappear as well?  Do I
> need to send a dereferenced vbox to my callback?  How do I manage that?
> (gtk_signal_connect seems to expect a pointer as its fourth element).

No, the vbox won't disappear until the window that it is added
to is destroyed. (The subject is a bit more complex, but those
complexities (reference-counting) can be ignored for the moment). 

  *vbox  is the structure in memory
   vbox  is the address of the structure in memory
  &vbox  is the address of the variable which holds the address
         of the structure in memory.

If that seems confusing, I would suggest taking a look at a good
book on C. (Kernigan + Ritchie, 2nd ed is a traditional choice.)
[ No offense intended if this seems like easy stuff - I may 
  have misunderstood your question ]

You want to pass vbox to gtk_signal_connect.

With Tim's changes, it should work. If you are still having problems,
you might want to try posting the complete code of a minimal
example program that shows the behavior. (It's a little hard
to guess what you've omitted to save space, and what you
might be missing)

Regards,
                                        Owen