Re: [gtkmm] Custom TreeStore Problems

[darco <darco deepdarc com>]

Woo-hoo! After examining your code, I found out what I was missing -- 
apparently I was doing the whole Glib::Object initialization wrong. 
Thanks a bunch, your example helped a lot!

I corrected my customtrreestore.tar.gz example, and it is now online if 
anyone wants to look at it.

On Monday, April 28, 2003, at 08:45  PM, Thomas Muldowney wrote:
> I'd be more than happy to answer questions about what I did, or receive
> any feedback about more correct ways to do things.  Especially related
> to the RosterModel_Class (Glib::Class).

I noticed in your code that you set the iterator stamp to a constant 
value (42). While I'm not quite sure how the stamp of the iterator is 
suppose to be handled, I handled it by having a different stamp value 
per model instance. The stamp value is stored in the model, and is 
calculated at construction. Perhaps one could also recalculate that 
stamp when iterators become invalid...? In my example I check the 
validity of iterators in all of the virtual functions, although I'm not 
sure if that's what I am suppose to do. (I calculated the stamp to be a 
unix timestamp + the address of the TreeModel instance.)

Then again, that topic is probably more suitable for a different 
mailing list.

--- darco
http://www.deepdarc.com/

PS: Here is the full message that Thomas sent me, as it seems as though 
it didn't quite make it to the mailing list:

On Monday, April 28, 2003, at 08:45  PM, Thomas Muldowney wrote:

> I've recently battled through this myself and have defeated it!  That's
> to say I got something working.  I'm not sure if it's 100% correct, but
> it seems to be working great.  The code is available in the Gabber2 
> CVS,
> you can use viewcvs.cgi here:
>
> http://www.jabberstudio.org/cgi-bin/viewcvs.cgi/gabber/src/
>
> RosterModel.cc and .hh have the actual model implementation, and it's
> used as the model for the treeview contained in RosterView.
>
> I'd be more than happy to answer questions about what I did, or receive
> any feedback about more correct ways to do things.  Especially related
> to the RosterModel_Class (Glib::Class).  I'd also be willing to write 
> up
> a small tutorial with more simple code and implementation if the code
> I've written is deemed mostly correct =)
>
> --temas
>
>
> On Mon, 2003-04-28 at 20:45, darco wrote:
> > I am trying to implement a Custom TreeStore using GtkMM. Unable to
> > find any documentation on how to do this, I figured I would just give
> > it a shot and see if I could figure it out. But I have now come to a
> > point where I am stumped. I'm not sure if I'm just missing something,
> > or if it is a bug.
> >
> >
> > Seeing as there is no example for creating a custom tree store in the
> > GtkMM tarball, I wrote a small program that (if it worked) would
> > demonstrate how to do this. After if is fixed and working, it might be
> > helpful if it were included into the tarball (or perhaps elsewhere)
> > for others to examine.
> >
> >
> > Right now, I'm getting the following runtime errors:
> >
> >
> > <fixed><fontfamily><param>Courier 
> > New</param><bigger>(customtreestore:343):
> > glibmm-CRITICAL **: file interface.cc: line 53
> > (Glib::Interface::Interface(const Glib::Interface_Class&)): assertion
> > `gobject_ != 0' failed
> >
> >
> > (customtreestore:343): glibmm-CRITICAL **: file interface.cc: line 53
> > (Glib::Interface::Interface(const Glib::Interface_Class&)): assertion
> > `gobject_ != 0' failed
> >
> >
> > (customtreestore:343): glibmm-CRITICAL **: file interface.cc: line 53
> > (Glib::Interface::Interface(const Glib::Interface_Class&)): assertion
> > `gobject_ != 0' failed
> >
> >
> > (customtreestore:343): glibmm-CRITICAL **: file interface.cc: line 53
> > (Glib::Interface::Interface(const Glib::Interface_Class&)): assertion
> > `gobject_ != 0' failed
> >
> >
> > (customtreestore:343): GLib-GObject-CRITICAL **: file gobject.c: line
> > 1319 (g_object_ref): assertion `G_IS_OBJECT (object)' failed
> >
> >
> > (customtreestore:343): GLib-GObject-CRITICAL **: file gobject.c: line
> > 1337 (g_object_unref): assertion `G_IS_OBJECT (object)' failed
> >
> >
> > (customtreestore:343): GLib-GObject-CRITICAL **: file gobject.c: line
> > 1337 (g_object_unref): assertion `G_IS_OBJECT (object)' failed
> >
> > </bigger></fontfamily></fixed>
> >
> > Oddly enough, several of these errors appear when I am copying the
> > Glib::RefPtr<<> for the CustomTreeStore! I find this to be most
> > bizzare. NONE of the virtual functions are being called, and I don't
> > know why. Is it possible that I'm not using the Glib::RefPtr<<>
> > correctly?
> >
> >
> > I saw that someone earlier mentioned having similar problems and
> > Murray suggested the following:
> >
> > <excerpt>I suspect that a custom Store might require similar
> > techniques as a custom CellRenderer, because it might require the
> > definition of a new GObject type at runtime. You should probably look
> > at the constructors in the custom cellrenderer example.
> >
> > </excerpt>
> >
> > I just wanted to say that I am doing this, and the program still
> > yields the results shown above.
> >
> >
> > The source code to this example can be found here:
> >
> > ftp://ftp.voria.net/pub/customtreestore.tar.gz (Or if you prefer http,
> > use http://ftp.voria.net/pub/customtreestore.tar.gz )
> >
> >
> > Thanks in advance!
> >
> >
> > --- darco
> >
> > http://www.deepdarc.com/