Re: Two warnings when creating a TreeStore

[José Alburquerque <jaalburquerque cox net>]

Murray Cumming wrote:
> On Tue, 2007-09-11 at 17:17 -0400, Paul Davis wrote:
>   
> > On Tue, 2007-09-11 at 17:03 -0400, Jos�lburquerque wrote:
> >
> >     
> > > Any ideas?  Thanks so much.
> > >       
> > What is an "Element" ? Gtkmm can't handle arbitary types as column
> > template args.
> >     
>
> Actually, it can, I think.
>
>   

I did read in the programming guide that it can.

> >  It can handle pointers and all built-in scalar types, as
> > well as std::string and Glib::ustring, plus a few others.
> >     
>
> I think the problem here is indeed that you are using a static instance
> somewhere.
>
>   

Your comments are much appreciated, thank you.  :-)  When you say a 
static instance, are you referring to one of my "Element" derived 
classes or are you referring to the TreeModelColumnRecord class I've 
defined (columns) which *is* static within my "DVDProject" class?  Would 
changing the "staticity" of this static member help?

On another note, can I pick your brain a bit more and ask you a little 
about how gtkmm handles inheritance?  As I had mentioned, all the 
objects I work with are derived from a base class (which I call 
"Element") with a virtual method called "getName()" designed to return a 
string naming the object I'm dealing with (so I can "render" the string 
in the TreeView).  I've overridden the method in various derived 
classes, but in a rendering method (which I set up with the 
TreeView::Column::set_cell_data_func()) when I call the object's 
"getName()" method, it's overridden method is not called, but instead 
the base class method is called.  Am I missing something?  If it helps 
the short TreeView initialization and the rendering method I use 
follows.  I'd really appreciate any insights.  Thanks for your comments.

-Jose

MainWindow::MainWindow() {
   ...
   TreeView::Column* outlineColumn = manage(new TreeView::Column("Outline",
                              DVDProject::columns.element));
  
   CellRenderer* renderer = outlineColumn->get_first_cell_renderer();
   outlineColumn->set_cell_data_func(*renderer,
                         sigc::mem_fun(*this, &MainWindow::renderElement));
  
   outlineTreeView.append_column(*outlineColumn);
   ...
   show_all_children();
}

void MainWindow::renderElement(CellRenderer* renderer,
const TreeModel::iterator& iter) {
   CellRendererText* textRenderer = 
dynamic_cast<CellRendererText*>(renderer);
   const Element& e = (*iter)[DVDProject::columns.element];
   textRenderer->property_text() = e.getName();
}