Re: GtkTreeModelMapping

[Owen Taylor <otaylor redhat com>]

Alexander Larsson <alla lysator liu se> writes:

> I was gonna put some abstract types in a GtkTreeView to view them, only
> i didn't want to copy strings from it and place in a GtkListStore, so I
> wrote a TreeModel that takes another model and generates a new one where
> the columns can be specified as transformations of the data in the
> original model.
> 
> For each column in the model a (src_column, col_type, map_func, user_data)
> tupel is used to map the value, where the map_func is of the type:
> 
> typedef void (* GValueMapFunc) (const GValue *a,
> 				GValue *b,
> 				gpointer user_data);
> 
> 
> I think this is of general interest. Comments?

The way that I suggested to Jonathan earlier to do this, and the
way he had half implemented (it's only a few lines of code) is
to avoid the whole column thing at all in this case, and to
able to provide a function for a particular column which 
is passed in, as an argument, the tree row and the renderer,
and is responsible for setting the attributes on the cell
renderer.

So, you have (roughly) something like:

email_name_column_set_attrs (GtkTreeViewColum *column,
                             GtkTreeModel     *model,
                             GtkTreeIter      *iter)
{
  GtkEmailMessage *message;
  GdkColor color;

  gtk_tree_model_get (model, 0, &message, NULL);

  email_message_get_status_color (message, &color);
  g_object_set (column->renderer,
                "foreground_gdk", &color,
                "text",           model->name,
                NULL);
}  
                         

Jonathan's adding the other few lines for that now - take a look
what he commits and see if you like it.

Regards,
                                        Owen