I have a treeview that is populated from a treemodel.
I would like to add a colum to the treeview.  Is it possible to draw the data for that column from a separate treemodel or can I append at runtime a column to the existing treemodel?
To answer the question in the title:  No, you can't add columns to a GtkTreeModel after it's been created.
Can I add a column to an existing treemodel in gtk?