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?
In a gtk.TreeView object there's an append_column method, so yes, you can programmatically add a column to a gtk.TreeView.
However, I'm not aware of any method for adding a new column to an existing model or using multiple models for the same gtk.TreeView. Anyway, I guess you can create a new model with an extra column, copy the contents of the previous one and update the tree view to use the new model.
Can I add a column to an existing treemodel in gtk?