[gtkmm] Treeview help needed

[David Kinyanjui <david i2software com>]

Hello everyone;
I have implemented a treeview with three columns.
First column stores orderid, second column store order name and third 
column stores the order date.
My intent is to be able to reorder the entries by any column of choice 
(at UI level) ...  by clicking the the column header.
For instance, if the user click the date column the entries will be 
reordered by that column (either ascendingly or desc.) automagically and 
so on, and so forth.
If this is possible to attain,... please, can anyone out there give help.
your ideas, hints and/ or examples will be highly appreciated
Sincerely,
David