search for: habtm_helper_plugin

I''m trying to get one of those 2-column select lists (where there''s an "Add>>" and a "<<Remove" button between them) working for a Rails application. First of all, what the heck is this thing called? You''d list all of the available items in one select list, and the selected ones in the other. Items move from one list to the other, but

Is there a standard practice for providing a UI into HBTM relationships? I have a model User, and a model Training, and I need to manage both relationships -- show me all the people that have training X, but also show me all trainings user U has. And, of course, "Lookup this user and then add/remove trainings for this person" or "Lookup this training and add/remove