I'm new to rails and was playing with a simple model with
acts_as_threaded. The sql is...

  id integer NOT NULL DEFAULT
  name character varying(100) NOT NULL,
  description text,
  parent_id integer,
  CONSTRAINT bobbits_pkey PRIMARY KEY (id)

and the only change i made after generating scaffolding was of course:

class Bobbit < ActiveRecord::Base
  acts_as_tree :order => "name"

Now I expected that rendering of a bobbit in the browser would present
an drop-down list for parent, but no such luck. Whats up?

could someone at least confirm that I should see a dropdown?

could someone at least confirm that I should see a dropdown?

ah, I see my mistake was skimming the recipe example and I missed the
part where the view was updated with the select/dropdown.

No. acts_as_tree is an extension to ActiveRecord -- the objects-
wrapping-db mechanism in rails (Model). Dropdowns are a function of
the view. By default, the scaffold will generate a text_column for
almost everything but date, datetime, and boolean fields.

If you want a dropdown for parent, you need to change the scaffolded
field that probably looks like:

  <%= text_field f.parent_id %> <----- this one

To something along the lines of....

  <%= select f.parent_id, Bobbit.find(:all, :order=>'name').collect{|
bobbit> [,]} %>

The select object accepts the name of the attribute to be filled
(parent_id), and an enumerable set of options. In the example above,
you're retrieving all the Bobbits, ordered by their name, and creating
an array of name/val pairs to be displayed in the dropdown.