[html-formfu] re: Confusion with options_from_model and many_to_many

[Toby Corkindale]

Hi,
I've just joined the list, but wondered if anyone, including Leanan, 
resolved the issue in their email from March:
http://lists.scsys.co.uk/pipermail/html-formfu/2009-March/001852.html

I just ask because I seem to be having the identical problem..
I have a classic many-to-many relationship, but can't get this to work 
as per the documentation.

Example:

table books (id, title)
.. ->has_many(book_genres => 'BookGenres', 'book')
.. ->man_to_many(genres => 'book_genres', 'genre')

table genres (id, name)
.. ->has_many(book_genres => 'BookGenres', 'genre')
.. ->many_to_many(books => 'book_genres', 'book')

table book_genres (book, genre);
.. ->belongs_to(book => books)
.. ->belongs_to(genre => genres)

So the formfu definition for a book should be:

elements:
  - name: title
    type: Text
  - type: Checkboxgroup
    name: genres


However in practice that doesn't work.. After some experimentation, I 
ended up with the following:

elements:
  - name: title
    type: Text
  - type: Checkboxgroup
    name: genres
    model_config:
      default_column: 'me.id'
      resultset: Genres

This at least renders the form, and populates the options that are 
available. However the current options are not pre-set, nor are changes 
saved to the database.

I'm probably doing something wrong, but wondered if you could help me 
figure out what! I've been banging my head against this for ages.

Thanks,
Toby