Question

GIST is here:
https://gist.github.com/1553371

These are the models I have:

class Character < ActiveRecord::Base
  has_many :weapons
end

class Weapon < ActiveRecord::Base
  belongs_to :character
end

and this is what my view in HAML looks like:

= form_for(@weapon) do |f|
  %ul.fields
    %li
      = f.label :character
      = collection_select :weapon, :character_id, Character.all, :id, :name, {:prompt => 'Please Select a Character.'}

but I keep getting this error:

undefined method `character_id' for #<Weapon:0x007f9033232088>

I’ve attempted using a string for character_id, that also didn’t work. The form renders with :character, but then of course it won’t save back since it needs the id.

Answer 1

Your code looks fine, it’s likely that you don’t have a character_id field on your weapon model. If you do then you have pending migrations that need to be run.

You can check the current state of your database by looking at db/schema.db it will show if you have the character_id column or not.

You can run your migrations using rake db:migrate then use rake db:test:prepare to update your test database as well.

If it’s not working after running migrations then you’ll need to create one, should look something like:

# db/migrations/add_character_id_to_weapons.rb
class AddCharacterIdToWeapons < ActiveRecord::Migration
  def change
    add_column :weapons, :character_id, :integer
  end
end