Problems with collection_selects

[maep]

Hello friends!
I am trying to make city select on my page. So, I have countries, that
has_many cities. account belongs_to city.

I have found example here:
http://pullmonkey.com/2008/3/30/dynamic-select-boxes-ruby-on-rails

So, this way I am doing that. But I have one problem, and two questions

Problem: when user submits form (press Update button), I need do assign
@account.city_id to chosen city_id. I can’t get value of parametr! (Even
country_id seems to be nil in update method)

Questions:

1. How to get this lovely parametrs in update method?

2. How to use form_for.collection_select helper? I am using form_for,
   and it’s rather strange not to use collection_select from it, but it
   does not work!
   And, finally - how to make collection_Select result be avaliable in
   account parmetrs, to use just @account.update_attributes (without
   rewriting update method)

Thank you in advance,
here is the code:

account controller:

1. class AccountsController < ApplicationController
   2. …
   3. # GET /accounts/1/edit
   4. def edit
   5. @account = Account.find(params[:id])
   6. @countries = Country.find(:all)
   7. @cities = City.find(:all)
   8. end
   9. def update

2. @account = Account.find(params[:id])
   

3. mama = params[:city_id] # here it is null.
   

4. respond_to do |format|
   

5.   if @account.update_attributes(params[:account])
   

6.     flash[:notice] = 'Account was successfully updated.'
   

7.     format.html { redirect_to(@account) }
   

8.     format.xml  { head :ok }
   

9.   else
   

10.     format.html { render :action => "edit" }
    

11.     format.xml  { render :xml => @account.errors, :status =>
    

:unprocessable_entity }
20. end
21. end
22. end
23. def update_cities
24. puts "mama papa " + params[:country_id].to_s
25. country = Country.find(params[:country_id])
26. cities = country.cities
27.
28. render :update do |page|
29. page.replace_html ‘cities’, :partial => ‘cities’, :object =>
cities
30. end
31.
32. end
33. end

edit view:

1. Editing account

3. <%= error_messages_for :account %>
5. <% form_for(@account) do |f| %>

7. <b>Name1</b><br />
   

8. <%= f.text_field :name1 %>
   

12. <b>Country</b><br />
    

13. <%= collection_select(nil, :country_id, @countries, :id,
    

:name,{},
14. {:onchange => “#{remote_function(:url => {:action =>
“update_cities”},
15. :with =>
“‘country_id=’+value”)}”}) %>
16.

17.
18.

<%= render :partial => “cities”, :object =>
@cities %>

19.
20.

21. Avatar

22. <%= f.text_field :avatar %>
23.

24.
25.

26. <%= f.submit “Update” %>
27.

28. <% end %>

partial _city:

2. <b>City</b><br />
   

3. <%= collection_select(nil, :city_id, cities, :id, :name) %>