# Problem with dynamic selects **URL:** \ **Category:** Rails\ **Created:** [May 1, 2009, 11:19am UTC](https://www.ruby-forum.com/t/problem-with-dynamic-selects/166955 "2009-05-01T11:19:10Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![bradherman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/bbce88/32.png) [@bradherman](https://www.ruby-forum.com/u/bradherman)\ **Post date:** [May 1, 2009, 11:19am UTC](https://www.ruby-forum.com/t/problem-with-dynamic-selects/166955/1 "2009-05-01T11:19:10Z")
I’m trying to create dynamic select menus for my application. I have a partial that is rendered by an action in my site controller after an :onchange event is triggered. I’ll post the three pieces of code and the error I keep getting. _\_models.html.haml_ - if models = collection\_select :model\_id, models, :id, :name, {:prompt =\> “Select Model”} _site\_controller.rb_ def update\_models # update models in dynamic select boxes make = Make.find(params[:make\_id]) models = make.models render :update do |page| page.replace\_html ‘models’, :partial =\> ‘models’, :object =\> models end end _browse.html.haml_ .form\_row = form.collection\_select :make\_id, Make.find(:all), :id, :name, {:prompt =\> “Select Makes”}, {:onchange =\> “#{remote\_function(:url =\> {:action =\> “update\_models”}, :with =\> “‘make\_id=’+value”)}”} .form\_row#models = render :partial =\> ‘models’, :object =\> @models And from my log: Processing SiteController#update\_models (for 127.0.0.1 at 2009-05-01 04:41:13) [POST] Parameters: {“authenticity\_token”=\>“aOem8MBQboKI/e+KdHjNKgm2DvIQYFCyk14o6TtCj/w=”, “make\_id”=\>“1”} Asked for a remote server ? true, ENV[“FERRET\_USE\_LOCAL\_INDEX”] is nil, looks like we are not the server Will use local index. using index in C:/Users/Bradley/Documents/Aptana Studio/GreenYard\_003/index/development/make default field list: [:name] e[4;35;1mMake Columns (13.0ms)e[0m e[0mSHOW FIELDS FROM `makes`e[0m e[4;36;1mMake Load (1.0ms)e[0m e[0;1mSELECT \* FROM `makes` WHERE (`makes`.`id` = 1) e[0m Asked for a remote server ? true, ENV[“FERRET\_USE\_LOCAL\_INDEX”] is nil, looks like we are not the server Will use local index. using index in C:/Users/Bradley/Documents/Aptana Studio/GreenYard\_003/index/development/model default field list: [:name] ActionView::TemplateError (undefined method `map’ for 🆔Symbol) on line #2 of app/views/site/\_models.html.haml: 1: - if @models 2: = collection\_select :model\_id, @models.name, :id, :name, {:prompt =\> “Select Model”} ``` app/views/site/_models.html.haml:2:in ``` `_run_haml_app47views47site47_models46html46haml_locals_models_object' haml (2.0.9) lib/haml/helpers/action_view_mods.rb:14:in`render’ app/controllers/site\_controller.rb:46:in `__instance_exec0' app/controllers/site_controller.rb:45:in`update\_models’ haml (2.0.9) lib/sass/plugin/rails.rb:19:in `process' c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:104:in`service’ c:/ruby/lib/ruby/1.8/webrick/httpserver.rb:65:in `run' c:/ruby/lib/ruby/1.8/webrick/server.rb:173:in`start\_thread’ c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in `start' c:/ruby/lib/ruby/1.8/webrick/server.rb:162:in`start\_thread’ c:/ruby/lib/ruby/1.8/webrick/server.rb:95:in `start' c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in`each’ c:/ruby/lib/ruby/1.8/webrick/server.rb:92:in `start' c:/ruby/lib/ruby/1.8/webrick/server.rb:23:in`start’ c:/ruby/lib/ruby/1.8/webrick/server.rb:82:in `start' -e:2:in`load’ -e:2 Rendered rescues/\_trace (193.0ms) Rendered rescues/\_request\_and\_response (1.0ms) Rendering rescues/layout (internal\_server\_error) es/\_request\_and\_response (1.0ms) Rendering rescues/layout (internal\_server\_error) e[4;35;1mSQL (1.0ms)e[0m e[0mSET NAMES 'utf8’e[0m e[4;36;1mSQL (0.0ms)e[0m e[0;1mSET SQL\_AUTO\_IS\_NULL=0e[0m Any suggestions? Thanks! ---
**Author:** ![bradherman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/bbce88/32.png) [@bradherman](https://www.ruby-forum.com/u/bradherman)\ **Post date:** [May 1, 2009, 12:14pm UTC](https://www.ruby-forum.com/t/problem-with-dynamic-selects/166955/2 "2009-05-01T12:14:24Z")
Hi, can you verify parameters to collection\_select. Are they proper? Regards, gaurav On May 1, 2:19 pm, Bradley H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ---
**Author:** ![bradherman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/bbce88/32.png) [@bradherman](https://www.ruby-forum.com/u/bradherman)\ **Post date:** [May 1, 2009, 10:51pm UTC](https://www.ruby-forum.com/t/problem-with-dynamic-selects/166955/3 "2009-05-01T22:51:34Z")
Okay I solved that, partially. I needed to pass :locals =\> {:form =\> form} from my view when first rendering the partial. The problem is, though, that on the :onchange event, the partial is rendered through the controller, so I can’t pass :locals from there. So after the :onchange event, I get the same error with the form.collection\_select throwing a “Wrong number of arguments 0 for 1” error. ---
**Author:** ![bradherman](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/bbce88/32.png) [@bradherman](https://www.ruby-forum.com/u/bradherman)\ **Post date:** [May 1, 2009, 10:09pm UTC](https://www.ruby-forum.com/t/problem-with-dynamic-selects/166955/4 "2009-05-01T22:09:28Z")
gaurav v bagga wrote: > Hi, > can you verify parameters to collection\_select. Are they proper? > > Regards, > gaurav > > On May 1, 2:19�pm, Bradley H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) After doing some testing, it would appear Rails is just having a major problem with my partial. The parameters are fine, but something about having that code in a partial is throwing it off. When I replace the current stuff with the exact same code that I have in my browse.html.haml layout, it messes up and gives me weird errors about arguments… wrong number of arguments (0 for 1) Extracted source (around line #4): 1: - if @models 2: = form.collection\_select :model\_id, @models, :id, :name, :prompt =\> “Select Model” 3: - else 4: = form.collection\_select :model\_id, Model.find(:all), :id, :name, {:prompt =\> “Select Model”} If I leave “form.” off, I get the “undefined method :map for 🆔Symbol error” still.