how to get value selected by using select_tag with options_from_collection_for_select and pass it to controller

Question

I have built a form search like this:

<%= form_tag({ controller: 'questions', action: 'search_topic' }, method: 'get') do %>
  <%= select_tag 'search_topic', options_from_collection_for_select(current_user.get_topics, :id, :name) %>
  <%= submit_tag "Search", name: nil, class: 'btn' %>
<% end %>

I want to search all questions of a topic selected from select box, i used sunspot to help for search, so now how can i pass value select from select box to controller for search, i used below code to pass a params[:search]:

<%= select_tag 'search_topic', options_from_collection_for_select(current_user.get_topics, :id, :name), params[:search] %>

but it has error:

undefined method `[]' for nil:NilClass

this is my controller:

def search_topic
  @search = Question.search do
    with(:topic_id, params[:search])
    paginate page: 1, per_page: 10
  end

  @questions = @search.results
  render 'index'
end

so, how can i pass value selected from select box on form to controller for search?

score 4 · Answer 1 · answered Nov 02 '12 at 18:59

<%= select_tag 'search_topic', 
  options_from_collection_for_select(current_user.get_topics, :id, :name) %>

This assumes the view code shown is inside a form. If that form posts, it ends up say in the create action with:

params[:search_topic]

containing the value you selected.

score 3 · Accepted Answer · answered Nov 02 '12 at 18:56

3

Hey there is no need to pass params[:search].
Rails automatically generates params for select when submit button would be clicked.

If you want to params name to be 'search', then change the name of select 'search-topic' to 'search'.

If you want to check value of params, that how would it recieve in params, try debugger and check value of params generated by this form.

Also, there is a shortcut, try to put an error in the action to be called after pressing submit, and read params on the browser page. Also you can print in flash on next page

answered Nov 02 '12 at 18:56

Akshay Vishnoi

1,252
12
15

i have passed it in controller, but something wrong with search. – Thanh Nov 02 '12 at 19:15
what did you do in controller? can you just share your code in controller and view file, and also error if possible – Akshay Vishnoi Nov 02 '12 at 19:18
my controller and view are in my questions, only different is i have changed params[:search] to params[:search_topic]. – Thanh Nov 02 '12 at 19:20
some topics don't return any questions althrough those topics have questions, some topics have questions returned but i can't paginate to move next page. I use `will_paginate`. – Thanh Nov 02 '12 at 19:26
the problem is i can't paginate to move next page. – Thanh Nov 02 '12 at 19:32
2

TRY USING paginate page: params[:page], per_page: 10 – Akshay Vishnoi Nov 02 '12 at 19:40

how to get value selected by using select_tag with options_from_collection_for_select and pass it to controller

2 Answers2