Question

It would be of great help if some one could help me with an example to implment auto complete feature in my rails application.I tried the jquery auto complete plugin.I was not able to achieve.

My controller:

def new    
@testers = User.find_by_sql("select * from users where id in(select user_id from user_role_assignments where role_id in (select id from roles where name like 'Tester')) order by name").paginate(:page=>params[:page],:per_page=>30)   
respond_to do |format|
  format.html # new.html.erb
  format.xml  { render :xml => @release }
      end
end

I want to create an auto complete for the @testers

view code:

 = form.label :tester_tokens, "Testers" 
 = form.text_field :tester_tokens

Thanks for your help,

Ramya.

Answer 1

Have a look at the Gem rails3-jquery-autocomplete. It should be the base for your implementation. There is even an example application that explains each step you have to take to include it in your application.

At Railscasts.com, you will find an episode that explains how to use it: Autocomplete-association (revised)

If it does not work at all for you, you should come back and ask concrete questions. From your above question, it is not clear where you want to use autocomplete. It is normally used to establish an (additional) association to another object, where you want to replace the drop-down-list or selection-in-list or list of checkboxes by the autocomplete field.

There is an alternative, if you want to have more than one thing selected, have a look at the Railscasts episode “Token Fields”. Because your comment states that this is what you want to do, here are some hints how to do it (copied from my application, you have to replace it by your context, it is a short version of Railscasts 258):

• Install JQuery Tokeninput into your Rails application.
• Ensure that your application knows jquery (by using Gem jquery-rails)
• Include the Javascript file jquery.tokeninput.js into your application (syntax depends on the version you are using).

• Include the following code in your model (User ??):

  class User < ActiveRecord::Base
    attr_accessible :name, :tester_tokens
    has_many :testers
    attr_reader :tester_tokens
  
    def tester_tokens=(ids)
      self.tester_ids = ids.split(",")
    end
  
  end
  

• Include in your application.js the following code:

  $(function () {
    $('#user_tester_tokens').tokenInput('/testers.json', { 
        crossDomain: false,
        prePopulate: $('#user_tester_tokens').data('pre') })
  }); 
  

• Include in your TestersController the following code:

  class TestersController < ApplicationController
    def index
      @testers = Tester.where("name like ?", "%#{params[:q]}%")
      respond_to do |format|
        format.html
        format.json { render :json => @testers.map(&:attributes) }
      end
    end
  end
  

• Change in your view code the following line:

  = form.text_field :tester_tokens, "data-pre" => @user.testers.map(&:attributes).to_json
  

You will find the explanation for all these steps, and some more background at Railscasts episode 258.