Simple Form Association with Text Field - ruby-on-rails-3

Question

I have a Rails app that is using the simple_form gem. I have two models that are related, trades and stocks. In the form for trades, I want users to be able to enter their stock ticker symbol in a text field. Currently, I'm using the association function which renders a select box. The problem is that I want a text field instead since I have about a thousand stocks to choose from.
Is there a way I can do this (with or without Simple Form)?
the models:
class Trade < ActiveRecord::Base
belongs_to :stock
end
class Stock < ActiveRecord::Base
has_many :trades
end
the form on trades#new
<%= simple_form_for(#trade) do |f| %>
<%= f.association :stock %>
<% end %>

Answer 1

You should be able to just use this syntax:
<%= f.input :stock_id, :label => 'Enter your ticker:' %>
The problem here is that the user will not know what :stock_id is, as it's a reference to one of your many Stock objects.
So you probably want to implement a simple jquery autocomplete interface that returns a list of stocks like so:
[{:ticker => 'AAPL', :name => 'Apple Inc', :id => 1}, {:ticker => 'IBM', :name => 'International Business Machines', :id => 2}, etc ]
You can then display something like this as autocomplete results:
AAPL - Apple Inc
IBM - International Business Machines
and allow the user to select the one they are looking for. Behind the scenes you capture the :id and use that as your associated :stock_id.
You will need to add a stocks_controller action that takes a string and looks up Stocks based on a partial ticker and returns a max-number of stocks like 20.
def search
ticker_query = "%#{params[:ticker]}%"
stocks = Stock.where('ticker LIKE ?', ticker_query).limit(20)
render :json => stocks
end