Java The Hutt

I didn't expect my next post to be so quick but this cropped up tonight while I was working on my app.
This is just a quick post for anyone else that may need to use a date_select more than once on a page. Here's some code:

< %=date_select(:borrower_profile, :date_of_birth,   :order => [:month, :day, :year], :start_year => Time.new.years_ago(7).to_date.year, 
    :end_year => Time.new.years_ago(104).to_date.year, :include_blank => true, :index => index)% >

In the above snippet creates a set of select widgets to obtain a birthdate with rails' date_select helper method. The problem is that I'm using this helper to obtain birthdates for many users which means I need some sort of index value to track which birthday is attached to which user.

So basically I need HTML like the following to appear in my page:

< select name="borrower_profile[2][date_of_birth(2i)]" > <-- month
< select name="borrower_profile[2][date_of_birth(3i)]" > <-- day
< select name="borrower_profile[2][date_of_birth(1i)]" > <-- year

The :index => index part of my tag in the first code snippet is what is supposed to provide the index value in my select name value "borrower_profile[2]" (2 is the index value).

As it is rails 1.0 and earlier will always ignore :index and generate: "borrower_profile[date_of_birth(2i)]", etc

As it turns out the date_helper method doesn't recognize the :index parameter which many, if not all, other form helper methods do recognize (text_field, select, radio_button, etc). This is most likely just an oversight. At any rate I can't wait for this to be fixed as I need this right now so I dug into rails and fixed it myself.

With some help on IRC I figured out the easiest way to create a patch for rails and have it as part of my app until I can submit it or file a bug to have it fixed in a future release. Anyway, the fix is as follows (This assumes you want to apply the patch from your app and not your rails installation. If not then you can just make the changes outlined below in your rails installation):

1) Paste the following code into a file called date_helper.rb and place it into your application's lib directory.

require "date"

module ActionView
  module Helpers
    class InstanceTag #:nodoc:
      include DateHelper
      
      alias :__to_date_select_tag :to_date_select_tag
      
      def to_date_select_tag(options = {})
        defaults = { :discard_type => true }
        options  = defaults.merge(options)

        # begin patch
        if options[:index]
          @index = options[:index]
          options_with_prefix = Proc.new { |position| options.merge(:prefix => "#{@object_name}[#{@index}][#{@method_name}(#{position}i)]") }
        else
          options_with_prefix = Proc.new { |position| options.merge(:prefix => "#{@object_name}[#{@method_name}(#{position}i)]") }
        end
        # end patch

        date     = options[:include_blank] ? (value || 0) : (value || Date.today)

        date_select = ''
        options[:order]   = [:month, :year, :day] if options[:month_before_year] # For backwards compatibility
        options[:order] ||= [:year, :month, :day]

        position = {:year => 1, :month => 2, :day => 3}

        discard = {}
        discard[:year]  = true if options[:discard_year]
        discard[:month] = true if options[:discard_month]
        discard[:day]   = true if options[:discard_day] or options[:discard_month]

        options[:order].each do |param|
          date_select << self.send("select_#{param}", date, options_with_prefix.call(position[param])) unless discard[param]
        end

        date_select
      end
    end
  end
end

2) Place a require 'date_helper' in your environment.rb file
3) restart your webserver
4) use the date_select helper function with the :index option and you'll see your field indexed properly. yay!

Enjoy!