Ruby on Rails - Multiparameter assignment and attr_accessor and 12_hour_time

Question

Ok, I'm slowly getting a grasp on this, but I need some more help.

I'm using a time_select in my view, therefore I'm dealing with a multiparameter assignment. Check.

<%= pt.time_select :time, :twelve_hour => true, :minute_step => 5 %>

BUT I'm doing the naughty thing and using it with an attribute that isn't in the database:

attr_accessor time

Therefore since it can't look at the db, it can't piece together what the multiparameter assignment is supposed to be and therefore I get the following error:

1 error(s) on assignment of multiparameter attributes

Thus I am using information I found here:

  composed_of :time,
            :class_name => 'DateTime',
            :mapping => [%w(DateTime to_s)],
            :constructor => Proc.new{ |item| item },
            :converter => Proc.new{ |item| item }

Other helpful links: rubyonrails.org | apidock.com

This remove the error, but now the issue is that the plugin I'm using doesn't function properly, I think. I am using http://code.google.com/p/rails-twelve-hour-time-plugin/. The goal being, I'm trying to get the time select to have 3 drop downs: hh:mm am/pm.

So the question is: how do I need to adjust my composed_of method in order for it to be properly converted by the plugin? OR is there a better method to this madness?

I'm not sure what mappers / constructors / converters I need. Right now the object keeps the hour and minute, except the hour isn't converted to 24 hour (which the plugin is supposed to take care of, I thought).

Answer 1

The issue was that I didn't follow the article properly. I should have been using the Time model.

  composed_of :time,
            :class_name => 'Time',
            :mapping => [%w(Time to_s)],
            :constructor => Proc.new{ |item| item },
            :converter => Proc.new{ |item| item }

Looks like this is a common problem. For more information about it check out this link. The suggestion given there is to do:

class Whatever < ActiveRecord::Base
  ...

  attr_accessor :arrival_time
  columns_hash["arrival_time"] = ActiveRecord::ConnectionAdapters::Column.new("arrival_time", nil, "time")
end

I'm still working out bugs, but I'll update this when I get something working.