Question

I am using Ruby on Rails 3.0.9 and I am trying to implement a “Contact Us” form myself. So…

… in my model file I have:

require 'active_model'

class ContactUs
  include ActiveModel::Conversion
  include ActiveModel::Validations

  attr_accessor :email, :subject, :message

  def initialize(attributes = {})
    @attributes = attributes
  end

  validates :email,
    :presence   => true

  validates :subject,
    :presence   => true

  validates :message,
    :presence   => true


  def persist
    @persisted = true
  end

  def persisted?
    false
  end
end

… in my view file I have:

<%= form_for @contact_us, :url => contact_us_path do |f| %>
  <%= f.text_field :email %>
  <%= f.text_field :subject %>
  <%= f.text_area  :message %>
<% end %>

… in my router file I have:

match 'contact_us' => 'pages#contact_us', :via => [:get, :post]

… in my controller file I have:

class PagesController < ApplicationController
  def contact_us
    case request.request_method

    when 'GET'
      @contact_us = ContactUs.new

    when 'POST'
      @contact_us = ContactUs.new(params[:contact_us])
    end
  end
end

Using the above code, when I submit the form with at least a blank field (I do that in order to make it doesn’t pass validations) and the form is reloaded I don’t get those fields auto-populated. That is, after reloading the form (this happens after pressing the submit button) field values are set all to blank values.

What is the problem? Am I wrong on using the ActiveModel?

Answer 1

try to replace

<%= form_for @contact_us, :url => contact_us_path do |f| %>
   <%= f.text_field :email %>
   <%= f.text_field :subject %>
   <%= f.text_area  :message %>
<% end %> 

with

<%= form_for @contact_us, :url => contact_us_path do |f| %>
   <%= f.text_field :email, :value => @contact_us.email %>
   <%= f.text_field :subject, :value => @contact_us.subject %>
   <%= f.text_area  :message, :value => @contact_us.message %>
<% end %> 

EDIT:

I believe you’ll have to add the mass-assigment functionality yourself, like so:

def initialize(attributes = {})
  attributes.keys.each do |attr|
    self.class.send(:attr_accessor, attr.to_sym)
    instance_variable_set "@" + attr.to_s, attributes[attr.to_sym]
  end
end

You can actually skip this line: self.class.send(:attr_accessor, attr.to_sym) if you want to have attr_accessor :email, :subject, :message like you do already