Validation doesn't work (newbie in Rails)

Hi guys,

I am newbie in Rails world and I am using the Agile Web Development with Rails book to learn Rails.

I am trying to create a simple example using validation, actually only one field on the User Interface and this field uses the validates_presence_of validation.

Although this is a simple example, it doesn't work for me. Below following the source code of the VIEW, CONTROLLER, MODEL.

View (index.html.erb) <h1>Products#index</h1> <%= error_messages_for :product %> <% form_for :product,:url => {:action => :create} do |form| %>   Name: <%= form.text_field :name, :size => 30 %><br />   <%= submit_tag %> <% end %>

Controller (products_controller.rb) class ProductsController < ApplicationController

  def index   end

  def create     @product = Products.new(params[:product])   end end

Model (products.rb) class Products < ActiveRecord::Base   validates_presence_of :name, :message => "This is a required field" end

The only problem I can see off hand is that you might need to change your create action:

  def create     @product = Products.new(params[:product])     if @product.save        redirect_to :action => :list     else        render :action => :index     end   end