CODEWITHSUNDEEP
ruby-on-railsrubyforms
tsm
tsm

Reputation: 3658

Rails form_for and text_field without model attribute

I'm writing a form for users to register their products with. I already have class User has_many :products and class Product belongs_to :user; attr_accessible :serial_number. So the idea is that the user enters the serial number in the form and I call @user.products << Product.find_by_serial_number params[:serial_number] or somesuch.

It seemed sensible to add this as a register action to the UsersController:

resources :users do
  member do
    get 'register'
  end
end

And I have the following in register.html.erb:

5:   <%= render 'shared/error_messages' %>
6: 
7:   <%= f.label :serial_number, "Serial number" %>
8:   <%= f.text_field :serial_number %>
9: 
10:   <%= f.submit "Register product" %>
11: <% end %>

This throws the error:

undefined method `serial_number' for #<User:0x000000060b1d40>
extracted source (around line #8):
...

So...a) How do I stop this error? b) Umm...what's going to happen after the submit button is pressed? I'm assuming it'll call the update action (which is also used by the edit form)...should I make that fatter to deal with both possiblities? Or make a new action? (If so, how do I reroute the form to point to that?) c) Error-handling (putting in an invalid serial number) is best handled in the controller, not the model, right?

Thanks.

Upvotes: 5

Views: 4353

Answers (2)

zeantsoi
zeantsoi

Reputation: 26193

The error being thrown indicates that there's no method serial_number for the User model... which there isn't. The method is actually attached to the Product model, but the form in register.html.erb is for User. You can resolve this by using a nested form.

First, ensure that User can accept nested attributes for Product:

# app/models/user.rb
has_many :products
accepts_nested_attributes_for :products

Then, make your form into a nested form:

# app/views/users/register.html.erb
<%= form_for(@user) do |f| %>

  <%= f.fields_for :products do |e| %>
    <%= e.label :serial_number, "Serial number" %>
    <%= e.text_field :serial_number %>
  <% end %>

  <%= f.submit "Register product" %>

<% end %>

Upvotes: 1

OneChillDude
OneChillDude

Reputation: 8006

You can only use the form helper for attributes of the model. In this case you will need to use the full method.

 = label_tag :serial_number, 'Serial number'
 = text_field_tag :serial_number

Upvotes: 4

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