How to edit multiple models in one form?

Question

I got a task from my trainer. I want to edit two models in one form. For example, we have two entities student and address. In the new student part i want to add both student details and address. How can i achieve this through scaffolding in ruby on rails?

Answer 1

You can use accepts_nested_attributes_for and fields_for to build a form to create two model at same time, so you can edit them too. This kind of form called nested form.

Here is a reference for you about Nested form,.

Answer 2

We can edit the multiple models like this..

in students/edit.rhtml

Edit Student

 <%= error_messages_for :student %>

 <%= start_form_tag :action => 'update', :id => params[:id] %>


 <p>
  Student Name:
  <%= text_field :student, :name %>
  </p>

 <h2>Address</h2>
  <% for @address in @student.addresses %>
  <%= error_messages_for :address %>
  <% fields_for "address[]" do |f| %>
  <p><%= f.text_field :name %></p>
  <% end %>
  <% end %>

 <p><%= submit_tag 'Update' %></p>
  <%= end_form_tag %>

Answer 3

I am not sure about scaffolding, but the expected behavior can be achieved by using form_tag instead of form_for.

<%= form_tag :url => , :html => {:id=> , :method => , :class => ""} do %>
  <% text_field_tag <id>, <default_value>, :name=>"student[name]" %>
  <% text_field_tag <id>, <default_value>, :name=>"student[age]" %>
  <% text_field_tag <id>, <default_value>, :name=>"address[street]" %>
  <% text_field_tag <id>, <default_value>, :name=>"address[city]" %>
  <% text_field_tag <id>, <default_value>, :name=>"address[state]" %>
  <% text_field_tag <id>, <default_value>, :name=>"address[country]" %>
  <%= submit_tag 'save' %>
<% end %>

the params will then nicely be grouped in a hash like

{'student' => {'name' => , 'age' => }, 'address' => {'street' => , 'city' =>  . . .}} 

which you can parse to update both the models