Question

I’ve two models:

The first model:

class Url < ActiveRecord::Base
  attr_accessible :code, :target, :user_id, :user
  belongs_to :user, :dependent => :destroy
end

rails console

1.9.3p125 :001 > Url
 => Url(id: integer, user_id: integer, code: string, target: string, created_at: datetime, updated_at: datetime)

The second model:

class User < ActiveRecord::Base
  attr_accessible :description, :status, :username
  has_many :urls

  validates :username,
    :presence => true,
    :uniqueness => true

  def to_s
    username
  end
end

rails console

1.9.3p125 :002 > User
 => User(id: integer, username: string, status: integer, description: text, created_at: datetime, updated_at: datetime)

Now i have a form, for creating an url:

<%= form_for(@url) do |f| %>
  <% if @url.errors.any? %>
    <div id="error_explanation">
      <h2><%= @url.errors.count %> Error(s):</h2>

      <ul>
      <% @url.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>

   <div class="field">
    <%= f.label :user_id %><br />
    <%= f.text_field :user_id %>
  </div>

  <div class="field">
    <%= f.label :code %><br />
    <%= f.text_field :code %>
  </div>
  <div class="field">
    <%= f.label :target %><br />
    <%= f.text_field :target %>
  </div>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

To increase the user-friendliness I want to exchange the field user_id with the field username. What steps are necessary to do?

Thanks!

Answer 1

You could use the collection_select helper to show a select box containing your users:

<%= f.collection_select(:user_id, User.all, :id, :username, :prompt => true) %>

This renders something like:

<select name="url[user_id]">
  <option value="">Please select</option>
  <option value="1">One User</option>
  <option value="2">Another User</option>
  <option value="3">...</option>
</select>