How can I make a check box default to being “checked” in Rails 1.2.3?

Question

How can I make a check box default to being \"checked\" when it is initially displayed?

I\'ve not found a \"Rails\" way to do this (that works) so I did it with JavaScr

Answer 1

This works on Rails 2.3.x and Rails 3.0.x!

On action new in the controller, the check box is set to true.

# in the controller
def new
  @user = Person.find(:first)
  @user.active = true
end

In the form: the check box is checked on creation (by call new) but if the validation fails the check box remains set with the value that the user has post.

# in the view
<%= form_for ..... |f| %>
  ...
  <%= f.check_box :active %>
  ...
<% end %>

An other way, but not so good (if you want to change the logic you have to make a new migration) is to set :default => 1 in the migration of the given model and attribute.

class CreatePeople < ActiveRecord::Migration
  def self.up
    create_table :people do |t|
      ...
      t.boolean    :active,             :null => false,
                                        :default => 1
      t.timestamps
    end
  end

  def self.down
    drop_table :people
  end
end