problem about accepts_nested_attributes_for

rubyonrails-talk
1

I make two classes job and step, its associate with accepts_nested_attributes_for, has_many and belongs_to. liks:

class Job < ActiveRecord::Base has_many :steps, :dependent => :destroy accepts_nested_attributes_for :steps

validate :job_validate , :on => :create def job_validate p “job validate” end end

class Step < ActiveRecord::Base belongs_to :job

here just test if called this validates_presence_of

validates_presence_of :name , :if => Proc.new { |step| p " step name validates_presence_of" } validate_on_create :step_validate

private def step_validate p self p “step validate” end end

Tow migtations links: class CreateJobs < ActiveRecord::Migration def self.up create_table :jobs do |t| t.string :name

  t.timestamps
end

end

def self.down drop_table :jobs end end

class CreateSteps < ActiveRecord::Migration def self.up create_table :steps do |t| t.string :name t.references :job t.timestamps end end

def self.down drop_table :steps end end

My problem is that when i testing them in script/console as follow: shell:$ script/console Loading shelllocal environment (Rails 2.3.5)

job = Job.new => #<Job id: nil, name: nil, created_at: nil, updated_at: nil> job.steps.build => #<Step id: nil, name: nil, job_id: nil, created_at: nil, updated_at: nil> job.save " step name validates_presence_of" #<Step id: nil, name: nil, job_id: nil, created_at: nil, updated_at:

“step validate” " step name validates_presence_of" #<Step id: nil, name: nil, job_id: nil, created_at: nil, updated_at:

“step validate” “job validate” => true

As you see the “step validate” called two times.I think “step validate” be called once is correct. I don’t know why its called tow times? Who can help me?

thank you !