accept_nested_attributes_for + reject_if +未保存的子对象的显示错误

Question

I have a 'Parent' has-many 'Children' relationship among 2 models. im using accept_nested_attributes_for n the 'reject_if' feature. i want to display the a error message as "2 Child objects could not be saved." when the parent model is saved.

Answer 1

You can use validates_associated to bring up validation errors if any of the children are invalid. I think if you are using reject_if it won't actually build the child object, so you might need to remove the reject_if condition for the validation errors on the child to be shown.

Class Parent
  has_many :children
  validates_associated :children
end

class Child
  belongs_to :parent
end

More info here: http://api.rubyonrails.org/classes/ActiveRecord/Validations/ClassMethods.html