0
我需要在保存一系列子級時將更新的參數傳遞迴父級模型。
例如，如果通過一個項目爲每個任務保存一堆僱員，我需要讓項目知道其中一些任務的標題已經更改，然後我需要收集所有更改的標題並在ProjectObserver。這可能嗎？rails - 如何將更改傳回父級模型
我意識到可能沒有辦法讓我按照我的方式工作。如果不是，我很樂意聽到關於我如何能夠解決這個問題的建議。
以下是我已經沒有任何成功的嘗試：
class Employee < ActiveRecord::Base
has_many :employee_tasks
has_many :tasks, :through => :employee_tasks
accepts_nested_attributes_For :employee_tasks
accepts_nested_attributes_For :tasks
end
class Project < ActiveRecord::Base
attr_accessor :changed_employees
has_many :tasks
end
class Task < ActiveRecord::Base
has_many :employee_tasks
has_many :employees, :through => :employee_tasks
belongs_to :project
accepts_nested_attributes_For :employee_tasks
end
class EmployeeTask < ActiveRecord::Base
#this is what I want to accomplish
before_save do
if self.employee_id_changed
self.task.project.changed_employees ||= []
self.task.project.changed_employees << self.employee_id_changed
end
end
belongs_to :task
belongs_to :employee
end
class ProjectObserver < ActiveRecord::Observer
observe :project
def after_save(project)
puts project.changed_employees
# should print out the changed attributes loaded from EmployeeTask
#send a single email with all the updated titles (not one email for each change)
end
end