ruby-on-rails - 从另一个模型触发模型中的状态更改

Question

Rails 新手和学习如何使用 state machines.怎么让一个 Actor 的粉丝从哭状态变成哭状态？

class Actor < ApplicationRecord
  include AASM

  has_many :fans 

  aasm do
    state :laughing, :initial => true
    state :crying

    event :cry do
      transitions :from => :laughing, :to => :crying
    end
    event :laugh do
      transitions :from => :crying, :to => :laughing
    end
  end
end  

class Fan < ApplicationRecord
  include AASM

  belongs_to :author 

  aasm do
    state :laughing, :initial => true
    state :crying

    event :cry do
      transitions :from => :laughing, :to => :crying
    end
    event :laugh do
      transitions :from => :crying, :to => :laughing
    end
  end
end

Answer 1

您可以使用 lifecycle callbacks在 actor 上触发更多方法:

class Actor < ApplicationRecord
  include AASM

  has_many :fans 

  aasm do
    state :laughing, :initial => true
    state :crying, :success => :fans_cry_too

    # ...
  end

  private

  def fans_cry_too
    fans.each(&:cry)
  end
end