Question

我正在努力建立一种我认为理解的一对一关系......

我的用户表和配置文件表应该与一对一的关系链接，但是当我尝试调用它时，它会返回错误。

以下是我的模特：

    class Profile < ApplicationRecord
      mount_uploader :AvatarUploader
      belongs_to :user
    end



    class User < ApplicationRecord
      # Include default devise modules. Others available are:
      # :confirmable, :lockable, :timeoutable and :omniauthable
      devise :database_authenticatable, :registerable, :omniauthable,
             :recoverable, :rememberable, :trackable, :validatable,
             :confirmable
      acts_as_voter
      enum role: [:user, :admin]
      has_many :entries, dependent: :destroy
      has_many :reports, dependent: :destroy
      has_many :messages
      has_one :profile
    end

我的架构中的相关表格：

      create_table "profiles", force: :cascade do |t|
        t.text "bio"
        t.string "avatar"
        t.string "country"
        t.bigint "user_id"
        t.datetime "created_at", null: false
        t.datetime "updated_at", null: false
        t.index ["user_id"], name: "index_profiles_on_user_id"
      end




        create_table "users", force: :cascade do |t|
        t.string "email", default: "", null: false
        t.string "encrypted_password", default: "", null: false
        t.string "reset_password_token"
        t.datetime "reset_password_sent_at"
        t.datetime "remember_created_at"
        t.integer "sign_in_count", default: 0, null: false
        t.datetime "current_sign_in_at"
        t.datetime "last_sign_in_at"
        t.inet "current_sign_in_ip"
        t.inet "last_sign_in_ip"
        t.string "confirmation_token"
        t.datetime "confirmed_at"
        t.datetime "confirmation_sent_at"
        t.string "unconfirmed_email"
        t.datetime "created_at", null: false
        t.datetime "updated_at", null: false
        t.integer "role", default: 0
        t.integer "score", default: 0
        t.string "username"
        t.index ["email"], name: "index_users_on_email", unique: true
        t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
      end

所以我试图调用user.country，它返回no方法错误。我已经阅读了几个不同网站上的关系，但似乎无法注意到我做错了什么

由于

Answer 1

您的所有关联设置都是正确的，但我认为您稍微误解了rails中关联的工作方式。由于您拥有关联local background = display.newImageRect("blueBackground.png",642, 1040) background.x = display.contentCenterX background.y = display.contentCenterY local x = 15 local y=15 for i=15,25 do for j=15, 25 do local bubble = display.newImageRect("bubble.png", 23,23) bubble.x = i bubble.y = j j = j + 29 print("j",j) end i = i + 29 print("i",i) end和user has_one profile 您可以调用profile belongs_to user，它将返回与用户关联的配置文件对象。要访问个人资料中的@user.profile属性，您必须实际调用country。所以不要打电话

@user.profile.country

你必须使用

user.country

希望这有帮助。

Answer 2

通常你会想要打电话

user.profile.country

但是如果您想使用user.country，则必须将这些方法从Profile委托给User，如下所示：

   class User < ApplicationRecord
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable, :omniauthable,
         :recoverable, :rememberable, :trackable, :validatable,
         :confirmable
  acts_as_voter
  enum role: [:user, :admin]
  has_many :entries, dependent: :destroy
  has_many :reports, dependent: :destroy
  has_many :messages
  has_one :profile

  #delegate method call to profile, check the delegate document for more options.
  delegate :country, to: :profile


end

试图建立一对一的关系

2 个答案: