Question

我有两张表：User有一个Account，Account belongs_to User。当我想从字段“about”（表Accounts）中获取某些值时，我对undefined method'有一个问题“about nil:NilClass”。挑战在于获取关注者列表并从另一个表中获取他们的头像或“关于”的信息，并在View中输出。

我在控制器中的方法

 def list_of_follower
   @followers_id = Follow.select("follower_id ").where("followable_id = ?", current_user)
   @followers = User.where("id in (?)", @followers_id)
   @followables_id = Follow.select("followable_id").where("follower_id = ?", current_user)
   @followables = User.where("id in (?)", @followables_id)
end

查看list_of_follower.html.haml

%h1 My followers
 - @followers.each do |f|
  %ul.list-group
    %li.list-group-item
      %p=f.name
      %p=f.account.about
%h1 I'm follower
- @followables.each do |followable|
  %ul.list-group
%li.list-group-item
  %p=followable.name
  %p=followable.account.about

Create_Accounts.rb

class CreateAccounts < ActiveRecord::Migration
  def change
    create_table :accounts do |t|
      t.belongs_to :user, index: true
      t.text :about
      t.timestamps null: false
    end
 end
end

User.rb

class User < ActiveRecord::Base
 acts_as_followable
 acts_as_follower
 acts_as_liker
 has_one :account
 has_many :posts
 has_many :comments

accepts_nested_attributes_for :account
devise :database_authenticatable, :registerable,
     :recoverable, :rememberable, :trackable, :validatable

def email_required?
  false
end

def email_changed?
  false
end

 validates :login, :email, uniqueness: true
end

Account.rb

class Account < ActiveRecord::Base
 belongs_to :user
  mount_uploader :avatar, AvatarUploader
 end

表User内容显示没有问题（工作请求），但与之关联的表的内容没有显示，有什么问题？

Answer 1

我认为，问题不是每个用户都有帐户。你可以试试这个：

%p=f.account.try(:about)

nill类的未定义方法'about'

1 个答案: