如何在Rails Admin关联模型中进行自定义下拉菜单

Question

Rails Admin has_many关联选项删除自定义

我想在Rails管理员选择下拉选项中进行一些更改。我有一些具有has_many关系的模型。

模型文件 post.rb

class Post < ApplicationRecord
    has_many :photos, dependent: :destroy
    accepts_nested_attributes_for :photos, allow_destroy: true
    def post_image
       photos&.first&.asset_url
    end
end

photo.rb

class Photo < ApplicationRecord
  belongs_to :post
end

homepage.rb

class Homepage < ApplicationRecord
    has_many :homepagepost
    has_many :posts,-> { order(likes_count: :desc) }, through: :homepagepost
end

homepagepost.rb

class Homepagepost < ApplicationRecord
    belongs_to :post
end

设置管理员配置 rails_admin.rb

config.model Homepage do
    label "Homepage Rows"
    edit do
      field :title_heading
      field :posts
      field :status
    end
    list do
      field :title_heading
      field :posts
      field :status
      field :created_at
      field :updated_at
    end
end

现在，我想在带有帖子ID的“帖子”下拉列表中显示帖子图像URL。我如何在Rails管理员中执行此操作？ 就像 Post＃1370 post_test.png

架构

create_table "photos", id: :serial, force: :cascade do |t|
    t.string "asset_url"
    t.integer "post_id"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.index ["post_id"], name: "index_photos_on_post_id"
end

create_table "posts", id: :serial, force: :cascade do |t|
    t.integer "user_id"
    t.text "description"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.index ["user_id"], name: "index_posts_on_user_id"
end 

create_table "homepageposts", force: :cascade do |t|
    t.integer "homepage_id"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.bigint "post_id"
    t.index ["post_id"], name: "index_homepageposts_on_post_id"
end

create_table "homepages", force: :cascade do |t|
    t.string "title_heading"
    t.integer "status"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
end

Answer 1

首先在rails admin初始化程序上进行配置，通常是在配置块内的config/initializers/rails_admin.rb上进行配置，该方法将在模型中用于确定要为每个对象显示的标题，如下所示：

RailsAdmin.config do |config|
  config.label_methods = [:rails_admin_title]
end

然后在您的帖子模型上定义该方法

class Post < ApplicationRecord
    has_many :photos, dependent: :destroy
    accepts_nested_attributes_for :photos, allow_destroy: true

    def rails_admin_title
      "<a href='#{post_image}'>Link</a>".html_safe
    end

    def post_image
      photos&.first&.asset_url
    end
end

您可能需要重新启动开发服务器才能看到此更改。