active_hash를 사용하여 도도부현의 선택란을 만듭니다

이번에 나는 흔히 볼 수 있는 도도부현의 선택란을 만들고 싶다

①　active_hash 배포

gem 'active_hash'

$ bundle install

② 관련 모델의prefecture_id:integer 추가

내 경우pet모델에 추가합니다.
db

  prefecture_id :integer

③ prefecture 모형을 수동으로 만들기

모델에서prefecture.rb 파일을 직접 제작하여 내용을 기술하다.
prefecture.rb

class Prefecture < ActiveHash::Base
  self.data = [
      {id: 1, name: '北海道'}, {id: 2, name: '青森県'}, {id: 3, name: '岩手県'},
      {id: 4, name: '宮城県'}, {id: 5, name: '秋田県'}, {id: 6, name: '山形県'},
      {id: 7, name: '福島県'}, {id: 8, name: '茨城県'}, {id: 9, name: '栃木県'},
      {id: 10, name: '群馬県'}, {id: 11, name: '埼玉県'}, {id: 12, name: '千葉県'},
      {id: 13, name: '東京都'}, {id: 14, name: '神奈川県'}, {id: 15, name: '新潟県'},
      {id: 16, name: '富山県'}, {id: 17, name: '石川県'}, {id: 18, name: '福井県'},
      {id: 19, name: '山梨県'}, {id: 20, name: '長野県'}, {id: 21, name: '岐阜県'},
      {id: 22, name: '静岡県'}, {id: 23, name: '愛知県'}, {id: 24, name: '三重県'},
      {id: 25, name: '滋賀県'}, {id: 26, name: '京都府'}, {id: 27, name: '大阪府'},
      {id: 28, name: '兵庫県'}, {id: 29, name: '奈良県'}, {id: 30, name: '和歌山県'},
      {id: 31, name: '鳥取県'}, {id: 32, name: '島根県'}, {id: 33, name: '岡山県'},
      {id: 34, name: '広島県'}, {id: 35, name: '山口県'}, {id: 36, name: '徳島県'},
      {id: 37, name: '香川県'}, {id: 38, name: '愛媛県'}, {id: 39, name: '高知県'},
      {id: 40, name: '福岡県'}, {id: 41, name: '佐賀県'}, {id: 42, name: '長崎県'},
      {id: 43, name: '熊本県'}, {id: 44, name: '大分県'}, {id: 45, name: '宮崎県'},
      {id: 46, name: '鹿児島県'}, {id: 47, name: '沖縄県'}
  ]

  include ActiveHash::Associations
  has_many :pets
end

pet 모델에도 관계 추가
pet.rb

class Pet < ApplicationRecord

  extend ActiveHash::Associations::ActiveRecordExtensions
  belongs_to_active_hash :prefecture

end

④ 매개변수: prefecture_id 추가

pets.controller.rb

  private

  def pet_params
    params.require(:pet).permit(:name, :prefecture_id)
  end
end

⑤ 추가 뷰

<%= form_with model: @pet, url: pets_path, method: :post, local: true do |f| %>
  <%= f.label :"都道府県" %>
  <%= f.collection_select :prefecture_id, Prefecture.all, :id, :name, prompt: "-- 選択してください--" %>
<%= end %>

완성했습니다