Question

我正在做一个在线单词学习项目，我想提供一个搜索功能，您可以在其中按课程，单词和学习状态（已学习/未学习）过滤单词。完成课程和单词的过滤。我陷入了最后的过滤条件。我正在使用作用域，但学习状态的参数似乎无法进入作用域，“ words”表和“ user_words”表将无法连接（我首先尝试了这两个表）。

这是我的桌子：

create_table "users" do |t|
  t.string "username"
end

create_table "words" do |t|
  t.string "name"
  t.integer "lesson_id"
end

create_table "user_words" do |t|
  t.integer "user_id"
  t.integer "word_id"
  t.boolean "status"
end

我的模型：

class User < ApplicationRecord
  has_many :user_words
end

class Word < ApplicationRecord
  has_many :user_words

  scope :order_name_asc, -> {order name: :asc}

  scope :search_prefix, -> prefix {where "name like ?", "#{prefix}%"}

  scope :search_lesson, -> lesson_id {
    where("lesson_id = ?", lesson_id) if lesson_id.present?}

  # Is the problem here?
  scope :search_learned, -> (learned) do
    joins(:user_words).where("user_words.status = ?", 
    learned[:user_word_status].to_i) if learned[:user_word_status]
  end
end

class UserWord < ApplicationRecord
  belongs_to :user
  belongs_to :word
end

我的控制器

class StaticPagesController < ApplicationController
  before_action :load_lessons, only: :home
  before_action :load_user_words, only: :home

  def home
    @words = Word.search_learned(learned: params[:learned]) #or the problem's here
      .search_lesson(params[:lesson_id])
      .search_prefix(params[:prefix]).order_name_asc
      .paginate page: params[:page]
  end
end

和视图：

# Lesson filter option:
<%= select_tag :lesson_id,
  grouped_options_for_select(@categories.map {|category| 
    [category.name,category.lessons.map {|lesson| [lesson.name, 
      lesson.id]}]}),
  include_blank: t(".all_lessons"), class: "btn btn-primary" %>

# Learning status filter option (is the problem here?):
<%= select_tag :learned, 
  options_for_select(@user_words.map(&:status)),
  include_blank: t(".learned"), class: "btn btn-secondary" %>

# Text input fied, submit button and the word list:
<%= text_field_tag :prefix, params[:prefix],
  placeholder: t(".search"), class: "form-control" %>
<%= submit_tag t(".search"), name: nil, class: "btn btn-success" %>

<% @words.each do |word| %>
  <%= link_to word.name, "#" %>
<% end %>

Rails-使用范围过滤多个表

0 个答案: