我正在构建一个具有语言模型，问题模型和答案模型的应用程序。我想在一个“我的问题”索引视图页面上显示问题和答案列表，分为以下几类：
我是编程新手，我不确定在Rails中研究“类别”这个词是否适合这个词，但我无法通过这种方式找到任何有用的信息。任何见解都将非常感谢！
以下是我的路线：
Languagecheck::Application.routes.draw do
devise_for :users
resources :users
resources :languages do
resources :questions, except: [:index] do
resources :answers
end
end
resources :questions, only: [:index, :new, :create]
get 'about' => 'welcome#about'
root to: 'welcome#index'
end
这是我的问题模型：
class Question < ActiveRecord::Base
require 'obscenity/active_model'
has_many :answers, dependent: :destroy
accepts_nested_attributes_for :answers, :reject_if => :all_blank, :allow_destroy=>true
belongs_to :user
belongs_to :language
default_scope { order('created_at DESC') }
validates :body, obscenity: true
validates :body, length: { minimum: 10, maximum: 160 }, presence: true
validates :user, presence: true
end
这是我的答案模型：
class Answer < ActiveRecord::Base
require 'obscenity/active_model'
belongs_to :question
belongs_to :user
validates :name, obscenity: true
validates :body, length: { minimum: 1, maximum: 160 }, presence: true
end
我的用户模型已设置，用户有许多问题和答案。
这是我的问题控制器：
class QuestionsController < ApplicationController
before_action :set_language, except: [:index]
before_action :set_question, only: [:show, :edit, :update, :destroy]
def index
@questions = current_user.questions
end
def show
@question = Question.find(params[:id])
@answer = Answer.new
end
def new
@question = Question.new
authorize @question
end
def edit
@question = Question.find(params[:id])
authorize @question
end
def update
@question = Question.find(params[:id])
authorize @question
if @question.update_attributes(question_params)
flash[:notice] = "Question was updated."
redirect_to [@language, @question]
else
flash[:error] = "There was an error saving the question. Please try again."
render :edit
end
end
def create
@question = Question.new(question_params)
@question.language = @language
@question.user = current_user
authorize @question
if @question.save
flash[:notice] = "Question was saved."
redirect_to [@language, @question]
else
flash[:error] = "There was an error saving the question. Please try again."
render :new
end
end
def destroy
@question.destroy.find(params[:id])
respond_to do |format|
format.html { redirect_to questions_url }
format.json { head :no_content }
end
end
private
def set_question
@question = Question.find(params[:id])
end
def question_params
params.require(:question).permit(:id, :body)
end
def set_language
@language = Language.find(params[:language_id])
end
end
这是我的答案控制器：
class AnswersController < ApplicationController
before_action :set_language_and_question
before_action :set_answer, only: [:show, :edit, :update, :destroy]
def index
@answers = Answer.all
end
def show
end
def new
@answer = Answer.new
end
def edit
end
def create
@answer = Answer.new(answer_params)
@answer.question = @question
@answer.user = current_user
respond_to do |format|
if @answer.save
format.html { redirect_to [@language, @question], notice: 'Answer was successfully created.' }
format.json { render action: 'show', status: :created, location: @answer }
else
format.html { redirect_to [@language, @question], error: 'Answer was not successfully created.' }
format.json { render json: @answer.errors, status: :unprocessable_entity }
end
end
end
def update
respond_to do |format|
if @answer.update(answer_params)
format.html { redirect_to @answer, notice: 'Answer was successfully updated.' }
format.json { head :no_content }
else
format.html { render action: 'edit' }
format.json { render json: @answer.errors, status: :unprocessable_entity }
end
end
end
def destroy
@answer.destroy
respond_to do |format|
format.html { redirect_to answers_url }
format.json { head :no_content }
end
end
private
def set_answer
@answer = Answer.find(params[:id])
@answer ||= @question.answers.new
end
def answer_params
params.require(:answer).permit(:id, :body)
end
def set_language_and_question
@language = Language.find(params[:language_id])
@question = Question.find(params[:question_id])
end
end
这是“我的问题”视图（目前仅列出所有问题）：
<div class="row">
<div class="col-md-8">
<h3>My Unanswered Questions</h3>
<% @questions.each do |question| %>
<div class="media">
<div class="media-body">
<h4 class="media-heading">
<p><%= question.language ? link_to(question.body, [question.language, question]) : question.body %></p>
</h4>
<small>
submitted <%= time_ago_in_words(question.created_at) %> ago by <%= question.user.name %> <br/>
<%= question.answers.count %> Answers
</small>
</div>
</div>
<% end %>
</div>
<br/>
<br/>
<div class="col-md-4">
<%= link_to "Ask a New Question", new_question_path, class: 'btn btn-success' %>
</div>
</div>
<div class="row">
<div class="col-md-8">
<h3>My Answered Questions</h3>
<% @questions.each do |question| %>
<div class="media">
<div class="media-body">
<h4 class="media-heading">
<p><%= question.language ? link_to(question.body, [question.language, question]) : question.body %></p>
</h4>
<small>
submitted <%= time_ago_in_words(question.created_at) %> ago by <%= question.user.name %> <br/>
<%= question.answers.count %> Answers
</small>
</div>
</div>
<% end %>
</div>
</div>
<div class="row">
<div class="col-md-8">
<h3>Questions I Answered</h3>
<% @questions.each do |question| %>
<div class="media">
<div class="media-body">
<h4 class="media-heading">
<p><%= question.language ? link_to(question.body, [question.language, question]) : question.body %></p>
</h4>
<small>
submitted <%= time_ago_in_words(question.created_at) %> ago by <%= question.user.name %> <br/>
<%= question.answers.count %> Answers
</small>
</div>
</div>
<% end %>
</div>
</div>
答案 0 :(得分：0)
瓦莱丽，
像马特一样，我并不完全确定你的意思＆＃34;分类＆＃34;。听起来您希望能够遍历给定页面上的各种问题组。所以像这样：<% @user.unanswered_questions.each do |question| %>
...
<% end %>
<% @user.answered_questions.each do |question| %>
...
<% end %>
<% @user.answers.each do |answer| %>
...
<% end %>
在一个视图上。
如果这就是你的意思，那么马特的建议听起来就像是正确的。您只需在question.rb上创建范围或方法即可实现此目的。我实际上是在创建以下范围：
scope :answered, -> { joins(:answers) }
scope :unanswered, -> { where.not(id: joins(:answers).pluck(:id)) }
然后你可以@user.questions.answered和@user.questions.unanswered（与上面略有不同，但两者都是一个选项）。第二个有点复杂。基本上，我们通过答案（joins(:answers)）获取问题，获取他们的ID（pluck(:id)），然后使用不在该集合中的ID来抓取所有问题（即没有答案的那些问题） ）。我认为这是有效的，但我还没有对此进行测试。有关详细信息，请查看AR文档：http://guides.rubyonrails.org/active_record_querying.html
这是你的意思吗？通常在Rails中，如果这样的问题涉及对数据进行分段（或分类），您需要考虑将此功能推送到模型层，在那里它是最抽象的。
另请注意，这些范围也可能是类方法。只要他们返回AR关系，就没有什么大不同，所以他们可以被链接＃34;。