在 a 中使用复选框属于并具有一种关系

Question

在我的“帐户”模型的“显示”页面上，我有一个“清单”模型。我希望能够在帐户的显示页面中检查清单上的每个布尔值。 我收到以下错误：

NoMethodError in Accounts#show
undefined method `model_name' for NilClass:Class

• app/models/account.rb

  class Account < ActiveRecord::Base
    has_one :checklist
  end
  

• app/models/checklist.rb

  class Checklist < ActiveRecord::Base
    belongs_to :account
    belongs_to :user
  
    validates :account_id, :presence => true
    validates :user_id, :presence => true
  end
  

• app/models/user.rb

  class User < ActiveRecord::Base
    has_many :checklists
  end
  

• app/controllers/account_controller.rb

  class AccountController < ApplicationController
    def show
      @account = Account.find(params[:id])
      @checklist = @account.checklist
    end
  end
  

• app/views/account/show.html.erb

  <% simple_form_for(@checklist) do |checklist| %>
    <div>
      <%= checklist.user.email %>
      <div class="pull-right">
        <%= checklist.created_at.strftime("%b. %d %Y") %>
      </div></br>
      <ul>
        <li><%= checklist.contract_signed %></li>
        <li><%= checklist.contract_details %></li>
        <li>…</li>
      </ul>
      <%= f.submit "Update", class: 'btn' %>
    </div>
  <% end %>
  

• app/controllers/checklists_controller.rb

  class ChecklistsController < ApplicationController
    before_filter :authenticate_user!
  
    def create
      @account = Account.find(params[:account_id])
      @checklist = @account.checklist.build(params[:checklist])
      @checklist.user = current_user
  
      respond_to do |format|
        if @checklist.save
          format.html { redirect_to(@account, :notice => 'Checklist Saved.') }
        else
          format.html { redirect_to(@account, :notice => 'There was an errors') }
        end
      end
    end
  
  
    def destroy
      @checklist = current_user.checklists.find(params[:id])
      @account = Account.find(params[:account_id])
      @checklist.destroy
  
      respond_to do |format|
        format.html { redirect_to @account }
      end
    end
  end
  

Answer 1

我不确定我是否完全理解您的视图逻辑，但我认为您需要做的是在进入控制器的创建部分之前构建清单。

例如

  def show
    @account = Account.find(params[:id])
    @checklist = @account.build_checklist
  end

这将允许您调用正在显示的视图中的属性。

你也可以调整create方法，使用new代替build

def create
  @account = Account.find(params[:account_id])
  @checklist = @account.checklist.new(params[:checklist])
  @checklist.user = current_user

  respond_to do |format|
      if @checklist.save
        format.html { redirect_to(@account, :notice => 'Checklist Saved.') }
      else
        format.html { redirect_to(@account, :notice => 'There was an error saving your comment (empty comment or comment way to long).') }
      end
  end
end

希望这会有所帮助:)