关联无效。确保accepts_nested_attributes_for用于:问题关联

时间:2014-05-13 08:27:04

标签: ruby-on-rails ruby-on-rails-4 nested-forms nested-form-for

我正在rails 4中构建嵌套表单。我不断收到此错误

我的_form.html.erb为

    <%= nested_form_for (@project) do |f| %>
    <% if @project.errors.any? %>
    <div id="error_explanation">
    <h2><%= pluralize(@project.errors.count, "error") %> prohibited this project from being saved:</h2>

    <ul>
    <% @project.errors.full_messages.each do |message| %>
      <li><%= message %></li>
     <% end %>
     </ul>
     </div>
    <% end %>

    <div class="field">
    <%= f.label :name %><br>
    <%= f.text_field :name %>
    </div>

    <%= f.fields_for :questions do |builder| %>
    <%= render "question_fields", :f => builder %>
    <% end %>

    <div class="actions">
    <%= f.submit %>
    </div>
    <% end %>

_question.html.erb

      <p>
            <%= f.label :content, "Question" %><br />
            <%= f.text_area :content, :rows => 3 %><br />
            <%= f.label :subject, "Question" %><br />
            <%= f.text_field :subject %><br />
            <%= f.link_to_remove "Remove this task" %>
            <p><%= f.link_to_add "Add a questions",:questions %></p>
     </p>

project.rb

       has_many :questions, :dependent => :destroy

       accepts_nested_attributes_for :questions, :reject_if => lambda { |a| a[:content].blank? }, :allow_destroy => true

修改

question.rb

      class Question < ActiveRecord::Base

       belongs_to :project

       end

项目控制器

      def new
      @project = Project.new
       3.times do
       question = @project.questions.build
        end
      def project_params
      params.require(:project).permit(:name)
      end

        def create
        @project = Project.new(project_params)

        respond_to do |format|
        if @project.save
        format.html { redirect_to @project, notice: 'Project was successfully created.' }
         format.json { render :show, status: :created, location: @project }
        else
         format.html { render :new }
        format.json { render json: @project.errors, status: :unprocessable_entity }
       end
      end

我用“ nested_form ”gem给出错误Invalid association. Make sure that accepts_nested_attributes_for is used for :questions association.

请帮我摆脱这个错误

问题控制器def: -

      def question_params
      params.require(:question).permit(:project_id, :subject, :content)
      end

1 个答案:

答案 0 :(得分:1)

你的问题可能是你的强参数

尝试将projects_controller中的project_params更改为

def project_params

params.require(:project).permit(:name,questions_attributes: [:project_id,:subject,:content])

end

而且,您的控制器代码应如下所示

def new
@project = Project.new
3.times do
@question = @project.questions.build
end


def create
@project = Project.new(project_params)

respond_to do |format|
if @project.save
format.html { redirect_to @project, notice: 'Project was successfully created.' }
format.json { render :show, status: :created, location: @project }
else
format.html { render :new }
format.json { render json: @project.errors, status: :unprocessable_entity }
end
end

private

def project_params

params.require(:project).permit(:name,questions_attributes: [:project_id,:subject,:content])

end

此外,您必须寻找 Strong Parameters with accepts_nested_attributes_for

<强>更新

尝试将_form.html.erb更改为

<%= nested_form_for(@project) do |f| %>
    <% if @project.errors.any? %>
    <div id="error_explanation">
    <h2><%= pluralize(@project.errors.count, "error") %> prohibited this project from being saved:</h2>

    <ul>
    <% @project.errors.full_messages.each do |message| %>
      <li><%= message %></li>
     <% end %>
     </ul>
     </div>
    <% end %>

    <div class="field">
    <%= f.label :name %><br>
    <%= f.text_field :name %>
    </div>

    <%= f.fields_for :questions do |builder| %>
    <%= render "question_fields", :ff => builder %> #changed to ff to avoid confusion
    <% end %>
    <p><%= f.link_to_add "Add a questions",:questions %></p> #this line it should be here.
    <div class="actions">
    <%= f.submit %>
    </div>
    <% end %>

您的_question_fields.html.erb

<p>
    <%= ff.label :content, "Question" %><br />
    <%= ff.text_area :content, :rows => 3 %><br />
    <%= ff.label :subject, "Question" %><br />
    <%= ff.text_field :subject %><br />
    <%= ff.link_to_remove "Remove this task" %>       
</p>