Question

创建新教程时，我正在尝试实现一个包含视频的表单。问题是我每次访问页面时都不会呈现表单。有人可以帮忙吗？

这是myapp / views / admin / tutorials / new.html.erb

<h2>New Tutorial</h2>
<%= form_for [:admin, @tutorial] do |f| %>
  <%= f.label :title %>
  <%= f.text_field :title, class: "block col-4 field" %>
  <%= f.label :description %>
  <%= f.text_area :description, class: "block col-4 field"  %>
  <%= f.label :thumbnail %>
  <%= f.text_field :thumbnail, class: "block col-4 field"  %>

  <h3>Videos</h3>

  <%= f.fields_for :videos do |builder| %>
    <%= builder.label :youtube_url %>
    <%= builder.text_field :youtube_url, class: "block col-4 field" %>
    <%= builder.label :video_id %>
    <%= builder.text_field :video_id, class: "block col-4 field" %>
  <% end %>

  <%= f.submit "Save", class: "mt2 btn btn-primary mb1 bg-teal"  %>
<% end %>

这是我的视频模型

class Video < ApplicationRecord
  has_many :user_videos
  has_many :users, through: :user_videos
  belongs_to :tutorial

  validates_presence_of :position 
end

还有我的教程模型

class Tutorial < ApplicationRecord
  has_many :videos, ->  { order(position: :ASC) }, dependent: :destroy
  acts_as_taggable_on :tags, :tag_list
  accepts_nested_attributes_for :videos

  scope :without_classroom, -> { where(classroom: false) }
end

我的控制器：

 class Admin::TutorialsController < Admin::BaseController

  def new
    @tutorial = Tutorial.new
  end

  def create
    @tutorial = Tutorial.new(tutorial_params)
    if @tutorial.save
      flash[:success] = "Successfully created tutorial!"
      redirect_to tutorial_path(@tutorial)
    else
      render :new
    end
  end

  def edit
    @tutorial = Tutorial.find(params[:id])
  end

  def update
    tutorial = Tutorial.find(params[:id])
    if tutorial.update(tutorial_params)
      flash[:success] = "#{tutorial.title} tagged!"
    end
    redirect_to edit_admin_tutorial_path(tutorial)
  end

  private
  def tutorial_params
    params.require(:tutorial).permit(:tag_list, :title, :description, :thumbnail)
  end
end

Answer 1

什么都没呈现的原因是videos关联为空。例如，如果您在@tutorial.videos.build控制器操作中添加new，那么您将获得一组字段，并且如果关联中有多个视频（无论是否持续），您将获得一组每个视频的字段数。

Rails fields_for无法在页面上呈现

1 个答案: