我试图理解Rails的field_for,特别是嵌套资源的控制器应该是什么。 我的问题是,当我通过漫画形式创建带有漫画页面的漫画时,页面的图像不会保存。
我有用户,漫画和漫画页面。 以下是模型:
class User < ActiveRecord::Base
has_many :comics
has_many :comic_pages, through: :comics
end
class Comic < ActiveRecord::Base
belongs_to :user
has_many :comic_pages, :dependent => :destroy
accepts_nested_attributes_for :comic_pages
end
class ComicPage < ActiveRecord::Base
belongs_to :comic
end
这是Comic的表格,我也想在其中添加comic_pages:
<%= form_for ([@user, @comic]) do |f| %>
<%= f.text_field :title %>
<%= f.fields_for :comic_pages do |comic_page| %>
<%= comic_page.file_field :comic_page_image %>
<% end %>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
我对comics_controller(新建和创建操作)感到困惑。 如何将comic_page参数传递给此控制器???
def new
@user = current_user
@comic = @user.comics.new
@comic.comic_pages.build
end
def create
@user = current_user
@comic = @user.comics.new(comic_params)
@comic.comic_pages.build
respond_to do |format|
if @comic.save
format.html { redirect_to @user, notice: 'Comic was successfully created.' }
format.json { render action: 'show', status: :created, location: @user }
else
format.html { render action: 'new' }
format.json { render json: @comic.errors, status: :unprocessable_entity }
end
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_comic
@comic = Comic.find(params[:id])
end
# Never trust parameters from the scary internet, only allow the white list through.
def comic_params
params.require(:comic).permit(:title, :synopsis)
end
def comic_page_params
params.require(:comic_page).permit(:comic_page_image, :comic_image_file_name)
end
非常感谢!
---编辑---
在参数的答案之后,我使用它来创建以下创建操作:
def create
@user = current_user
@comic = @user.comics.new(comic_params)
i = 0
until i = 1
@comic_page = @comic.comic_pages.new(comic_params[:comic_pages_attributes]["#{i}"])
@comic_page.save
i += 1
end
respond_to do |format|
if @comic.save
...
end
end
end
您需要在控制器的comic_params
部分中允许要保存的comic_pages
中的字段
params.require(:comic).permit(:title, :synopsis, comic_pages_attributes: [:comic_page_image])