Ruby on Railsに小さなWebアプリがあり、アンティークドキュメントとドキュメントによって参照される場所が一覧表示されます。すでにドキュメントに添付されている場所を更新できますが、新しいドキュメントを作成しようとすると、次のエラーが発生します
undefined method `locations' for nil:NilClass
NilClassはLocationController＃newで発生します：
def new
@location = @document.locations.new
end
これは、そのような観点から呼び出されます
<%= form_for(@location,:url=>new_document_location_path(@document)) do |f| %>
<%= render :partial => "document_locations/form", :locals =>{:f=>f} %>
<%= f.submit "Save",:class=>"span2 btn" %>
<%end%>
そのため、何らかの理由で、@documentクラスがコントローラーによって参照されていません。フォーム内のドキュメント属性を表示できるため、クラスがビューとスコープにアクセスできることを知っています（例：<％= @ document.id％>
では、なぜコントローラーは@document変数を参照できないのでしょうか。これは、クラス変数を渡す方法にかかっていると思います。とにかく、私はいくつかのポインタに非常に感謝します。
これがモデルの定義方法です
class Document < ActiveRecord::Base
has_many :locations, :dependent => :destroy
end
class Location < ActiveRecord::Base
belongs_to :document
end
これが私のルートです
Pastpaper::Application.routes.draw do
# added in to test
match '/documents/:id/locations/create' => 'locations#create'
resources :documents do
collection do
match 'permanent_delete/:id' => 'documents#permanently_delete',:as => :permanent_delete
end
match '/authorinfo' => 'documents#authorinfo',:as => :authorinfo
match '/publicationinfo' => 'documents#publicationinfo',:as => :publicationinfo
match '/images' => 'documents#itemimages' ,:as => :itemimages
match '/locations' => 'documents#locations',:as => :locations
match '/itempeople' => 'documents#itempeople' ,:as => :itempeople
match '/people_facts_locations' => 'documents#people_facts_locations',:as => :people_facts_loc
resources :locations, :controller=>"locations"
resources :people ,:controller => "document_people"
resources :document_facts
resource :facts
resources :document_photos
end
resources :home do
collection do
get 'document_search','simple_location_search','date_search','simple_people_search','simple_organisation_search','document_filter'
get 'search_results'
post 'search_results'
end
end
match 'documents/publicationinfo/:id' => 'documents#publicationinfo',:as => :publicationinfo
match 'documents/update/publishinginfo/:id' => 'documents#publishinginfo',:as => :publishinginfo
match 'documents/document_image_remove/:id' => 'documents#remove_image',:as=>"remove_image"
match 'documents/make_primary_image/:id' => 'documents#make_primary_image',:as => :make_primary_image
match 'person_detail/:id' => 'documents#person_detail',:as=>'person_detail'
match 'about', :to=> 'pages#about'
match 'contact', :to => 'pages#contact'
match 'privacy', :to => 'pages#privacy'
match 'terms', :to => 'pages#terms'
match 'help', :to => 'pages#help'
namespace :admin do
resources :document_types
resources :statuses
resources :attribute_types
resources :event_types
resources :users
resources :orders
resources :documents
match 'restore_document/:id' => 'Documents#restore_document', :as => 'restore_document'
match 'report' => 'report#index' ,:as=>:report
match 'report/surname_report' => 'report#surname_report',:as=>:surname_report
match 'report/location_report' => 'report#location_report',:as=>:location_report
end
root :to => 'home#index'
end
そして、これが関連するコントローラーです：DocumentController
class DocumentsController < ApplicationController
before_filter :prepare_document ,:only => [:locations]
def locations
@locations = @document.locations.order("id asc")
@location = @document.locations.new
end
private
def prepare_document
if params[:id]
@document = Document.find(params[:id], :include => [:document_attributes])
elsif params[:document_id]
@document = Document.find(params[:document_id], :include => [:document_attributes])
end
end
end
LocationsController
class LocationsController < ApplicationController
before_filter :prepare_document
def new
@location = @document.locations.new
end
def create
@location = @document.locations.build
if @location.save
redirect_to document_locations_url(@document)
else
render "new"
end
end
def update
@location = @document.locations.find(params[:id])
if @location.update_attributes(params[:location])
redirect_to document_locations_url(@document)
else
render "edit"
end
end
def prepare_document
if params[:document_id]
if current_user.is_admin?
@document = Document.find(params[:document_id], :include => [:document_attributes])
else
@document = current_user.documents.find(params[:document_id], :include => [:document_attributes])
end
end
end
end
これが私のルートがすくい上がる方法です
logout GET /logout(.:format) {:action=>"destroy", :controller=>"sessions"}
login POST /login(.:format) {:action=>"create", :controller=>"sessions"}
forgot_password /forgot_password(.:format) {:action=>"new", :controller=>"password_resets"}
user_home GET /profile(.:format) {:action=>"index", :controller=>"users"}
deactivateaccount /account/deactivate(.:format) {:controller=>"users", :action=>"accountdeactivate"}
changepassword /account/changepassword(.:format) {:controller=>"users", :action=>"changepassword"}
register /user/registration(.:format) {:controller=>"users", :action=>"new"}
users GET /users(.:format) {:action=>"index", :controller=>"users"}
POST /users(.:format) {:action=>"create", :controller=>"users"}
new_user GET /users/new(.:format) {:action=>"new", :controller=>"users"}
edit_user GET /users/:id/edit(.:format) {:action=>"edit", :controller=>"users"}
user GET /users/:id(.:format) {:action=>"show", :controller=>"users"}
PUT /users/:id(.:format) {:action=>"update", :controller=>"users"}
DELETE /users/:id(.:format) {:action=>"destroy", :controller=>"users"}
password_resets GET /password_resets(.:format) {:action=>"index", :controller=>"password_resets"}
POST /password_resets(.:format) {:action=>"create", :controller=>"password_resets"}
new_password_reset GET /password_resets/new(.:format) {:action=>"new", :controller=>"password_resets"}
edit_password_reset GET /password_resets/:id/edit(.:format) {:action=>"edit", :controller=>"password_resets"}
password_reset GET /password_resets/:id(.:format) {:action=>"show", :controller=>"password_resets"}
PUT /password_resets/:id(.:format) {:action=>"update", :controller=>"password_resets"}
DELETE /password_resets/:id(.:format) {:action=>"destroy", :controller=>"password_resets"}
password_reset_path /password_resets/:id/edit(.:format) {:controller=>"password_resets", :action=>"edit"}
/documents/:id/locations/create(.:format) {:controller=>"locations", :action=>"create"}
permanent_delete_documents /documents/permanent_delete/:id(.:format) {:controller=>"documents", :action=>"permanently_delete"}
document_authorinfo /documents/:document_id/authorinfo(.:format) {:controller=>"documents", :action=>"authorinfo"}
document_publicationinfo /documents/:document_id/publicationinfo(.:format) {:controller=>"documents", :action=>"publicationinfo"}
document_itemimages /documents/:document_id/images(.:format) {:controller=>"documents", :action=>"itemimages"}
document_locations /documents/:document_id/locations(.:format) {:controller=>"documents", :action=>"locations"}
document_itempeople /documents/:document_id/itempeople(.:format) {:controller=>"documents", :action=>"itempeople"}
document_people_facts_loc /documents/:document_id/people_facts_locations(.:format) {:controller=>"documents", :action=>"people_facts_locations"}
GET /documents/:document_id/locations(.:format) {:action=>"index", :controller=>"locations"}
POST /documents/:document_id/locations(.:format) {:action=>"create", :controller=>"locations"}
new_document_location GET /documents/:document_id/locations/new(.:format) {:action=>"new", :controller=>"locations"}
edit_document_location GET /documents/:document_id/locations/:id/edit(.:format) {:action=>"edit", :controller=>"locations"}
document_location GET /documents/:document_id/locations/:id(.:format) {:action=>"show", :controller=>"locations"}
PUT /documents/:document_id/locations/:id(.:format) {:action=>"update", :controller=>"locations"}
DELETE /documents/:document_id/locations/:id(.:format) {:action=>"destroy", :controller=>"locations"}
document_people GET /documents/:document_id/people(.:format) {:action=>"index", :controller=>"document_people"}
POST /documents/:document_id/people(.:format) {:action=>"create", :controller=>"document_people"}
new_document_person GET /documents/:document_id/people/new(.:format) {:action=>"new", :controller=>"document_people"}
edit_document_person GET /documents/:document_id/people/:id/edit(.:format) {:action=>"edit", :controller=>"document_people"}
document_person GET /documents/:document_id/people/:id(.:format) {:action=>"show", :controller=>"document_people"}
PUT /documents/:document_id/people/:id(.:format) {:action=>"update", :controller=>"document_people"}
DELETE /documents/:document_id/people/:id(.:format) {:action=>"destroy", :controller=>"document_people"}
document_document_facts GET /documents/:document_id/document_facts(.:format) {:action=>"index", :controller=>"document_facts"}
POST /documents/:document_id/document_facts(.:format) {:action=>"create", :controller=>"document_facts"}
new_document_document_fact GET /documents/:document_id/document_facts/new(.:format) {:action=>"new", :controller=>"document_facts"}
edit_document_document_fact GET /documents/:document_id/document_facts/:id/edit(.:format) {:action=>"edit", :controller=>"document_facts"}
document_document_fact GET /documents/:document_id/document_facts/:id(.:format) {:action=>"show", :controller=>"document_facts"}
PUT /documents/:document_id/document_facts/:id(.:format) {:action=>"update", :controller=>"document_facts"}
DELETE /documents/:document_id/document_facts/:id(.:format) {:action=>"destroy", :controller=>"document_facts"}
document_facts POST /documents/:document_id/facts(.:format) {:action=>"create", :controller=>"facts"}
new_document_facts GET /documents/:document_id/facts/new(.:format) {:action=>"new", :controller=>"facts"}
edit_document_facts GET /documents/:document_id/facts/edit(.:format) {:action=>"edit", :controller=>"facts"}
GET /documents/:document_id/facts(.:format) {:action=>"show", :controller=>"facts"}
PUT /documents/:document_id/facts(.:format) {:action=>"update", :controller=>"facts"}
DELETE /documents/:document_id/facts(.:format) {:action=>"destroy", :controller=>"facts"}
document_document_photos GET /documents/:document_id/document_photos(.:format) {:action=>"index", :controller=>"document_photos"}
POST /documents/:document_id/document_photos(.:format) {:action=>"create", :controller=>"document_photos"}
new_document_document_photo GET /documents/:document_id/document_photos/new(.:format) {:action=>"new", :controller=>"document_photos"}
edit_document_document_photo GET /documents/:document_id/document_photos/:id/edit(.:format) {:action=>"edit", :controller=>"document_photos"}
document_document_photo GET /documents/:document_id/document_photos/:id(.:format) {:action=>"show", :controller=>"document_photos"}
PUT /documents/:document_id/document_photos/:id(.:format) {:action=>"update", :controller=>"document_photos"}
DELETE /documents/:document_id/document_photos/:id(.:format) {:action=>"destroy", :controller=>"document_photos"}
documents GET /documents(.:format) {:action=>"index", :controller=>"documents"}
POST /documents(.:format) {:action=>"create", :controller=>"documents"}
new_document GET /documents/new(.:format) {:action=>"new", :controller=>"documents"}
edit_document GET /documents/:id/edit(.:format) {:action=>"edit", :controller=>"documents"}
document GET /documents/:id(.:format) {:action=>"show", :controller=>"documents"}
PUT /documents/:id(.:format) {:action=>"update", :controller=>"documents"}
DELETE /documents/:id(.:format) {:action=>"destroy", :controller=>"documents"}
paypal_cancel /payments/cancel(.:format) {:controller=>"payments", :action=>"paypal_cancel"}
paypal_return /payments/success(.:format) {:controller=>"payments", :action=>"paypal_return"}
paypal_ipn /payments/ipn(.:format) {:controller=>"payments", :action=>"create"}
document_search_home_index GET /home/document_search(.:format) {:action=>"document_search", :controller=>"home"}
simple_location_search_home_index GET /home/simple_location_search(.:format) {:action=>"simple_location_search", :controller=>"home"}
date_search_home_index GET /home/date_search(.:format) {:action=>"date_search", :controller=>"home"}
simple_people_search_home_index GET /home/simple_people_search(.:format) {:action=>"simple_people_search", :controller=>"home"}
simple_organisation_search_home_index GET /home/simple_organisation_search(.:format) {:action=>"simple_organisation_search", :controller=>"home"}
document_filter_home_index GET /home/document_filter(.:format) {:action=>"document_filter", :controller=>"home"}
search_results_home_index GET /home/search_results(.:format) {:action=>"search_results", :controller=>"home"}
POST /home/search_results(.:format) {:action=>"search_results", :controller=>"home"}
home_index GET /home(.:format) {:action=>"index", :controller=>"home"}
POST /home(.:format) {:action=>"create", :controller=>"home"}
new_home GET /home/new(.:format) {:action=>"new", :controller=>"home"}
edit_home GET /home/:id/edit(.:format) {:action=>"edit", :controller=>"home"}
home GET /home/:id(.:format) {:action=>"show", :controller=>"home"}
PUT /home/:id(.:format) {:action=>"update", :controller=>"home"}
DELETE /home/:id(.:format) {:action=>"destroy", :controller=>"home"}
publicationinfo /documents/publicationinfo/:id(.:format) {:controller=>"documents", :action=>"publicationinfo"}
publishinginfo /documents/update/publishinginfo/:id(.:format) {:controller=>"documents", :action=>"publishinginfo"}
remove_image /documents/document_image_remove/:id(.:format) {:controller=>"documents", :action=>"remove_image"}
make_primary_image /documents/make_primary_image/:id(.:format) {:controller=>"documents", :action=>"make_primary_image"}
person_detail /person_detail/:id(.:format) {:controller=>"documents", :action=>"person_detail"}
about /about(.:format) {:action=>"about", :controller=>"pages"}
contact /contact(.:format) {:action=>"contact", :controller=>"pages"}
privacy /privacy(.:format) {:action=>"privacy", :controller=>"pages"}
terms /terms(.:format) {:action=>"terms", :controller=>"pages"}
help /help(.:format) {:action=>"help", :controller=>"pages"}