所以我试图让acts_as_commentable_with_threading gem在我的应用程序中运行。我想允许用户评论特定事件（events / show.html）。我认为我没有正确设置，因为我收到了以下错误。
错误：
显示/Users/user/Sites/new_work/app/views/events/show.html.erb第36行：
First argument in form cannot contain nil or be empty
</div>
<div class="name"></div>
<div id="comments">
<%= form_for @comment do |f| %> <---- it's referring to this line
<div><%= f.hidden_field :event_id, value: @event.id %></div>
<div><%= f.text_field :body, row: 20, placeholder: "Leave a comment" %></div>
<%= f.submit "Post Comment" %>
comments_controller.rb
class CommentsController < ApplicationController
before_filter :load_commentable
def index
@comments = @commentable.current_user.comments
end
def new
@comment = @commentable.current_user.comments.new
end
def create
@comment = @commentable.current_user.comments.new(params[:comment])
if @comment.save
redirect_to @commentable, notice: "Comment created."
else
render :new
end
end
private
def load_commentable
resource, id = request.path.split('/')[1, 2]
@commentable = resource.singularize.classify.constantize.find(id)
end
end
comment.rb snippit only
class Comment < ActiveRecord::Base
attr_accessible :title, :body, :subject
acts_as_nested_set :scope => [:commentable_id, :commentable_type]
validates :body, :presence => true
validates :user, :presence => true
# NOTE: install the acts_as_votable plugin if you
# want user to vote on the quality of comments.
#acts_as_votable
belongs_to :commentable, :polymorphic => true
# NOTE: Comments belong to a user
belongs_to :user
event.rb
class Event < ActiveRecord::Base
attr_accessible :title, :description, :location, :date, :time, :event_date
acts_as_commentable
has_many :comments, as: :commentable
belongs_to :user
after_create :update_event_date
def update_event_date
date = self.date.to_s
time = self.time
hour = Time.parse(time).strftime("%H:%M:%S").to_s
event_date = (date + ' ' + hour).to_time
self.update_attributes(event_date: event_date)
end
end
评论/ form.html.erb
<%= form_for [@commentable, @comment] do |f| %>
<% if @comment.errors.any? %>
<div class="error_messages">
<h3>Please correct the following errors.</h3>
<ul>
<% @comment.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
</ul>
</div>
<% end %>
<div class="field">
<%= f.text_field :body, rows: 10, placeholder: "Leave a comment" %>
</div>
<div class="actions">
<%= f.submit "Post comment", class: "btn" %>
</div>
<% end %>
events_controller.rb
class EventsController < ApplicationController
before_filter :authenticate_user!
def index
@user = current_user
@events = Event.all
end
def new
@event = Event.new
end
# def create
# @event = Event.new(params[:event])
# if @event.save
# redirect_to :action => 'index'
# else
# @events = Event.find(:all)
# render :action => 'new'
# end
# end
def create
@event = current_user.events.new(event_params)
respond_to do |format|
if @event.save
format.html { redirect_to :back, notice: 'Event was successfully created.' }
format.json { render action: 'show', status: :created, location: @event }
format.js
else
format.html { render action: 'new' }
format.json { render json: @event.errors, status: :unprocessable_entity }
format.js
end
end
end
def show
@event = Event.find(params[:id])
end
def edit
@event = Event.find(params[:id])
end
def update
@event = Event.find(params[:id])
if @event.update_attributes(params[:event])
flash[:success] = "Event updated."
redirect_to @event
else
render 'edit'
end
end
def destroy
@event = Event.find(params[:id])
@event.destroy
respond_to do |format|
format.html {redirect_to :back}
format.js
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_event
@event = Event.find(params[:id])
end
的routes.rb
New_app::Application.routes.draw do
# get 'auth/:provider/callback', to: 'sessions#create'
# get 'auth/failure', to: redirect('/')
root to: "home#landing"
devise_for :users, :controllers => {:registrations => "users/registrations",
:sessions => "users/sessions",
:passwords => "users/passwords",
:omniauth_callbacks => "users/omniauth_callbacks"
}
get "welcome", to: "home#welcome", as: 'welcome'
devise_scope :user do
# get "edit/edit_account", :to => "devise/registrations#edit_account", :as => "account_registration"
get 'edit/edit_account' => 'users/registrations#account_registration', as: :edit_account
end
# patch '/users/:id', to: 'users#update', as: 'user'
get 'profile/:id' => "users#show", as: :profile
get 'disconnect' => 'users#disconnect'
resources :users do
resources :questions
end
resources :photos
resources :events do
resources :comments
end
post "/events/add_new_comment" => "events#add_new_comment", :as => "add_new_comment_to_events", :via => [:event]
resources :questions
end
征求评论路线
event_comments GET /events/:event_id/comments(.:format) comments#index
POST /events/:event_id/comments(.:format) comments#create
new_event_comment GET /events/:event_id/comments/new(.:format) comments#new
edit_event_comment GET /events/:event_id/comments/:id/edit(.:format) comments#edit
event_comment GET /events/:event_id/comments/:id(.:format) comments#show
PATCH /events/:event_id/comments/:id(.:format) comments#update
PUT /events/:event_id/comments/:id(.:format) comments#update
DELETE /events/:event_id/comments/:id(.:format) comments#destroy
答案 0 :(得分：1)
在事件控制器的“show”操作中是否定义了@comment？你也可以发布事件控制器代码吗？
仔细检查的一件事是确保呈现show.html.erb视图的操作定义了@comment变量。您似乎收到了消息，因为
中的@comment变量<%= form_for @comment do |f| %>
渲染视图时当前为nil。
在事件控制器的“show”操作中，尝试通过添加：
来设置@comment变量@comment = @event.comments.new
编辑2：确保您已设置routes.rb文件以处理有关事件的注释，因此假设您使用RESTful路由，请在routes.rb中使用以下内容。如果您可以发布路线文件也很有帮助。
resources :events do
resources :comments
end
答案 1 :(得分：0)
错误发生在 app / views / events / show.html.erb 上，这意味着您的事件控制器的显示操作缺失了@comment变量
def show
@event = Event.find(params[:id])
@comment = ....what ever you need to pull in the comments....
end