undefined local variable or method `new_comment` - ruby-on-rails

Question

NameError in Comments#create
Showing /comments/_form.html.erb
where line #1 raised:
undefined local variable or method new_comment for #<#:0x007fb9760eb640>
<%= form_for new_comment, url: send(create_url, new_comment.commentable) do |f| %>
new_comment is being called by:
activities/index.html.erb
<%= render "comments/form", new_comment: Comment.new(commentable_id: activity.id, commentable_type: activity.class.model_name), create_url: :activity_comments_path %>
comment.rb
class Comment < ActiveRecord::Base
after_save :create_notification #ERROR OCCURRED WHEN I INTRODUCED THIS LINE AND
validates :activity, presence: true #THIS LINE
validates :user, presence: true
has_many :notifications
belongs_to :commentable, polymorphic: true
belongs_to :user
belongs_to :activity
private
def create_notification
Notification.create(
activity_id: self.activity_id,
user_id: self.user_id,
comment_id: self.id,
read: false
)
end
end
notification.rb
class Notification < ActiveRecord::Base
belongs_to :activity
belongs_to :comment
belongs_to :user
end
activity.rb
class Activity < ActiveRecord::Base
self.per_page = 20
has_many :notifications
belongs_to :user
has_many :comments, as: :commentable
belongs_to :trackable, polymorphic: true
def conceal
trackable.conceal
end
def page_number
(index / per_page.to_f).ceil
end
private
def index
Activity.order(created_at: :desc).index self
end
end
routes.rb
resources :activities do
resources :comments
resources :notifications
member do
post :like
post :notifications
end
end
Any ideas on what maybe the cause? This error is coming off of the awesome answer here: How to make a path to a paginated url?
Thank you!
UPDATE
class CommentsController < ApplicationController
before_action :load_commentable
before_action :set_comment, only: [:show, :edit, :update, :destroy, :like]
before_action :logged_in_user, only: [:create, :destroy]
def index
#comments = #commentable.comments
end
def new
#comment = #commentable.comments.new
end
def create
#comment = #commentable.comments.new(comment_params)
if #comment.save
redirect_to #commentable, notice: "comment created."
else
render :new
end
end
def edit
#comment = current_user.comments.find(params[:id])
end
def update
#comment = current_user.comments.find(params[:id])
if #comment.update_attributes(comment_params)
redirect_to #commentable, notice: "Comment was updated."
else
render :edit
end
end
def destroy
#comment = current_user.comments.find(params[:id])
#comment.destroy
redirect_to #commentable, notice: "comment destroyed."
end
def like
#comment = Comment.find(params[:id])
#comment_like = current_user.comment_likes.build(comment: #comment)
if #comment_like.save
#comment.increment!(:likes)
flash[:success] = 'Thanks for liking!'
else
flash[:error] = 'Two many likes'
end
redirect_to(:back)
end
private
def set_comment
#comment = Comment.find(params[:id])
end
def load_commentable
resource, id = request.path.split('/')[1, 2]
#commentable = resource.singularize.classify.constantize.find(id)
end
def comment_params
params[:comment][:user_id] = current_user.id
params.require(:comment).permit(:content, :commentable, :user_id, :like)
end
end
notifications_controller
class NotificationsController < ApplicationController
def index
#notifications = current_user.notifications
#notifications.each do |notification|
notification.update_attribute(:read, true)
end
end
def destroy
#notification = Notification.find(params[:id])
#notification.destroy
redirect_to :back
end
end
activities_controller
class ActivitiesController < ApplicationController
def index
#activities = Activity.order("created_at desc").paginate(:page => params[:page])
end
def show
redirect_to(:back)
end
def like
#activity = Activity.find(params[:id])
#activity_like = current_user.activity_likes.build(activity: #activity)
if #activity_like.save
#activity.increment!(:likes)
flash[:success] = 'Thanks for liking!'
else
flash[:error] = 'Two many likes'
end
redirect_to(:back)
end
end

Answer 1

It should be <%= form_for comment do |f| %> not new comment since comment is the element in your database