"undefined method `title' for nil:NilClass" Rails Guides Tutorial

you have made your methods private. Remember where you put private keyword. all the methods below that, will become private, define your methods like this. private methods in end of the controller :

class PostsController < ApplicationController

def new 
  @post = Post.new
end

def index
  @posts = Post.all
end

def create
@post = Post.new(params[:post].permit(:title, :text))

  if @post.save
    redirect_to @post
  else
    render 'new'
  end
end

def show
  @post = Post.find(params[:id])
end

def edit
  @post = Post.find(params[:id])
end

def update
  @post = Post.find(params[:id])

  if @post.update(params[:post].permit(:title, :text))
    redirect_to @post
  else 
    render 'edit'
  end
end

def destroy
  @post = Post.find(params[:id])
  @post.destroy

  redirect_to posts_path
end



private
 def post_params
  params.require(:post).permit(:title, :text)
 end

end

Hope it will help. Thanks

I met the same problem as you when following the tutorial. And I checked my codes again then found the reason. In the posts_controller.rb file, you cannot put the private method in the middle of the codes, that means all the methods below (such as show, edit) will be private. Instead, put the private method at the bottom like this:

class PostsController < ApplicationController
    def new
    end
    def index
        @posts = Post.all
    end
    def create
        @post = Post.new(post_params)
        @post.save
        redirect_to @post
    end
    def show
        @post = Post.find(params[:id])
    end
    private
        def post_params
            params.require(:post).permit(:title, :text)
        end
end

Hope to solve your problem.