new.html.erb

<%= notice %>
<%= render 'form' %>

posts_controller.rb

class PostsController < ApplicationController
  
  # GET /posts
  # posts
  def index
    @posts = Post.all
     respond_to do |format|
        format.html # index.html.erb
        format.json { render json: @posts }
      end
  end
  
  # GET /posts/new
  # new_post
  def new
    @post = Post.new
    respond_to do |format|
      format.html
    end
  end
  
  # POST /posts
  def create
    @post = Post.new(params[:post])
    respond_to do |format|
      if @post.save
        format.html { redirect_to @post, notice: 'Post succesfully saved' }
      else
        format.html { render action: "new", notice: 'Error saving the post' }
      end
    end
  end
  
  # GET /posts/1
  # post
  def show
    @post = Post.find(params[:id])
    respond_to do |format|
      format.html
    end
  end
  
  # GET /posts/1/edit
  # edit_post
  def edit
    @post = Post.find(params[:id])
    respond_to do |format|
      format.html
      format.json
    end
  end
  
  # PUT /posts/1
  def update
    @post = Post.find(params[:id])
    respond_to do |format|
      if @post.update_attributes(params[:post])   
        format.html { redirect_to @post, notice: 'Post successfully updated' }
      else
        format.html { render action: "edit", notice: 'Error saving the post' }
      end
    end
  end
  
end