Rails create action renders as Javascript but doesn't show up on page

Question

I'm building a menu of categories that can be updated using :remote => true in Rails without reloading the page.

My new action successfully renders as javascript and the changes show up on the page however my create action seems to render successfully but doesn't show up on the page. I can see the changes when I reload the page so I know the create action is working. It's just that the javascript doesn't seem to render the page properly. However, if I look at the response of the POST request in Firebug, I can see the intended changes.

Please help. I've spent hours on StackOverflow already trying to find a solution.

My Categories controller

class CategoriesController < ApplicationController

  def new
    @category = Category.new()
  end

  def create
    @category = Category.new(category_params)

    if @category.save
      redirect_to(:controller => 'apps', :action => 'index')
    else
      render('new')
    end

    @categories = Category.where(:parent_id => nil)
  end

  def update
    @category.update_attributes(category_params)
  end

  private

  def category_params
    params.require(:categories).permit(:name, :parent_id)
  end
end

My Apps Controller

class AppsController < ApplicationController
  def index
    @category = nil

    @categories = Category.where(:parent_id => nil)

    @apps = App.all

    respond_to do |format|
      format.html
      format.json
      format.js
    end
  end

  def new
    @app = App.new()
  end

  def create
    @app = App.new(params[:id])

    if @app.save
      redirect_to(:action => 'index')
    else
      render('new')
    end
  end

  private

    def apps_params
      params.require(:apps).permit(:name, :category, :image)
    end
end

The Create form (partial)

<%= simple_form_for :categories, remote: true,
                    :url => url_for(:action => 'create', :controller => 'categories'),
                    :method => 'post' do |f|   %>
    <%= f.input  :name                      %>
<% end %>

Create.js.erb

$('#categories-list').html("<%= j (render 'catList') %>");
$('#category-form').slideUp(350);

_catList.html.erb

<li class="pure-menu-heading">Categories</li>
<% @categories.each do |cat| %>
    <li class="pure-menu-item"><a href="#" class="pure-menu-link"><span class="email-label-personal"></span><%= cat.name %></a></li>
<% end %>

Answer 1

Solved!

I found some guys to help me on another forum.

All I had to do was remove redirect_to(:controller => 'apps', :action => 'index') in the categories controller