Navy support rendering for horizontal, multi-level navigation bars. Sections are dynamic and can depend on user permissions etc.

Some of the features are:

• A simple but powerful DSL to describe the navigation structure
• Subnavigations can be previewed by clicking an expand arrow
• Sections that don't fit into the navigation bar are automatically moved into a dropdown

The gem provides the DSL to specify the navigation structure as well as a renderer that outputs appropriate HTML.

To style it, we provide a sample .sass stylesheet you have to copy and include into your stylesheet, as well as adapt to your design.

The javascript functionality is provided in navy.js that you have to copy and include in your application.

The gem should be considered in an alpha state.

Styles are not very flexible yet, it might be hard to adapt them to your needs.

The standard styles do not work well with old browsers (e.g. IE 8).

The JavaScript features are somewhat dependent on the CSS (to determine when sections will be collapsed). In particular, you have to make sure that the dropdown arrow floats correctly right of the navigation sections.

Some assets have to be copied manually, there is no generator yet.

Put this into your Gemfile:

gem 'makandra-navy', :require => 'navy'

Copy stylesheets, javascripts and (perhaps) cucumber steps from /assets into your project.

Navigation structure is defined with a class like this (somewhere in your load path):

class Navigation
  include Navy::Description

  navigation :main do

    section :dashboard, "Dashboard", root_path

    if current_user.admin?
      section :admin, 'Admin' do
        section :admin_users, "Users", admin_users_path

        if current_user.may_admin_projects?
          section :admin_projects, "Projects", admin_projects_path
        end
      end
    end
  end

  navigation :footer do
    section :terms, "Terms and Conditions", terms_and_conditions_path
    section :imprint, "Imprint", imprint_path
  end

  navigation :user do |user|
    section :settings, "Settings", user_settings_path(user)
  end

end

This is all evaluated in your view context, so helpers will work.

To actually render a navigation, do this in your view:

<%= render_navigation Navigation.main, :collapse => true %>

<%= render_navigation Navigation.footer %>

<%= render_navigation Navigation.user(current_user) %>

The :collapse => true option enables the automatic moving of navigation sections into a dropdown if they do not fit.

There are some cucumber steps in /assets.

The most important one is:

When I open the "Admin" section

To open submenu entries, use

When I open the "Admin > Projects" section

Tobias Kraze, Henning Koch