Semantic navigation; a semantic way to build beautifully simple navigation structures in Rails views or configuration.
I initially wrote Navigasmic over 3 years ago, primarily because there weren't any navigation helpers at the time. It was a project that I'd cobbled together from things that I'd done in a project I was working on at the time and it wasn't very elegant.
Since then there's been several other navigation gems created, and some of them are really awesome. For some reason though I've always found myself back with Navigasmic -- and it doesn't seem to do with the fact that I wrote it.
Honestly, I all but abandoned it for over 2 years, only accepting pull requests, which was a pretty crappy thing for me to do. So since I still use it, and like it, it seemed about damn time to give it some much needed updating and love. And to appologize for being a bad open source maintainer.
Most of the navigation styles I've done over the years pretty much boil down to this idea: Use simple markup, and do the rest with CSS (and Javascript if you need it). Because of that the default markup is beautifully simple (UL and LI tags).
Ok, so navigation is easy right? Until you start managing active, disabled, and hidden states, and more if you may need them. This can quickly become a mess, and all too often it just stays in the views with whatever logic tossed on top of it as people go. I've seen it too many times, and I wanted to do something about it.
These where the core goals:
- be simple
- be easily customizable
- handle active/highlighted states
- handle disabled states
- be pleasant to use
- uses less code to create than it generates
And working with gvarela at the time, we wrote a DSL that met those requirements:
semantic_navigation :primary do |n|
n.group 'Blog' do
n.item 'Articles', '/blog/posts', highlights_on: '/my_awesome_blog'
n.item 'Links', '/blog/links', disabled_if: proc { !logged_in? }
n.item 'My Portfolio' # auto links to the my_portfolio_path if it exists
end
end
Since we wanted something that allowed for customization we ended up using the Builder Pattern -- the way Rails uses form builders basically. There are some builders that are provided, and these builders can be configured, extended or replaced if you need more custom markup -- there's more on how to do that stuff below.
Include the gem in your Gemfile and bundle to install the gem. (Navigasmic requires Ruby 1.9+)
gem 'navigasmic'
You can also get the initializer by running the install generator.
rails generate navigasmic:install
Navigasmic allows you to define navigation in two ways. The first is directly in your views (in a partial, or layout for instance), and the second is via a global configuration (similar to how simple-navigation works).
config.semantic_navigation :primary do |n|
n.group 'Blog', class: 'blog' do
n.item 'Articles', controller: '/blog/posts'
n.item 'Links', controller: '/blog/links'
end
n.group 'Info' do
n.item 'Me', '/about', title: 'The Awesomeness That Is'
n.item 'My Portfolio'
end
end
The semantic_navigation
method in Navigasmic provides a single name for defining and rendering navigation. You can
use this method in your layouts, views, and partials to render navigation structures that you've defined in the
initializer.
<%= semantic_navigation :primary, class: 'my-navigation' %>
While it's nice to be able to define navigation in the initializer, it's also nice to be able to prototype out some
navigation in the views directly. You can do this by simply passing a block to the semantic_navigation
helper. By
passing it a block you're able to define the navigation structure easily and quickly.
ERB
<%= semantic_navigation :primary, builder: Navigasmic::Builder::ListBuilder, class: 'my-navigation' do |n| %>
<% n.group 'Blog', class: 'blog' do %>
<li>Custom Node</li>
<% n.item 'Articles', controller: '/blog/posts' %>
<% n.item 'Links', controller: '/blog/links' %>
<% end %>
<% n.group 'Info' do
n.item 'Me', '/about', title: 'The Awesomeness That Is'
n.item 'My Portfolio'
end %>
<% end %>
HAML
= semantic_navigation :primary, config: :bootstrap, class: 'my-navigation' do |n|
- n.group 'Blog', class: 'blog' do
%li Custom Node
- n.item 'Articles', controller: '/blog/posts'
- n.item 'Links', controller: '/blog/links'
- n.group 'Info' do
- n.item 'Me', '/about', title: 'The Awesomeness That Is'
- n.item 'My Portfolio'
If you ran the install generator you should have a navigasmic.rb
file in your initializers. This file has several
examples and some more documentation. It can be used to define navigation structures as well as create named
configurations for each builder.
When you invoke the semantic_navigation
method you can provide which builder you want to use, and the named
configuration for that builder. By defining these builder specific configurations you'll be able to render navigation
differently in different parts of your site using the same builder. This allows for the greatest flexibility.
Twitter Bootstrap is pretty awesome, so it's worth supporting. There's a configuration that's provided in the initializer that allows for nice bootstrap support. It handles nav-pills, nav-tabs, and the navbar structure.
There's several options that you can pass to the item
method that dictate the state of a given navigation item. You
can tell it what to highlight on, if it's disabled and when, and if it should be hidden entirely.
All of the options allow for passing a proc. In the examples below procs are used on anything that needs to happen within the view scope. This is especially useful when you define the navigation structure in an initializer. If you want to check if a user is logged in, those things need to happen within the view scope, so if you're defining your navigation in a view scope you don't need to use a proc, but if you're using the initializer you will.
You can pass links to the item
method in a few ways. You can just provide a controller (and/or action) in the
options, you can pass a first argument, or you can explicitly call out what the link options are. Here are some
examples:
n.item 'Articles', controller: '/blog/posts', class: 'featured'
n.item 'Articles', controller: '/blog/posts', action: 'index', class: 'featured'
n.item 'Articles', '/blog/posts', class: 'featured'
n.item 'Articles', {controller: '/blog/posts'}, class: 'featured'
n.item 'Articles', class: 'featured', link: {controller: '/blog/posts'}
You can take this much further by matching specific url options. Here's some examples that would match to specific blog posts (they will also only highlight on the given record):
n.item 'Article', {controller: '/blog/posts', action: 'show', id: '42'},
n.item 'Article', class: 'featured', link: {controller: '/blog/posts', action: 'show', id: '42'}
Note that we're passing a string for the posts id.. That's because when the param comes in and is compared against the link options you provided, the types need to match.
If you don't provide a link, Navigasmic attempts to find a path helper from the label. In the following example we
only provide the label, but if I've defined a route (eg. match '/portfolio' => 'portfolio#index', as: 'my_portfolio'
)
it will automatically use the `my_porfolio_path' path helper.
n.item 'My Portfolio' # Yeah auto link!
Highlight rules allows for passing an array containing any of/or a Boolean, String, Regexp, Hash or Proc. The following examples will highlight:
n.item 'On the /my_thoughts path, and on Mondays', '/blog/posts', highlights_on: ['/my_thoughts', proc{ Time.now.wday == 1}]
n.item 'On any action in BlogController', highlights_on: [{controller: 'blog'}]
n.item 'On any path beginning with "my_"', highlights_on: /^\/my_/
n.item 'Only on "/my_thoughts"', highlights_on: '/my_thoughts'
n.item 'When the highlight param is set', highlights_on: proc{ params[:highlight].present? }
Disable rules allow for you to pass a Boolean or Proc. The following examples will be disabled:
n.item 'On Tuesdays, and when not logged in', disabled_if: proc{ Time.now.wday == 2 || !logged_in? }
n.item 'Never', disabled_if: false
n.item 'Always', disabled_if: true
Hide rules allow for you to pass a Boolean or Proc. The following examples will be hidden:
n.group 'On Tuesdays, and when not logged in', hidden_unless: proc{ Time.now.wday != 2 && logged_in? } do
n.item 'When not logged in', hidden_unless: proc{ logged_in? }
n.item 'Never', hidden_unless: false
n.item 'Always', hidden_unless: true
end
Navigasmic comes with a few builders by default. Here's a breakdown of what's available, and what each one does.
- Navigasmic::Builder::ListBuilder
Builds an HTML structure of UL and LI tags. Useful for most navigation structured rendered in markup. - Navigasmic::Builder::MapBuilder
Builds an XML structure that use the Sitemaps XML format - Navigasmic::Builder::CrumbBuilder (incomplete)
Builds an HTML structure of A tags based on the first highlighted item it finds and up. Useful for breadcrumbs.
The ListBuilder is the default builder (unless otherwise specified in the initializer). It builds a UL/LI structure that's pretty easy to style and work with.
excluded_keys
- Array: Allows specifying keys that are ignored in options (you may want to ignore keys used by other builders.) Default:[:map]
wrapper_tag
- Symbol (or String): Tag used for the top level element. Default::ul
group_tag
- Symbol (or String): Tag used for wrapping groups. Default::ul
item_tag
- Symbol (or String): Tag used for wrapping specific items. Default::li
wrapper_class
- String: The classname that will be applied to the top level element. Default:'semantic-navigation'
item_class
- String: The classname that will be applied to any item by default. Default:nil
has_nested_class
- String: The classname that will be applied to any group (or item with nested items). Default:'with-group'
is_nested_class
- String: The classname that will be applied to any nested items (within a group or item). Default:'with-group'
disabled_class
- String: The classname that will be applied to disabled items. Default:'disabled'
highlighted_class
- String: The classname that will be applied to items that should be highlighted. Default:'active'
label_generator
- Proc: Called when inserting labels into items or groups. Default:proc{ |label, options, has_link, has_nested| "<span>#{label}</span>" }
link_generator
- Proc: Called when generating links. Default:proc{ |label, link, link_options, is_nested| link_to(label, link, options.delete(:link_html)) }
The MapBuilder is used for generate XML sitemaps that follow the protocol laid out by the Sitemaps XML format.
excluded_keys
- Array: Allows specifying keys that are ignored in options (you may want to ignore keys used by other builders.) Default:[]
option_namespace
- Symbol (or String): Option key that holds the map specific options (eg. :changefreq, :priority, :lastmod etc.) Default::map
wrapper_tag
- Symbol (or String): Tag used for the top level element. Default::urlset
item_tag
- Symbol (or String): Tag used for wrapping specific items (groups are not used in this builder.) Default::url
A simple example of using the MapBuilder -- create a [action].xml.builder
view, and add the following:
xml.instruct!
xml << semantic_navigation(:primary, builder: Navigasmic::Builder::MapBuilder)
Licensed under the MIT License
Copyright 2012 Jeremy Jackson