TabsOnRails

TabsOnRails is a simple Rails plugin for creating and managing Tabs. It provides helpers for creating tabs with a flexible interface.

Rails Installation

As a Gem

This is the preferred way to install TabsOnRails and the best way if you want install a stable version.

$ gem install weppos-tabs_on_rails --source http://gems.github.com

You can specify the GEM dependency in your application environment.rb file:

Rails::Initializer.run do |config|

  # other configurations

  config.gem "weppos-tabs_on_rails", :lib => "tabs_on_rails", :source => "http://gems.github.com"
end

As a Plugin

This is the preferred way if you want to live on the edge and install a development version.

$ script/plugin install git://github.com/weppos/tabs_on_rails.git

Quick Start

In your template use the tabs_tag helper to create your tab.

<% tabs_tag do |tab| %>
  <%= tab.home      'Homepage', root_path %>
  <%= tab.dashboard 'Dashboard', dashboard_path %>
  <%= tab.account   'Account', account_path %>
<% end %>

The example above produces the following HTML output.

<ul>
  <li><a href="/">Homepage</a></li>
  <li><a href="/dashboard">Dashboard</a></li>
  <li><a href="/account">Account</a></li>
</ul>

The usage is similar to the Rails route file. You create named tabs with the syntax tab.name_of_tab.

The name you use creating a tab is the same you’re going to refer to in your controller when you want to mark a tab as the current tab.

class DashboardController < ApplicationController
  set_tab :dashboard
end

Now, if the action belongs to DashboardController, the template will automatically render the following HTML code.

<ul>
  <li><a href="/">Homepage</a></li>
  <li><span>Dashboard</span></li>
  <li><a href="/account">Account</a></li>
</ul>

Use the current_tab helper method if you need to access the value of current tab in your controller or template.

class DashboardController < ApplicationController
  set_tab :dashboard
end

# In your view
<p>The name of current tab is <%= current_tab %>.</p>

Restricting set_tab scope

The set_tab method understands all options you are used to pass to a Rails controller filter. In fact, behind the scenes this method uses a before_filter to store the tab in the @tab_stack variable.

Taking advantage of Rails filter options, you can restrict a tab to a selected group of actions in the same controller.

class PostsController < ApplicationController
  set_tab :admin
  set_tab :posts, :only => [ :index, :show ]
end

class ApplicationController < ActionController::Base
  set_tab :admin, :if => :admin_controller?

  def admin_controller?
    self.class.name =~ /^Admin(::|Controller)/
  end
end

Using Namescopes to create Multiple Tabs

Namescopes enable you to create and manage tabs in parallels. The best way to demonstrate namescope usage is using an example.

Let’s assume your application provide a first level navigation menu with 3 elements: :home, :dashboard, :projects. The relationship between your tabs and your controllers is 1:1 so you should end up with the following source code.

class HomeController
  set_tab :home
end

class DashboardController
  set_tab :dashboard
end

class ProjectsController
  set_tab :projects

  def first; end
  def second; end
  def third; end
end

The project controller contains 3 actions and you might want to create a second-level navigation menu. This menu should reflect the navigation status of the user in the project page.

Without namespaces, you wouldn’t be able to accomplish this task because you already set the current tab value to :project. You need to create a parallel navigation menu and uniquely identify it with a custom namescope. Let’s call it :navigation.

class ProjectsController
  set_tab :projects

  # Create an other tab navigation level
  set_tab :first, :navigation, :only => %(first)
  set_tab :second, :navigation, :only => %(second)
  set_tab :third, :navigation, :only => %(third)

  def first; end
  def second; end
  def third; end
end

Voilà! That’s all you need to do. And you can create an unlimited number of namescope as long as you use an unique name to identify them.

The default namescope is called :default. Passing :default as namescope name is the same as don’t using any namescope at all. The following lines are equivalent.

# The following 
set_tab :projects
set_tab :projects, :default

Rendering Tabs with Namescopes

To swith namescope in your template, just pass the :namescope option to the tabs_tag helper method.

<% tabs_tag do |tab| %>
  <%= tab.home      'Homepage', root_path %>
  <%= tab.dashboard 'Dashboard', dashboard_path %>
  <%= tab.projects  'Projects', projects_path %>
<% end %>

<% tabs_tag :namescope => :navigation do |tab| %>
  <%= tab.first   'First', first_project_path %>
  <%= tab.second  'Second', second_project_path %>
  <%= tab.third   'Account', third_project_path %>
<% end %>

Namescope scope

As a bonus feature, the namescope name does need to be unique within current request scope, not necessarily across the entire application.

Back to the previous example, you can reuse the same namescope in the other controllers. In this way, you can reuse your templates as well.

class HomeController
  set_tab :home
end

class DashboardController
  set_tab :dashboard

  set_tab :index,  :navigation, :only => %(index)
  set_tab :common, :navigation, :only => %(foo bar)

  # ...
end

class ProjectsController
  set_tab :projects

  set_tab :first,  :navigation, :only => %(first)
  set_tab :second, :navigation, :only => %(second)
  set_tab :third,  :navigation, :only => %(third)

  # ...
end

Tab Builders

The Builder is responsible for creating the tabs HTML code. This library is bundled with two Builders:

Tabs::Builder: this is the abstract interface for any custom builder.
Tabs::TabsBuilder: this is the default builder.

Understanding the Builder

Builders act as formatters. A Builder incapsulates all the logic behind the tab creation including the code required to toggle tabs status.

When the tabs_tag helper is called, it creates a new Tabs instance with selected Builder. If you don’t provide a custom builder, then Tabs::TabsBuilder is used by default.

Creating a custom Builder

All builders must extend the base Tabs::Builder class and implement at least the tab_for method. Additional overridable methods include:

open_tabs: the method called before the tab set
close_tabs: the method called after the tab set
tab_for: the method called to create a single tab item

The following example creates a custom tab builder called MainTabBuilder.

class MenuTabBuilder < TabsOnRails::Tabs::Builder
  def tab_for(tab, name, options, item_options = {})
    item_options[:class] = (current_tab?(tab) ? 'active' : '')
    @context.content_tag(:li, item_options) do
      @context.link_to(name, options)
    end
  end
end

Using a custom Builder

In your view, simply pass the builder class to the tabs_tag method.

<% tabs_tag(:builder => MenuTabBuilder) do |tab| %>
  <%= tab.home        'Homepage', root_path %>
  <%= tab.dashboard,  'Dashboard', dashboard_path %>
  <%= tab.account     'Account', account_path, :style => 'float: right;' %>
<% end %>

This is the final result.

<ul>
  <li class=""><a href="/">Homepage</a></li>
  <li class="active"><a href="/dashboard">Dashboard</a></li>
  <li class="" style="float: right;"><a href="/account">Account</a></li>
</ul>

Documentation

The library is still under development and this README file might not be contain the latest changes. For the full documentation, development roadmap and more information please visit the project page.

Credits

Author: Simone Carletti <[email protected]>