We often want to style active links in our Rails to improve the users perception of their location in a given website. However, a:active is rarely sufficient when you’ve got sub menus on your site.

I went searching for people who’d already tackled this problem and found the post by ‘jammanbo’ on this page:

http://www.ruby-forum.com/topic/178087

jammanbo’s helper detects if the current path matches another path’s controller and action, returning ‘active’ or ” to use as the link class. While this is useful, there are many times when we want to match to a different level of specificity for links. For example, top level menus in sites I’m working on tend to match a controller, and sub menu entries to the action. Other times, we also want to match the route’s parameters.

Taking this into consideration, I came up with this helper:

This helper returns a string, either ‘active’ or ” depending on if the URI parameter matches. The optional second parameter defines the specificity, either

• :action (default) match both controller and action
• :controller match just controller, or
• :complete matches all parameters in the route (except extra ?param=whatever)

To use it, simply drop it into your ApplicationHelper, then start styling links with:

Have fun!