Question

I’ve been using the same tactics in the Mobile Devices railscast to provide an alternate layout for my site in a mobile browser.

When a mobile browser is detected, the request.format is set to :mobile, which I’ve defined as a mime type.
I have created a new layout for mobile devices.
If I provide a mobile view (e.g. show.mobile.haml), both the mobile view and layout are used on mobile devices, and everything works great.

The problem is, I don’t want to create entirely new views, it’s just the layout I want to change. If I don’t create an appropriately named view, the mobile layout is never used. So as-is I can only manage to change both or neither on mobile devices.

What am I missing here? How can I get rails to swap out just the layout when I’ve got a mobile user?

Answer 1

Assuming you have added the mobile_device? method from railscasts then simply add the following to application_controller.rb:

  layout :which_layout
  def which_layout
    mobile_device? ? 'mobile' : 'application'
  end

Be sure to create the mobile.html.erb file in app/views/layouts

Since you want to render the same view, don’t worry about setting the request.format.