Discussion on: Rails Layouts

[Andrew Brown 🇨🇦]

If you want to set a controller to utilize a specific layout for all its actions
Notice its

layout 'admin'

instead of

layout :admin

since passing a symbol does something different.

class UsersController < ApplicationController
  layout 'admin'
end

So lets say you wanted to only apply layout to specific actions maybe you think you could do this because you can do this with before_actions:

class UsersController < ApplicationController
  layout 'form', only: %w{new create edit update}
end

This, however, doesn't work, so how do you get conditional layouts? This is where symbol comes in, its actually telling it to call a function in the controller to handle the logic

class UsersController < ApplicationController
  layout :guess


  def guess
    case action_name
    when "new", "create", "edit", "update"
      "form"
    else
      "application"
    end
  end

end

Also you noticed when I did this:

%w{new create edit update}

This is a clever shorthand for arrays which will split on the space so its the same as:

['new', 'create' , 'edit' , 'update']

I keep thinking about making an open-source Rails course, can you tell?