activity_sequence

activities_helper.rb

# config/initializers/activity_order.rb
ACTIVITIES = [PersonalValues, PersonActions, SomeOther]

# config/initializer/array.rb
class Array
  def relative_index(item, idx)
    self[index(item) + idx]
  end
  
  def next(item)
    relative_index(item, 1)
  end

  def prev(item)
    relative_index(item, -1)
  end
end

#helper file or whatever
def next_activity(klass)
  get_path(ACTIVITIES.next(klass))
end

def prev_activity(klass)
  get_path(ACTIVITIES.prev(klass)
end

def get_path(model)
 send(model.to_s.underscore.pluralize + "path")
end