class ActiveAdmin::Scope

# => Scope with name 'Published' using a block to scope
Scope.new('Published') { |articles| articles.where(:published => true) }

# => Scope with name 'Published' and scope method :public
Scope.new('Published', :public)

# => Scope with name 'Published' and scope method :published
Scope.new(:published)

Examples:

Create a Scope

def initialize(name, method = nil, &block)
  @name = name.to_s.titleize
  @scope_method = method
  # Scope ':all' means no scoping
  @scope_method ||= name.to_sym unless name.to_sym == :all
  @id = @name.gsub(' ', '').underscore
  if block_given?
    @scope_method = nil
    @scope_block = block
  end
end