class ActiveAdmin::ResourceDSL

action.
You can treat everything within the block as a standard Rails controller

the named route (comments_admin_post_path) /admin/posts/:id/comments
Will create a new controller action comments and will hook it up to

end
end
@comments = @post.comments
@post = Post.find(params[:id])
member_action :comments do
ActiveAdmin.register Post do

For example:

block.
action and the route directly from your ActiveAdmin registration
Member Actions give you the functionality of defining both the

def action(set, name, options = {}, &block)
  warn "Warning: method `#{name}` already defined in #{controller.name}" if controller.method_defined?(name)
  set << ControllerAction.new(name, options)
  title = options.delete(:title)
  controller do
    before_action(only: [name]) { @page_title = title } if title
    define_method(name, &block || Proc.new {})
  end
end