Add possibility to sort by group

[sasselin]

Example:

Category #1

• Element 1 to sort
• Element 2 to sort

Category #2

• Element 1 to sort
• Element 2 to sort

[ouelletv]

Here is a possible solution i came up with :

In nestable_helper.rb

module RailsAdmin
  module NestableHelper
    RailsAdmin::ApplicationHelper.class_eval do
      def menu_for(parent, abstract_model = nil, object = nil, only_icon = false) # perf matters here (no action view trickery)
        actions = actions(parent, abstract_model, object).select { |a| a.http_methods.include?(:get) }
        actions.collect do |action|
          wording = wording_for(:menu, action)
          %(
            <li title="#{wording if only_icon}" rel="#{'tooltip' if only_icon}" class="icon #{action.key}_#{parent}_link #{'active' if current_action?(action)}">
              <a class="#{action.pjax? ? 'pjax' : ''}" href="#{url_for(action: action.action_name, controller: 'rails_admin/main', model_name: abstract_model.try(:to_param), id: (object.try(:persisted?) && object.try(:id) || nil), query: (action.key == :nestable) ? params[:query] : nil)}">
                <i class="#{action.link_icon}"></i>
                <span#{only_icon ? " style='display:none'" : ''}>#{wording}</span>
              </a>
            </li>
          )
        end.join.html_safe
      end
    end
  end
end

This little snippet allows you to pass along the query param in the url to the orderable list view. Then, you could just use the built in rails_admin filter to scope your list and order the filtered results.

I was thinking about doing a merge request about this. Tell me what you guys think.