Simplify engine to register assets

Author: zorab47

lib/active_admin/sortable_tree/engine.rb

@@ -1,32 +1,20 @@
-require 'activeadmin'
-require "rubygems"
+require "activeadmin"
 
 module ActiveAdmin
   module SortableTree
     class Engine < ::Rails::Engine
-      engine_name 'active_admin-sortable_tree'
+      engine_name "active_admin-sortable_tree"
 
-
-      def jquery_ui_six?
-        Gem::Version.new(Jquery::Ui::Rails::VERSION) >= Gem::Version.new("6.0.0")
-      end
-
-      def sortable_js
-        if jquery_ui_six?
+      initializer "active_admin-sortable_tree.precompile", group: :all do |app|
+        app.config.assets.precompile += [
+          "active_admin/sortable.css",
           "active_admin/sortable.js"
-        else
-          "active_admin/sortable_ui5.js"
-        end
-      end
-
-      initializer "Rails precompile hook", group: :all do |app|
-        app.config.assets.precompile += [ "active_admin/sortable.css",
-                                          sortable_js ]
+        ]
       end
 
-      initializer "add assets" do
+      initializer "active_admin-sortable_tree.register_assets" do
         ActiveAdmin.application.register_stylesheet "active_admin/sortable.css"
-        ActiveAdmin.application.register_javascript sortable_js
+        ActiveAdmin.application.register_javascript "active_admin/sortable.js"
       end
     end
   end