[Bug] Fix manual sorting (#723)

* Change condition to pageSize and total instead of needsPaging

* Readd line

* Paging also needs an update for drag and drop single elements

public/js/pimcore/object/tree.js

@@ -362,7 +362,7 @@ pimcore.registerNS("pimcore.object.tree");
          }
 
          // dropping objects not allowed if the tree/folder is paginated and sort by index (manual indexes) is enabled
-         if(((newParent.needsPaging) || (newParent.childNodes.length > pimcore.settings['object_tree_paging_limit'])) && (newParent.data.sortBy == "index")){
+         if(((!newParent.pagingData.canSortManually) || (newParent.childNodes.length > pimcore.settings['object_tree_paging_limit'])) && (newParent.data.sortBy == "index")){
              pimcore.helpers.showNotification(t("error"), t("element_cannot_be_moved_because_target_is_paginated"), "error");
              return false;
          }
@@ -1218,7 +1218,7 @@ pimcore.registerNS("pimcore.object.tree");
          if (currentSortMethod != sortBy && sortBy == "index") {
 
              // Do not allow sort by index(Manual Indexes) for a paginated tree/folder
-             if(record.needsPaging) {
+             if(!record.pagingData.canSortManually) {
                  Ext.MessageBox.alert(
                      t("error"),
                      t("error_object_change_children_sort_to_index"));

public/js/pimcore/overrides.js

@@ -404,7 +404,8 @@ Ext.define('pimcore.data.PagingTreeStore', {
             node.pagingData = {
                 total: data.total,
                 offset: data.offset,
-                limit: data.limit
+                limit: data.limit,
+                canSortManually: data.total < data.limit
             }
 
             me.superclass.onProxyLoad.call(this, operation);