diff --git a/ground/controllers/JsonController.php b/ground/controllers/JsonController.php
index 416a624..93c4794 100644
--- a/ground/controllers/JsonController.php
+++ b/ground/controllers/JsonController.php
@@ -15,8 +15,8 @@ class JsonController extends Controller
         $categories = $categories->getAll();
         
         foreach ($points as &$point) {
-            $point->categoryIcon = $categories[$point->categoryId]['icon'];
-            $point->categoryName = $categories[$point->categoryId]['name'];
+            $point['categoryIcon'] = $categories[$point['categoryId']]['icon'];
+            $point['categoryName'] = $categories[$point['categoryId']]['name'];
         }
         
         self::renderPartial('json.php', array(