diff --git a/ngrest/base/ActiveWindow.php b/ngrest/base/ActiveWindow.php
index <HASH>..<HASH> 100644
--- a/ngrest/base/ActiveWindow.php
+++ b/ngrest/base/ActiveWindow.php
@@ -38,7 +38,7 @@ abstract class ActiveWindow implements \admin\ngrest\interfaces\ActiveWindow
         return $this->_itemId;
     }
 
-    public function setConfig($activeWindowConfig)
+    public function setConfig(array $activeWindowConfig)
     {
         $this->config = $activeWindowConfig;
     }
diff --git a/ngrest/interfaces/ActiveWindow.php b/ngrest/interfaces/ActiveWindow.php
index <HASH>..<HASH> 100644
--- a/ngrest/interfaces/ActiveWindow.php
+++ b/ngrest/interfaces/ActiveWindow.php
@@ -10,5 +10,5 @@ interface ActiveWindow
 
     public function index();
 
-    public function setConfig($activeWindowConfig);
+    public function setConfig(array $activeWindowConfig);
 }
ActiveWindow setConfig must be an array.