diff --git a/src/Forms/EditFormFactory.php b/src/Forms/EditFormFactory.php
index 8455d94b..85bb883b 100644
--- a/src/Forms/EditFormFactory.php
+++ b/src/Forms/EditFormFactory.php
@@ -29,7 +29,7 @@ class EditFormFactory extends DefaultFormFactory
      */
     const FIELD_NAMESPACE_TEMPLATE = 'PageElements_%d_%s';
 
-    public function getForm(RequestHandler $controller = null, $name = EditFormFactory::DEFAULT_NAME, $context = [])
+    public function getForm(?RequestHandler $controller = null, $name = EditFormFactory::DEFAULT_NAME, $context = [])
     {
         $form = parent::getForm($controller, $name, $context);
 
@@ -44,7 +44,7 @@ public function getForm(RequestHandler $controller = null, $name = EditFormFacto
         return $form;
     }
 
-    protected function getFormFields(RequestHandler $controller = null, $name, $context = [])
+    protected function getFormFields(?RequestHandler $controller = null, $name, $context = [])
     {
         $fields = parent::getFormFields($controller, $name, $context);
 
@@ -58,7 +58,7 @@ protected function getFormFields(RequestHandler $controller = null, $name, $cont
         return $fields;
     }
 
-    protected function getFormValidator(RequestHandler $controller = null, $name, $context = [])
+    protected function getFormValidator(?RequestHandler $controller = null, $name, $context = [])
     {
         /** @var CompositeValidator $compositeValidator */
         $compositeValidator = parent::getFormValidator($controller, $name, $context);