fixed the form provider

src/Silex/Provider/FormServiceProvider.php

@@ -20,6 +20,7 @@ use Symfony\Component\Form\FormRegistry;
 use Symfony\Component\Form\Extension\Core\CoreExtension;
 use Symfony\Component\Form\Extension\Validator\ValidatorExtension as FormValidatorExtension;
 use Symfony\Component\Form\Extension\Csrf\CsrfExtension;
+use Symfony\Component\Form\ResolvedFormTypeFactory;
 
 /**
  * Symfony Form component Provider.
@@ -65,12 +66,16 @@ class FormServiceProvider implements ServiceProviderInterface
             return $extensions;
         });
 
+        $app['form.resolved_type_factory'] = $app->share(function ($app) {
+            return new ResolvedFormTypeFactory();
+        });
+
         $app['form.registry'] = $app->share(function ($app) {
-            return new FormRegistry($app['form.extensions']);
+            return new FormRegistry($app['form.extensions'], $app['form.resolved_type_factory']);
         });
 
         $app['form.factory'] = $app->share(function ($app) {
-            return new FormFactory($app['form.registry']);
+            return new FormFactory($app['form.registry'], $app['form.resolved_type_factory']);
         });
 
         $app['form.csrf_provider'] = $app->share(function ($app) {