File not being uploaded

I have a hard trouble uploading a file to server, more exactly function hasFiles() return false each time my code is:

    protected function uploadForm() {
        $form = new Form();
        $form->add(new File("file", array()));
        $form->add(new Text("name", array()));
        return $form;
    }

    public function uploadAction() {
        $this->view->form = $this->uploadForm();
    }

    public function savefileAction() {

        $request = $this->request;

        if ($request->isPost()) {
            $this->flashSession->success('is post');

            $name = $request->getPost('name');

            $this->flashSession->success($name);

            if ($request->hasFiles() == true) {

                $this->flashSession->success('has files');

                foreach ($request->getUploadedFiles() as $file) {

                    $this->flashSession->success($file->getName(), " ", $file->getSize());

                    $file->moveTo('/public/img/' . $file->getName());
                }
            }
        }
    }

template:

    <?php echo Phalcon\Tag::form(array('admin/savefile',)); ?>

                <?php echo $form->render("file"); ?>
                <?php echo $form->render("name"); ?>

                <?php echo Phalcon\Tag::submitButton(array("submit")) ?>
    </form>

after submit the output s "is post" and "<name value>" so hasFiles() is always zero. please advice