public function imageChangeByUpload()
    {
        $formName = $this->owner->formName();
        if (!empty($_POST[$formName][$this->imageAttribute]) && $_POST[$formName][$this->imageAttribute] == 'empty') {
            // reset image
            $this->imageReset();
        } else {
            // upload new
            if (!empty($_FILES[$formName]['tmp_name'][$this->imageAttribute])) {
                $this->imageChange(
                    [$_FILES[$formName]['name'][$this->imageAttribute] => $_FILES[$formName]['tmp_name'][$this->imageAttribute]]
                );
            }
        }
    }