+ /**
+ * Get values submitted by the user.
+ *
+ * These values have been validated against the fields added to the form.
+ * https://pear.php.net/manual/en/package.html.html-quickform.html-quickform.exportvalues.php
+ *
+ * @param string $fieldName
+ *
+ * @return mixed|null
+ */
+ protected function getSubmittedValue(string $fieldName) {
+ if (empty($this->exportedValues)) {
+ $this->exportedValues = $this->controller->exportValues($this->_name);
+ }
+ return $this->exportedValues[$fieldName] ?? NULL;
+ }
+