gistfile1.php

<?php

//...

public function onBeforeWrite() {
	$file        = $this->File();
	$fileChanged = false;
	foreach (['Title' => 'Title', 'Filename' => 'Name'] as $field => $fileMethod) {
		if ($this->isChanged($field)) {
			$fileChanged         = true;
			$file->{$fileMethod} = $this->getField($field);
		}
	}

	if ($fileChanged) {
		$file->write();
	}

	parent::onBeforeWrite();
}