Cakephp Render XML errors in custom Exception.renderer - cakephp

Question

Based on the information here: Using a custom renderer with Exception.renderer to handle application exceptions
I'm creating a custom error renderer that renders in XML format.
Below is the sample code for the render function in app/Lib/Error/AppExceptionRenderer:
public function render() {
if (isset($this->controller->request->params['xml'])) {
$this->controller->viewClass = "MyXml";
$error = array(
'app' => array(
'error' => 'An unexpected error has occured.'
)
);
$this->controller->set('error', $error);
$this->controller->set('_serialize', 'error');
}
}
However nothing gets returned. I have done some echo within the if condition and that shows.
So is it because the viewClass is not initialized while its in AppExceptionRenderer::render() stage?
There were no errors either.
"MyXml" viewClass works perfectly in normal controllers too.

Answer 1

So apparently I was missing the render and send methods.
Here's the full working example.
<?php
class AppExceptionRenderer extends ExceptionRenderer {
public function __construct($exception) {
parent::__construct($exception);
}
public function render() {
// Handle errors
if (isset($this->controller->request->params['xml'])) {
Cakelog::error($this->error->getMessage());
$this->controller->viewClass = "MyXml";
$error = array(
'app' => array(
'error' => 'An illegal operation has been detected.'
)
);
$this->controller->set('error', $error);
$this->controller->set('_serialize', 'error');
$cakeResponseObject = $this->controller->render();
$this->controller->response->send($cakeResponseObject);
} else {
if ($this->method) {
call_user_func_array(array($this, $this->method), array($this->error));
}
}
}
}