Show part of ProcessWire page tree based on domain

ProcessPageListSubDomain.module

<?php

class ProcessPageListSubDomains extends Process{

	public static function getModuleInfo() {
		return array(
			'title' => 'Custom Page List to show only part of the the page tree',
			'summary' => 'List pages in a hierarchal tree structure',
			'version' => 100,
		);
	}

	public function execute(){
		$list = $this->modules->get("ProcessPageList");
		$host = $this->config->httpHost;

		switch ($host) {
			case 'somedomain.com':
				$list->set('id',12345); // parent pageID for the subdomain
				break;

			case 'otherdomain.com':
				$list->set('id',67890); // parent pageID for the subdomain
				break;

			default:
				# code...
				break;
		}

		return $list->execute();
	}

}