如何使用动态网址为XERO回调网址

I have developed php laravel 5 web application. I need to connect with XERO account software. this application is public application. further domain is change with each account. Use sub domain for each application. How do I set callback URL?

1. PHP Laravel 5 web application.
2. Public application.
3. URL is changed for each account. (Eg:- http://dissanayaka2344.drilltracker.com/ , http://demov3.drilltracker.com/)
4. Need to connect with Xero.
5. How I provide callback URL.

Assuming you are using the Xero recommended PHP files from here:
https://github.com/XeroAPI/XeroOAuth-PHP/blob/master/public.php

You need to amend the following constant accordingly:
define ( "OAUTH_CALLBACK", 'http://localhost/XeroOAuth-PHP/public.php' );

Something like:
define ( "OAUTH_CALLBACK", "http://". $subdomain . "drilltracker.com" );