Please I need help here. For instance I have 4 web pages in a web application, and I want to execute a process through those 4 web pages. Lets say, if the first web page is running on the browser, the process should start. And if the second web-page is running on the browser, the process should continue to the second state. And if the third web page is running on the browser, the process should continue to the third state. And if the fourth web page is running, the process should end.

I'd really appreciate any help you can give. Thanks.