handle when unlock the screen Windows Phone

Question

I have to make an app that appears when you unlock the screen and then forces you to type Pin code you have set before for authentication exactly the same one that Windows Phone has in Settings. I already made SetPin page and Pinlogin page, but the only way I can do to make it appear when you unlock the screen is to start the app and make it run under the lock screen and use unobscured event to call it. But the Assignment requires to only setLock one time and no need to run the app again, it will appear when unlock the screen like the original one in WP, but I have no clue how to do it, how to start navigating to a page in your app when your app is not run and how to get the event when unlock the screen without running an app. It makes no sense for this assignment because I think we can not stop the start button on device even when I am successful at it.

Answer 1

Not possible with the current API.