Screen-lock with running app, such a thing?

[flathunt]

Good morning all, I've searched but could not find, what I would like to do is to have an app running (say, the gallery viewer) and for any attempt to either exit with the home or back button to be met with a PIN prompt before it would exit. Something like app-locker but in reverse, where once you're in an app you have to be authorized to leave. Does anyone know of such a thing or should I write it?

Thanks, Flathunt.

 

[UncleMike]

Tasker can do that. In fact, I've done it with Tasker. My son wanted to use my phone to play a game while we were in the car. I setup a Tasker profile that did nothing when the game was started, and locked the screen when the game exited, Then I started the game and handed him the phone.