simple activity to be called "on Idle"

create a simple no brainer activity and have it activated when android screen is just about to turn off. i don't care about the content of this activity, i only care about how to wire it so that it goes visible whenever the device screen is about to go black. the test this app will need to go though is simple: 1. i will configure the device to screen timeout = T secs 2. user quiet for N secs => activity becomes visible (INSTEAD of screen turning off) 3. user close app and keeps quiet => after N secs activity becomes visible etc. pls make sure you understand before bidding! Thanks, Steve