How Block screen ? (Without interrupting the app)

Is it possible to have your smartphone turn off the screen while the app is running? Using the proximity sensor?

And apps created with app inventor work in the background?

My goal is to develop an application that turns off the screen using the proximity sensor ... and work in the background ... use this function to be useful in other applications in android ...

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Currently, background services not available in MIT AI.

Apps are-not services. This means if you turn off screen, Android may kill the appwhen it requires memory.

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