How to keep iPhone screen from reducing backlight..?

My app shows a picture and then an mp3 plays over it, describi开发者_如何学编程ng the picture. The trouble is that the backlight on the screen reduces after 40 seconds or so, if the phone is not interacted with. How do I prevent the fade?...so that my picture doesn't go dark when they are looking at it.

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[[UIApplication sharedApplication] setIdleTimerDisabled:YES];

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Set UIApplication's idleTimerDisabled property to YES.

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For swift the code will be:

UIApplication.sharedApplication().idleTimerDisabled = true