iOS 7 auto brightness is overruling apps screen br

问题:

I have an iOS 7 app where I want to make the screen darker. I am adjusting the screen brightness using the following line:

[UIScreen mainScreen].brightness = 0.3;

This dims the screen as I expect, but if a user has auto brightness enabled the screen sometimes goes back to its original setting. Is there a way to disable auto brightness while in my app, or do I need to subscribe to the UIScreenBrightnessDidChangeNotification notification and just reset the brightness each time it is raised?

回答1:

You cannot disable the auto brightness at all, so you will have to subscribe to the notification. Read more about available methods in UIScreen:

• https://developer.apple.com/library/ios/documentation/uikit/reference/UIScreen_Class/Reference/UIScreen.html#//apple_ref/occ/instp/UIScreen/brightness

• How to turn off Auto-Brightness programatically?

• Does iOS send notifications when the system changes the screen brightness?