Question

I’m trying to make a kind of brightness option panel. After typing this code:

NSString *string = [[NSString alloc] initWithFormat:@"%f", slider.value];

[[UIScreen mainScreen] setBrightness:string];

I got the following error:

Sending 'NSString *__strong' to parameter of incompatible type 'CGFloat' (aka 'float')

Why does this code not working?

Answer 1

You get this error because the brightness property is not a NSString, it is a CGFloat. Try:

[[UIScreen mainScreen] setBrightness:slider.value];