Accessing the ambient light sensor in iOS

Question

I\'m working on a project in which it is really necessary to access the ambient light sensor.

I searched a lot in Google and Stackoverflow, but couldn\'t find any usefu

Answer 1

To read the ambient light sensor data, you need to use IOHID in the IOKit framework (Reference)

http://iphonedevwiki.net/index.php/AppleISL29003

http://iphonedevwiki.net/index.php/IOKit.framework

Answer 2

I solve this problem With access to the camera

- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection: (AVCaptureConnection *)connection
{
 CFDictionaryRef metadataDict = CMCopyDictionaryOfAttachments(NULL,
sampleBuffer, kCMAttachmentMode_ShouldPropagate);
NSDictionary *metadata = [[NSMutableDictionary alloc]
                          initWithDictionary:(__bridge NSDictionary*)metadataDict];
CFRelease(metadataDict);
NSDictionary *exifMetadata = [[metadata objectForKey:(NSString *)kCGImagePropertyExifDictionary] mutableCopy];
float brightnessValue = [[exifMetadata objectForKey:(NSString *)kCGImagePropertyExifBrightnessValue] floatValue];

//THIS IS INFORMATION THAT COMES FROM THE SENSOR
_Sensor = [[NSNumber numberWithFloat:brightnessValue] stringValue];
 NSLog(@" %@",_Sensor);

dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, 0.5 * NSEC_PER_SEC);
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){


        if ([_Sensor isEqualToString:@"-5.575654"]) {

       // YOU CODE HER

        }
        else {

       // YOU CODE HER
    }

});

}