flash light with iOS

flashlight.m

//need to use AVFoundation framework 

/*
#import <AVFoundation/AVFoundation.h>
*/

 if(!self.flashOn) {
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    
    [device lockForConfiguration:nil];
    
    [device setTorchMode:AVCaptureTorchModeOn];
    [device setFlashMode:AVCaptureFlashModeOn];
	
	[device unlockForConfiguration];
	
    self.flashOn=YES;
    
    [btn setImage:[UIImage imageNamed:@"light_on.png"] forState:UIControlStateNormal];
  }
  else {
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    
    [device lockForConfiguration:nil];
    
    [device setTorchMode:AVCaptureTorchModeOff];
    [device setFlashMode:AVCaptureFlashModeOff];
    
    [device unlockForConfiguration];
    
    self.flashOn=NO;
        [btn setImage:[UIImage imageNamed:@"light.png"] forState:UIControlStateNormal];
  }