How to access camera flash on UIImagePickerController?

Question

I would like to know how to switch on the camera flash on the iPhone 4 with UIImagePickerController.

if ([UIImagePickerController isSourceTypeAvailable:UIImagePi         


        

Answer 1

You can use this. Basically call 'toggleTorch' when you want to turn the flash on or off. Hopefully this is what you were looking for.

- (void) toggleTorch {

    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

    if ([device hasTorch] && [device hasFlash]){

        if (device.torchMode == AVCaptureTorchModeOff) {

            NSLog(@"It's currently off.. turning on now.");

            [power setImage:[UIImage imageNamed:@"on@2x.png"] forState:UIControlStateNormal];

            AVCaptureDeviceInput *flashInput = [AVCaptureDeviceInput deviceInputWithDevice:device error: nil];
            AVCaptureVideoDataOutput *output = [[AVCaptureVideoDataOutput alloc] init];

            AVCaptureSession *session = [[AVCaptureSession alloc] init];

            [session beginConfiguration];
            [device lockForConfiguration:nil];

            [device setTorchMode:AVCaptureTorchModeOn];
            [device setFlashMode:AVCaptureFlashModeOn];

            [session addInput:flashInput];
            [session addOutput:output];

            [device unlockForConfiguration];

            [output release];

            [session commitConfiguration];
            [session startRunning];

            [self setTorchSession:session];
            [session release];
        }
        else {

            NSLog(@"It's currently on.. turning off now.");

            [power.imageView setImage:[UIImage imageNamed:@"off@2x.png"]];

            [torchSession stopRunning];

        }

    }

}

-(IBAction)powerBtn
{
    [self toggleTorch];
}