- (IBAction)openFlash:(id)sender {      AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];      if ([device hasTorch] && [device hasFlash]) {          [device lockForConfiguration:nil];          if (hasClosed) {              [device setTorchMode:AVCaptureTorchModeOn];          } else {              [device setTorchMode:AVCaptureTorchModeOff];          }          [device unlockForConfiguration];      }  }