IOS UIImagePickerController 不能全屏

添加以下代码可以使取景框全屏

CGSize screenBounds = [UIScreen mainScreen].bounds.size;

CGFloat cameraAspectRatio = 4.0f/3.0f;

CGFloat camViewHeight = screenBounds.width * cameraAspectRatio;

CGFloat scale = screenBounds.height / camViewHeight;

pickerController.cameraViewTransform = CGAffineTransformMakeTranslation(0, (screenBounds.height - camViewHeight) / 2.0);

pickerController.cameraViewTransform = CGAffineTransformScale(pickerController.cameraViewTransform, scale, scale);