访问UIImagePickerController的didFinishPickingImage返回的图像属性时获取EXC_BAD_ACCESS

Question

我现在正在模拟器中工作，当试图访问UIImagePickerController的didFinishPickingImage返回的图像属性时，我收到一个EXC_BAD_ACCESS错误：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
    NSLog(@"Image size: %@", img.size);
}

我做错了什么？

Answer 1

您正在尝试打印对象（“％@”格式说明符），但大小为CGSize类型，其类型为明文struct。使用

NSLog(@"Image size: %@", NSStringFromCGSize(img.size));

或

NSLog(@"Image size: (%f, %f)", img.size.width, img.size.height);

Answer 2

UIImage.size是a structure，不是对象，因此您无法在NSLog中使用%@来记录它。试试这个：

NSLog(@"Image size: %.0f %.0f", img.size.width, img.size.height);

Answer 3

请改为：

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
    NSLog(@"Image size: %f by %f", img.size.width, img.size.height);
}