Question

以前我手动制作过Card.IO绑定。它正在编译，使用它的项目也是如此，但它会经常崩溃。

现在我正尝试从头开始使用ObjectiveSharpie重新创建绑定。绑定项目编译但是当我从另一个项目引用它时，我得到如下所示的编译器错误。

它将AVFoundation框架项显示为“未定义的符号......”，因此在Xamarin中的IOS Build选项下，我有“-cxx”选项。我尝试了各种方法组合来为项目添加框架： - 在CardIO绑定项目中修改[assembly：LinkWith（...，Frameworks =“...”）]。这导致我的主项目中无法识别的CardIO命名空间 - 添加-gcc_flags“-framework ...”。这导致编译器发现“找不到框架”消息我最后通过包含一个using AVFoundation来解析AVFoundation，然后在其类中请求类型名称为1，这样链接器就不会对它进行优化 - 在我的书中难以理解。

在下面的错误中，似乎缺少更多的框架，我相信std::...应该通过使用“-cxx”参数来解决

我没有想法如何使这个绑定编译并正常工作。

Undefined symbols for architecture armv7:
  "_AudioServicesPlayAlertSound", referenced from:
      -[CardIOCameraViewController vibrate] in libCardIO.a(CardIOCameraViewController.o)
  "_CMGetAttachment", referenced from:
      -[CardIOVideoStream captureOutput:didOutputSampleBuffer:fromConnection:] in libCardIO.a(CardIOVideoStream.o)
  "_CMSampleBufferGetImageBuffer", referenced from:
      -[CardIOVideoFrame process] in libCardIO.a(CardIOVideoFrame.o)
  "_CVPixelBufferGetBaseAddressOfPlane", referenced from:
      +[CardIOIplImage imageFromYCbCrBuffer:plane:] in libCardIO.a(CardIOIplImage.o)
  "_CVPixelBufferGetBytesPerRowOfPlane", referenced from:
      +[CardIOIplImage imageFromYCbCrBuffer:plane:] in libCardIO.a(CardIOIplImage.o)
  "_CVPixelBufferGetHeightOfPlane", referenced from:
      +[CardIOIplImage imageFromYCbCrBuffer:plane:] in libCardIO.a(CardIOIplImage.o)
  "_CVPixelBufferGetWidthOfPlane", referenced from:
      +[CardIOIplImage imageFromYCbCrBuffer:plane:] in libCardIO.a(CardIOIplImage.o)
  "_CVPixelBufferLockBaseAddress", referenced from:
      -[CardIOVideoFrame process] in libCardIO.a(CardIOVideoFrame.o)
  "_CVPixelBufferUnlockBaseAddress", referenced from:
      -[CardIOVideoFrame process] in libCardIO.a(CardIOVideoFrame.o)
  "_OBJC_CLASS_$_EAGLContext", referenced from:
      objc-class-ref in libCardIO.a(CardIOGPURenderer.o)
  "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::find(char const*, unsigned long, unsigned long) const", referenced from:
      cv::CommandLineParser::CommandLineParser(int, char const* const*, char const*)in libCardIO.a(cmdparser.o)
      (anonymous namespace)::split_string(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&)in libCardIO.a(cmdparser.o)
  "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::find(char, unsigned long) const", referenced from:
      cv::CommandLineParser::CommandLineParser(int, char const* const*, char const*)in libCardIO.a(cmdparser.o)
      (anonymous namespace)::del_space(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >)in libCardIO.a(cmdparser.o)
      cv::CommandLineParser::printParams()      in libCardIO.a(cmdparser.o)
  "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::rfind(char, unsigned long) const", referenced from:
      (anonymous namespace)::del_space(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >)in libCardIO.a(cmdparser.o)
  "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::compare(char const*) const", referenced from:
      cv::CommandLineParser::CommandLineParser(int, char const* const*, char const*)in libCardIO.a(cmdparser.o)
      cv::CommandLineParser::printParams()      in libCardIO.a(cmdparser.o)
      bool cv::CommandLineParser::get<bool>(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, bool)in libCardIO.a(cmdparser.o)
  "std::__1::__vector_base_common<true>::__throw_length_error() const", referenced from:

Answer 1

这是一个丑陋的，但最终很容易解决。在目标的构建设置中，在“其他链接器标志”中，我有以下内容：

-lstdc++ -ObjC -lc++

也就是说，libCardIO需要-lstdc ++和-lc ++。

另外，请确保已将“标准库链接”设置为“是”。

Answer 2

经过大量的猜测，试错和搜索输出中的每个特定错误后，我想出了一个有效的解决方案，将此属性添加到绑定项目中的.linkwith.cs文件中：

[assembly: LinkWith ("libCardIO.a", IsCxx=true, LinkTarget= LinkTarget.ArmV7 | LinkTarget.ArmV7s | LinkTarget.Simulator, ForceLoad = true
                     ,Frameworks = "AVFoundation AudioToolbox CoreMedia CoreVideo OpenGLES MobileCoreServices"
                     ,LinkerFlags = "-ObjC -lc++")]

我曾假设添加

-cxx -gcc_flags "-lstdc++"

到主项目的iOS构建应该做同样的事情，但事实并非如此，无论是否有这些额外的编译器参数，绑定都没有构建。

如果您需要绑定项目的副本，请询问。

为Xamarin iOS项目创建Card.IO绑定的麻烦

2 个答案: