一起构建Swift，Objective-C和静态C ++库

Question

I have a static library from a third-party SDK — it's the FIT SDK that encodes and decodes "Flexible & Interoperable Data Transfer Protocol", used for various sports and fitness equipment. It's a binary format, well-described in the SDK, which also comes with a bunch of CPP, C-Sharp and Objective-C examples — plus a static library built from CPP source.

From what everyone seems to say, I should be able to build my Swift app with the static library, including the requisite bridging header.

I made a screenflow ( https://vimeo.com/205082135 ) showing what happens, which is why I'm here.

I can get Xcode 8 (beta 3) to build a new, fresh project containing the library and even some Objective-C code. As soon as I add the bridging header, even with a rudimentary include, XCode craters with a Linker error, complaining that it can't find some class from the standard C++ library, like or . Smells like a configuration management issue with Xcode that I simply cannot sort out.

My sample project with the library is here: https://github.com/bleeckerj/Xcode-FIT-TEST

Has anyone seen this sort of thing before?

Answer 1

So, through some help and lots of time and trials I managed to solve the problem and answer my own question.

Effectively one needs an Objective-C wrapper around the C++ (or Objective-C++) class containing the code one wants to expose and call from Swift. Then there's the Bridging Header that exposes just that Objective-C class. This particular Bridging Header is This sounds easy, and now it in fact is easy — but it was a mystery to me. It's a long-ish story, so I explain it as part of a sample repository https://github.com/bleeckerj/fit-sdk-with-swift derived from the FIT SDK that answers the question with an example.

Hope this is able to help anyone who comes across this problem.