I have an iOS project written with Objective-C. I created an Swift class in the project, the bridging header file for accessing objective-c in Swift is generated successfull
This is not an exact answer but more of a workaround, but can save you time in some difficult cases. If you, as suggested by some of the the previous answers, can actually find the swift header buried inside the derived data folder, you are allowed to import it using the full path. This is not specific to the swift header, instead it can be applied to any header. Hope you can find this answer useful.