Why linker link static libraries with errors? iOS

Question

I have a problem with linking my mixed language framework to a project.

1) I create a framework with Swift and Objective-C classes.

2) The main logic was stored in the

Answer 1

An update to Alex's answer:

In my case it was a React-Native project after adding a Swift Pods library. Maybe just the step 2 can work:

1. Adding a new Swift file and a Brigde header:

1. File -> New -> File

2. Select Swift File

3. Confirm Create Bridging Header

2. Go to Build Settings and set Always Embed Swift Standard Libraries to YES