In AppCode 2017.1.2, when I try import EventKit and write code using the EventKit framework, all references to it are flagged in the editor as "Cannot Resolve..." type errors. Here's how to reproduce:
1) Open XCode. Create a new Single View app called "eventFiddler"
2) Replace the code in ViewController.m with the code in this gist: https://gist.github.com/seanicus/dba273d4d3093765f77d64bd372d3e6a
3) Add the key "Privacy - Reminders Usage Description" to the eventFiddler Info.plist.
4) Run the app. Notice that it builds, runs and shows you the Reminders access request dialog.
5) Stop the app.
6) Open the project in AppCode.
7) Notice that in ViewController.m, after AppCode finishes building symbols, etc, that all references to EventKit stuff is flagged as "Can't Resolve Type". Also notice that in the upper right of the editor, there is a red exclamation point icon that, when hovered over, says there are 12 errors.
8) Build and run the app. Notice that the application runs.
9) Invalidate Caches and Restart.
10) Notice that all the errors are still flagged in the editor.
This also happens if I try to create a fresh project in AppCode.