File in xcode project not found

Question

I am getting an error:

Error: Lexical or Preprocessor Issue: 'Constants.h' file not found

When the code is run, the issue disappears and the app works fine.

How can I fix this?

Answer 1

two things:

1. Do a product "clean" (CMD-SHIFT-K)
2. Avoid over-including headers from headers.

This involves using forward declarations whenever possible in headers (only #include another header if you are extending the class or implementing a protocol in that header). Use forward declarations for classes and protocols in your headers; then do the actual #import in your .m files.

@class SomeTypeINeedWhichIsAClass;
@protocol SomeProtocolWhichIsUsedInMyMethodSignatures;