Why does Xcode not find the headers in a folder reference?

Question

For example I drag in a folder "SharedClasses" with shared source code files as a folder reference into Xcode. The folder reference appears in the Project Navigator and lists all .h and .m files correctly.

But Xcode refuses to import them. I tried all kinds of import:

#import "Utility.h"

#import "SharedClasses/Utility.h"

#import <SharedClasses/Utility.h>

None of them work. But a folder reference exists and it contains "Utilities.h"

Xcode knows where the folder comes from so what must I do that it looks inside it?

Answer 1

Because the files are in a different folder than the project Xcode will not include it in the header search path. To fix this add an entry for User Header Search Paths (select your project, select Build Settings, filter to "user header search paths", add the value) in the project that points to the original folder reference. For example in a project I'm working on I have code that is shared between several projects in a workspace which is stored at the same folder level as the projects in a folder named shared. My User Header Search Paths has the following:

$(PROJECT_DIR)/../Shared/MySharedCode/