objective c - Error: Undefined symbol for architecture x86_64: "OBJC_CLASS_$_InventoryItem", referenced from: objc-class-ref in AppDelegate.o -

what should solve problem? created both inventoryitem.h & inventoryitem.c files don't understand problem.

have re-created build scheme project? e.g.

1) product menu > schemes > manage schemes 2) delete scheme corresponding prohect 3) click on "autocreate schemes now"

build again.

if doesn't work, take in build phases, , ensure .m file class in compile sources stage.

the last thing can think of is, trying import ios classes mac app or visa-versa?

e.g. in ios app:

import cocoa 

e.g. in mac app:

import uikit 

it's highly unlikely, can cause similar errors.