I completed the CurrencyConverter example using Xcode 2.5 on Mac OS X Tiger 10.4.11, which I called CurrencyConverter2 since it was my second attempt. Since I've read that GNUstep is compatible with the Mac OS X Tiger version of Cocoa, I wanted to try building this Xcode project in GNUstep, which I am interested in learning.
I was able to install GNUstep on a VM running FreeBSD 12.0. I created a Makefile called GNUmakefile. Here are the contents of GNUmakefile:
include $(GNUSTEP_MAKEFILES)/common.make
APP_NAME = CurrencyConverter2
CurrencyConverter2_OBJC_FILES = main.m ConverterController.m Converter.m
CurrencyConverter2_RESOURCE_FILES = Info.plist English.lproj/MainMenu.nib
include $(GNUSTEP_MAKEFILES)/application.make
When building the program using gmake, it appears that everything was built correctly:
This is gnustep-make 2.7.0. Type 'gmake print-gnustep-make-help' for help.
Running in gnustep-make version 2 strict mode.
Making all for app CurrencyConverter2...
Creating CurrencyConverter2.app/....
gmake[3]: Warning: File 'main.m' has modification time 21869 s in the future
Compiling file main.m ...
Compiling file ConverterController.m ...
Compiling file Converter.m ...
Linking app CurrencyConverter2 ...
gmake[3]: warning: Clock skew detected. Your build may be incomplete.
Creating CurrencyConverter2.app/Resources...
Creating stamp file...
Creating CurrencyConverter2.app/Resources/Info-gnustep.plist...
Creating CurrencyConverter2.app/Resources/CurrencyConverter2.desktop...
Copying resources into the app wrapper...
However, when I try to open CurrencyConverter2.app, the main window does not show up at all.
My hunch is that for some reason my Makefile is not recognizing English.lproj/MainMenu.nib.
I also tried using a tool called buildtool that is able to build Xcode projects using GNUstep, but it complained that it couldn't find English.lproj even though it is in the directory that I ran buildtool.