How do I create in Xcode an iPhone project specifying at project creation time the SDK version I want to use?

Question

With the latest Xcode and SDK 3.0 beta when you create a new iPhone project, Xcode creates an SDK 3.0 project. If I want to revert to SDK 2.2.1 after the project has been created, I need to change something in the generated source code files since some of the APIs have changed. Is there a simple way to specify at project creation time the SDK I want to use explicitly?

Thank you in advance

Answer 1

I can't comment specifically on iPhone SDK 3.0 as it's covered under NDA; there's a forum for disclosed developers at devforums.apple.com. But Roger Nolan is half right and half wrong. He's half right in that when any SDK is updated, the examples and templates in that SDK are updated to exploit it. That is, the templates may specifically use the new APIs in that SDK, and the code might plain just not work with earlier SDKs.

That said, you can save project templates from earlier SDKs and install them in a local directory (like ~/Library/Application Support/Developer/Shared/Xcode/Project Templates) for use with later versions of Xcode. The project template format itself hasn't changed; templates should be forwards and backwards compatible, but the content of the templates is usually locked to the SDK version it ships with and later.

Mr. Nolan is half wrong about building against earlier OS versions with later SDKs. That's why the earlier SDK packages are provided with the later distributions (they're not there just to make the downloads take longer). You can deploy against older OS versions with a newer SDK by setting the Deployment Target build setting.

There is the minor detail in that you probably shouldn't deploy production applications produced by a pre-production toolchain. But once version N is officially released, you should be able to use its toolchain to build for N-1, N-2, etc.