compile for 3.0 with optional support for 3.1 API

Question

My app uses the camera, and I added the zoom function thanks to 3.1 API (cameraViewTransform most importantly). But I want my app to run also on 3.0 (without the zoom of course). The problem is that, I cannot compile the app in 3.0 due to this line which calls 3.1 properties:

CGAffineTransform initialTransform = photoPicker.cameraViewTransform;

If it was a method then I could have used performSelector or something like that. Changing it to initialTransform = [photoPicker cameraViewTransform] doesn't work neither. Is there any solution for this?

Answer 1

You want to set your deployment target to 3.0, but then compile with the 3.1 SDK, checking at runtime for the availability of the functionality using [photoPicker respondsToSelector:@selector(cameraViewTransform)] before calling it. There's a rant about deployment targets and SDKs at http://groups.google.com/group/iphonesdk/msg/1f47eae223a9fe90?dmode=source that might be helpful.

Answer 2

I think this question is similar to yours, maybe the solution there might help you.