How do you conditionally include a framework in an Xcode project?

Question

Is it possible to have a single Xcode project (and ideally a single target) that will conditionally include frameworks when built against a certain version of OS X / Xcode but not include those frameworks when built against another version?

I'd like to begin adding support for El Capitan to an application I'm working on but some of the support I have in mind requires linking against frameworks that are not present in Yosemite. Is there a way to configure an Xcode project so that the same project can be built under 10.11 / Xcode 7 with the frameworks but also built under 10.10 / Xcode 6 without the frameworks (and without throwing an error)?

I'm aware of how to check for the existence of a class or method at runtime, but it's not clear to me how I control the framework linking without creating a second Xcode project, a second source control branch or always building against Xcode 7 (none of which I want to do, yet).

Answer 1

The "other version" would essentially be another target — it's setup this way to do precisely what you're asking about. A basic example would be just a matter of right-clicking on your original target and selecting duplicate from the current targets; then make whatever changes to linking frameworks within the Build Phases section.

Targets

In Build Phases you'll notice I've linked three frameworks to my original target:

After right-clicking on the original target and creating a duplicate I'm able to link it differently:

The duplicate version of MyApp uses the same classes and headers as the original with the exception of those that require the excluded frameworks. It's also possible to import different frameworks, change things such as the Deployment Target (e.g. build for different versions of OS X), or perhaps which SDK each might use, etc.

Once you're more familiar with the standard build process you can then create custom build scripts to handle specialized tasks like keeping the target names the same or even creating installer packages — anything is possible.