问题

NB: This is related to this question on project structure, but I have decided to a vastly the use-case to better abstract the problem.

Problem

How do I include afnetworking in my iOS App and an accompanying iOS Extension (ios8-extention, ios8-today-widget or ios8-share-extension) via CocoaPods?

Issues

For use in Extensions, AFNetworking needs to be build with #define AF_APP_EXTENSIONS, does this mean I need 2 versions AFNetworking? One for the Extension and one for the App?
How do I set up the Podfile so frameworks are built and copied to the correct places? Documentation on use_frameworks! is a bit thin.

回答1:

Update:

As Rhythmic Fistman mentioned the original answer's method gets overwritten when doing a new pod install.

Aelam provided the following method in this Github issue:

Add this to your podfile. remember to replace the target name

post_install do |installer_representation|
    installer_representation.project.targets.each do |target|
        if target.name == "Pods-YOU_EXTENSION_TARGET-AFNetworking"
            target.build_configurations.each do |config|
                    config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] ||= ['$(inherited)', 'AF_APP_EXTENSIONS=1']
            end
        end
    end
end

Obsolete answer:

1) Be sure that pod 'AFNetworking' is included for both targets (your container app and extension) in your podfile.

Example in my case:

target 'ContainerAppTarget', :exclusive => true do
  pod "SDKThatInternallyUsesAFNetworking"
end

target 'ExtensionTarget', :exclusive => true do
   pod 'AFNetworking'
end

2) In XCode, click on Pods on the hierarchy view to bring its build options. Then on the build options, select the target for which you are looking at the build options in the dropdown. There select Pods-{Extension Target Name}-AFNetworking (it should have been created automatically by pod install. Then select Build Settings. Then under Apple LLVM 6.0 - Language, verify that Prefix header has a filename. That filename on my case was Target Support Files/Pods-{Extension Target Name}-AFNetworking/Pods-{Extension Target Name}-AFNetworking-prefix.pch. If it doesn't have such a filename or similar then add it.

3) Go to that prefix header file that was named there or you added there. It'll be almost empty, then add the following line at the end:

#define AF_APP_EXTENSIONS

That should allow your container app to point to a version of AFNetworking built normally and your extension app to another built with the flag set. So only one version of the library but built in two different ways, each on one of the targets.

回答2:

For newcomers to this post, things have changed a little.

I spent a fair amount of time hitting my head against a wall, hopefully this will spare some of you from that same fate.

Cocoapods changed so that it now only generates one library per pod, so in order to properly set the AF_APP_EXTENSIONS macro, it actually needs to be set in the AFNetworking target, not your extension's target.

For example (with some pretty log statements):

post_install do |installer_representation|
    installer_representation.pods_project.targets.each do |target|
        puts "=== #{target.name}"
        if target.name == "AFNetworking"
            puts "Setting AFNetworking Macro AF_APP_EXTENSIONS so that it doesn't use UIApplication in extension."
            target.build_configurations.each do |config|
                puts "Setting AF_APP_EXTENSIONS macro in config: #{config}"
                config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] ||= ['$(inherited)', 'AF_APP_EXTENSIONS=1']
            end
        end
    end
end

Also worth noting the pods_project in installer_representation.pods_project.targets.each do |target|

Cocoapods has deprecated project and it has been changed to pods_project

The one somewhat downside to this is that AFNetworking won't use any UIApplication APIs in the container app either, but that was a non-issue in my project.

Hope this helps.