Xcode 5，iOS7和64位与32位

Question

I have an application that I have in the store and it supports 32bit(iPhone 4+) on iOS 6+

I now also have an iPhone 5S and I'm currently using Xcode five.

I was able to successfully run my app under iOS seven with minimal tweaking, just for a status bar.

I now want to release a version that support iOS seven (For look and feel of tableviews/controls) but also supports iOS six for my current users.

How can I build my up so it's compatible with iOS six and iOS seven?

Do I have to build an iOS six version and a separate binary that I submit separately for iOS seven?

Also I would like to support the 64-bit CPU/architecture in the iPhone 5S , how can I support this?

Looking in instruments my app is still 32 bit even running on iPhone 5s,

Do I have to build separate iOS six, iOS seven, and iOS seven 64-bit binaries? and submit each version separately to the store?

Answer 1

From Apple release notes:

https://developer.apple.com/library/ios/releasenotes/General/RN-iOSSDK-7.0/

You can submit 64-bit apps for iOS 7 today that take advantage of the power of the iPhone 5s. Xcode can build your app with both 32-bit and 64-bit binaries included so it works across all devices running iOS 7. If you wish to continue to support iOS 6 then you need to build for 32-bit only. Next month we will be making changes so that you can create a single app binary that supports 32-bit on iOS 6, as well as 32-bit and 64-bit on iOS 7.

I guess that you have to compile different binaries for each version (iOS 6 32 bit, iOS 7 32 bit, iOS 7 64 bit), until the update next month.

Answer 2

You need to check your Xcode build settings.

The first important settings are ARCHS where you specify if you are 32 bit only, 32 + 64 bit, or 64 bit only. 32 bit works anywhere, including iPhone 5s. 32 + 64 bit means your app runs faster on iPhone 5s.

The second important setting is IPHONEOS_DEPLOYMENT_TARGET. This is the lowest iOS version that your app will run on. If it is 6.0 your app won't run on iOS 5. If it is 7.0 your app won't run on iOS 5 or iOS 6.

The third important setting is SDKROOT. That's the SDK that you are using. Apple wants you to use the 7.0 SDK for any new apps.

With deployment target = 6.0, SDK = 7.0, you have to be careful not to use any code that is 7.0 only on an iPhone running iOS 6. So you have to write code like "if (iOS 7 function is available) { use iOS 7 function } else { use iOS 6 function}", as long as you want to support iOS 6.