Do I have to compile my iPhone app with 4.2? - xcode

I have iPhone application in the App Store. Do I have to compile my app with iOS 4.2 SDK in order to allow it run on iOS 4.2 devices? Or compiling using iOS 4.2 is required only to allow using new features of new iOS?
I will appreciate if you can clarify this issue...
Thanks!
Yoash

Do I have to compile my app with iOS
4.2 SDK in order to allow it run on iOS 4.2 devices?
No, it will run on the new firmare just fine. At least if the new firmare does not reveal some bugs in your code (which happens).

You don't need to recompile it to let it run on newer OS versions, but like you already guessed, you need to recompile it when you want to use the newer features (eg. AirPlay, "Multitasking" etc).

The old version should still run.
The app might not play well with new features like multitasking on iPad, so it is worthwhile trying to get some testing and feedback done as soon as you can in case there are issues.
If you download the XCode 4 pre-release from the developer portal, you can use the new static analyser to look for problems in the code: this is not just for SDK issues but also things like memory leaks.

Apple recommends that you always compile with the latest SDK, even if you are targeting older versions.
Unless you run into a specific issue that is causing incompatibilities, it is wise to take this advice. A lot of small bugs and performance issues are fixed with each new iteration of the SDK.
That being said - you can continue to use the older SDK's, and Apple will still accept the apps you build. For mature apps that are only going through minor tweaks, this is probably the safest course to avoid introducing new bugs.

Related

Xamarin UI test alternative

I started using Xamarin.UITest for cross-platform testing (IOS & Android).
With Android it worked instantly without any problem and it keeps forking even after any SDK update or JDK.. name it!
But for iOS there was so many issue encountered with the device agent that didn't want to start, the wrong Xcode commande one, the wrong Xcode. Some time it worked, but out of no where it crashes.. then you must clean, rebuild, retry, cross your fingers it doesn't crash or at least that it will launch..
But now April 19 2019, I had an iOS update, combine with an Xcode update and sadly, it doesn't work anymore. I made a lot of research and attempt to recover my test case:
Downgrade Xcode to 10.1
Downgrade Xcode commande line tool to 10.1
downgraded the OS!
To finally rethink it. It's not a good solid testing tool if it breaks at every updates.
On the AppCenter it still works for both platform. But to create your test, you have to run them locally.. You can't anymore with iOS and if you find how to make it work, let me tell you : "See you for the next update!"
So the question is:
What are the alternative to do some automated UI test for iOS & Android using Xamarin?
Xamarin.UITest Xcode 10.2 support
Sorry to hear about your difficulty with the Xcode update.
Unfortunately Xcode minor updates for the last several releases have tended to break local iOS simulator testing, and occasionally device testing. I've seen this be an issue since at least as early as Xcode 9.x versions.
For context, Xcode 10.2 support was added in this package: https://www.nuget.org/packages/Xamarin.UITest/2.2.7.2002-dev
If you or future readers of this discussion still do end up using Xamarin.UITest, I recommend checking the release notes when new minor versions of Xcode come out to see if that support has been confirmed. Typically the support has been added in the 1st Xamarin.UITest package released after a new minor version of Xcode has been released.
(I generally haven't seen this issue with patch versions though, for example Xcode 10.2.1 didn't seem to cause any issues when it came out if it was run against a test suite that was working for Xcode 10.2)
Other testing frameworks
As for other testing frameworks, if you're using App Center itself; then Appium (JUnit) or Calabash are both able to be used with App Center Test and can be used cross-platform to run against your IPA/APK, generally regardless of what was used to write the apps in the first place, like Xamarin.UITest. (Though each framework has slightly different set up requirements and limitations.)
Outside of App Center Test, there may be other testing frameworks you can use; but that gets more into individual developer opinion which strictly speaking is out-of-scope for Stack Overflow answers.
Appium Studio which holds all the pros of native Appium. It also supports parallel execution with built-in test reporting mechanism. They also provide cloud devices with which you can check whether it is feasible for your project. Check out their documentation for more features.

Developing app for 10.8+ but using 10.9 SDK

Mavericks is coming out and for developers that's always a busy time with all these new features and APIs to know about and use. For me, I think it is the perfect time to ask a question that has been bugging me for a very long time.
Here's the thing, in context: I am developing an app that I want to be able to run on 10.8 (so the target system is 10.8+). Right now I am using the 10.8 SDK. However, with the release of 10.9 comes some pretty sweet APIs that I would like to use in my app. I use them in my code, but then, of course, I have to compile my app against the 10.9 SDK. If I do that, can I still run the app on 10.8?
Or, in a more general way, if I compile my app against one SDK, can I still run it on a 'lower' Mac OS? If yes, can you explain how does it work under the hood (what is the compiler doing)? This is a mistery for me.
Generally speaking, Xcode disassociates the issue of the SDK and the Deployment Target of the app.
The SDK is determined by Base SDK, and the deployment target is determined by OS X Deployment Target. These both show up in the Build Settings tab for each target in Xcode.
When programming with different SDK and Target, you are responsible for making sure that you don't call methods or functions on an OS that doesn't have them. This is often facilitated by weak linking (in the case of new frameworks) and/or using -respondsToSelector: in the case of new methods on existing classes and frameworks.
In Xcode, under build settings, there is an option for target OS where you can pick 10.8. 10.8 applications are generally compatible with 10.9 so the compiled application will work with both OSs.
Don't expect the new Apis to work when running on a lower version. It doesn't work that way.

Xcode 4 & Mac OSX 10.3?

I'm new at programming on the Mac. I've got me a brand new copy of XCode 4.0. I've got people asking me what versions of MacOSX we'll be able to support but I'm not sure what to tell them.
I see options for selecting an "SDK" and other options for selecting a target version. It seems the lowest I can go is 10.4 though -- even though we'd like to support 10.3, if possible without a lot of pain.
My question is, could anyone give me a quick rundown of how sdk versions and target versions fit into this? As I'm coding, what kind of things do I need to watch out for to make sure I can still support the smallest version of MacOSX? Likewise, how do I figure the G4/G5 (PowerPC) versions of MacOSX into all this? For example, on Windows, if I write an app in c#, I know that all I need to do is make sure an appropriate version of .net framework is installed, regardless of the OS. Does something similar hold true for the MacOSX?
Thanks in advance.
I believe Apple has dropped PowerPC support completely, including Rosetta, in Mac OS X so 10.3 is out of the question.
If you want to support PowerPC, see this related question. It looks like a lot of work.
How can we restore ppc/ppc64 as well as full 10.4/10.5 SDK support to Xcode 4?
With the analogy to the .NET Framework, there isn't anything like that for Mac OS X built-in.
It is true for Mac OS X. If your program targets 10.3 SDK, it will be able to run on 10.3 or greater. I.e. the Base SDK project setting specifies minimum target OS version.
However, supporting 10.3 IS a lot of pain. Even 10.4 is not that easy, for example Objective-C 2.0 (most important, #property, garbage collection) is only available with 10.5 SDK or above.
The common solution in existing projects is to keep an old version of software available for 10.1-10.4 users, while the new versions will require 10.5 or greater (and also usually are Intel-only).
If you're starting a new project, you will probably want to distribute it via Mac AppStore, which only works on 10.6+, which means you can safely pick 10.6 SDK as the lowest target version.
Apple is way more harsh about upgrades than Microsoft. Mac users don't walk around with 10-years old systems on their laptops. The only reasons I can think of to still use 10.3 are using 10-year old mac, not having Internet connection and not knowing what “to update a software” means. So, I wouldn't care even about 10.4, not to say 10.3.

Explicitly set base SDK to 3.2 to catch compiler errors

We're building an iPad app and don't plan to use any APIs that are not available in iOS 3.2. Our deployment target is already set to 3.2, but I would like to set our base SDK to 3.2 so that we get compiler warnings/errors if we accidentally invoke APIs not available in 3.2, rather than runtime failures.
Is this a good idea? If so, is the 3.2 sdk still available for download, and will older sdks work with newer XCode versions, like 4? Thanks.
There's no guarantee Xcode will support older SDK versions but as an example the current install of Xcode 4 goes all the way back to 3.0. I would drop 3.2 if I were you (few iPad users are on that; most iOS apps enforce 4.X in the App Store so I'd bet most people have upgraded) but if you are going to support it perhaps you should consider using conditional code for different OS' versions.

Is Xcode 4 ready for iOS development or still too beta?

I am just starting iOS/iPhone development and I would like to start using XCode 4 instead of XCode 3.2. Is XCode 4 stable/feature complete enough for beginning iPhone development or should I stick with XCode 3.2?
I have run into far too many problems using beta versions of XCode, especially since you can't really have two versions of XCode one the same system. Apple already has a history of releasing things to developers before they are truly ready (just look at iAds for the iPad which were released months ago and have yet to deliver a single ad). So, if even Apple isn't ready to label XCode 4 as ready-to-go then you can rest assured its not really ready to go.
I recommend sticking with 3.2. That's what I'm doing until XCode 4 is officially supported.
Using XCode 4 calls everything you do into question. Having a problem with an API? Maybe it's XCode, maybe its your code, maybe its a bug in the API. You just don't know.
I would say no, it's not ready. I tried using it as my main development environment for about a week, and eventually switched back to 3.2. For one thing it crashed fairly regularly, but I could get passed that.
The big thing that caused me to switch back was a bug where the iOS simulator would think that certain resources existed in my app that didn't. Deleting the app from the simulator didn't work, cleaning the project didn't work, and deleting the derived data folder didn't work. Since it's not officially released, finding help for problems like this is a pain as well.
This is just one instance of the kind of problems you'll run into while using it, so I'd recommend avoiding it for now.
You can use Xcode 4 if you do not plan on using the current version (Preview 6) for submitting apps to the App Store.
iOS Dev Center:
Xcode 4 Developer Preview 6 includes
iOS SDK 4.2, bug fixes, and additional
features. To compile submissions for
the App Store, continue to use Xcode
3.2.5 and iOS SDK 4.2.

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