My iOS library (a dynamic xcFramework) uses URLSession to perform some networking tasks. It targets iOS 13 and higher. I set
configuration.tlsMinimumSupportedProtocolVersion = tls_protocol_version_t.TLSv13
to mitigate outdated TLS attacks. So far so good.
But now I must support iOS 12 as a target, and there is no tlsMinimumSupportedProtocolVersion there. What would be the best approach for me?
Related
Suppose I want to design a master detail application, Xcode6 master-detail project template for universal app includes UISplitViewController and splitViewController is new in iOS8. I want to support app for iOS7 also.
In general
What is the best way to design an universal app using Xcode6
storyboard that support both iOS8 and iOS7 ?
Is it better to use separate story board for different OS version ?
What are the best practices we should follow to make app compatible with both OS?
The 'best way' to create such an app will likely depend on what exactly your app needs to be able to do. Some ways will be better than others depending on any special behavior needed.
But it is definitely possible to use a single Universal storyboard in Xcode 6 that uses Size Classes and still target iOS 7, both iPhone and iPad, using UISplitViewController. I have successfully done just that. It did take a lot of work to ensure it worked properly and looked consistent on iOS 7 and 8. You have to be a little careful when it comes to performing the various new adaptive segues, as that is a huge difference between iOS 7 and 8. For example, detecting when you have a popover is going to require some work for the two different OSes, handling unwind segues will require some special handling, etc. It will require a lot of testing. Dedicate time to testing the iPhone 6 Plus - in landscape it will show both the master and detail on screen, but you can have control over that.
After going through that experience, I would much rather implement a single storyboard as opposed to two storyboards, one for each OS, and definitely stay away from creating a storyboard for each OS and then one for each device type.
You'll want to read up on the SDK Compatibility Guide to learn how to detect API availability. If you implement an API that doesn't exist on iOS 7 the app will crash, so you need to only run that code if that function exists for the OS the app is running on. For example, you may want to utilize the new UIBlurEffect API, but that doesn't exist on iOS 7. Gain an understanding of what deprecation means, and knowing what has changed in iOS 8 will greatly help. For example, the rotation APIs are deprecated in favor of Size Class trait collections, but those aren't available on iOS 7 so you'll need to continue to use the deprecated rotation API.
Also check out some WWDC videos from this year. They have a couple videos that discuss the new adaptive segues and Universal storyboards. Note that these storyboards ARE backwards compatible with iOS 7, but there are some size classes that aren't made available on iOS 7. See this question and the answer I provided for more information. WWDC videos from previous years also discuss how one can support multiple OSes, progressive enhancement, etc.
And of course when you have questions/problems Stack Overflow is a great resource. A lot of the questions I've posted in the past few months are related to this topic exactly, how to modify UISplitViewController behavior, obtain support for both OSes, using a single storyboard and the new adaptive segues, etc. You may wish to read through those to get an idea of what you can expect to run into when developing an app in the same fashion.
Following apple's new ios8 framework support, I wanted to know if apple also provides background compatibility with those frameworks on ios7 devices.
If so, what is required to achieve this back compatibility? If no, is there any best practise suggested for this situation?
I've just installed ios7 on my iPhone, however I have not yet downloaded xCode5, so I've been producing my archives using iOS6 SDK and using TestFlight to test them on my phone. When running my app on iOS7, I'm noticing a lot of bugs that I didn't see in iOS6 (some that are unpredictable and very difficult to fix). I've been avoiding downloading xCode7 because I'm not yet ready to make the commitment to the new UI elements, but I'm wondering if I did produce my app using the iOS7 SDK, is it possible some of these bugs could be eliminated?
This is a very broad question. iOS 7, despite its advanced beta count, is still very much a work in progress. There are bugs that should be reported to Apple that should not happen. But beyond that, there are changes in the internal API that influence how the app behaves. Apple has done its best to try and preserve SDK 6 apps as much as possible, but there is breaking API which can cause crashes. One example off the top of my head is the class cluster they are now using with ABPersonViewController. Subclassing that in iOS 6 works fine, but in iOS 7, even when compiled with SDK 6, causes a crash in most cases. These issues can be resolved even with Xcode 4.6 and SDK 6.
Compiling with SDK 7 may help you fix some issues, but it will come with a plethora of issues of its own. Depending on how complex your view hierarchy is, you may have to invest a considerable amount of effort to support the new API and functionality. You don't really have a choice, as this is the future, but you should be prepared for this, and arrange your schedule accordingly.
I am building my app using iOS 5.0 as base SDK and iOS 3.0 as deployment target.
I know I need to check for existence of methods and classes when I work with features that are not available in the earlier iOS versions, but lately I've lost a few hours on a problem just to discover I was calling a method not available in some iOS versions. I simply did not notice it was a new method and did no check before to call it. The app of course compiled with 0 errors and 0 warnings.
This is a big problem because if I forgot some other check somewhere in the app, I will not know it until I or, worst, some user will activate that specific part of code.
Maybe I am missing something, is there some compiler option I can set to detect the calls I make to methods not available in the iOS deployment target? How do you deal with such a problem?
This link might point you in the right direction. Supporting mutiple ios Versions in your apps. It explains how to deal with taking advantage of the newer ios features while maintaining backwards compatibility. Hope that helps.
The only way to check for compatibility with a prior version of iOS, currently, it to test the app on an old non-updated device running that version of the OS.
If you can't find a device that old, even just to borrow for short time, then there may not be a good buiness reason to set the Deployment target that low.
iOS SDK is upgrading, and some new tech will appear, i.e, block is new tech.
So question is if "block" based implementation also can be distributed to lower target version or older iPhone ( 3G or first generation ) ?
how to cope with those issues ?
The usual way to deal with this sort of issue is to selectively enable features at runtime based on the current OS version. However, this can be very complicated to manage.
Query the current OS version at runtime
Use weak linking
Dynamically create the class
Call the new features only if the new class is present
For example:
Class optionalClass = NSClassFromString(#"NSArtificialIntelligence");
if (optionalClass) {
id optionalObj = [[optionalClass alloc] init];
// ...
}
The following documentation describes the process in detail:
Configuring a Project for SDK-Based Development
Using Weakly Linked Classes in iOS
You specifically mention blocks. This feature requires support from the compiler and Objective-C runtime, so it will not be available at all on older systems.
You must weak link to libSystem.B.dylib if you are using blocks for iOS4 or later. Because blocks are able to compile with the latest iOS SDK but iOS2,3.0 and 3.1 don't have blocks runtime.
iOS 4 app crashes at startup on iOS 3.1.3: Symbol not found: __NSConcreteStackBlock
(Besides, you can use blocks for iPhone 2.2+. Please take a look at plblocks.)