New iOS SDK Best Practices - iphone

Every iOS SDK release I skip all the beta releases simply because I never wanted to mess up my current software/SDK versions. I wanted to make sure xCode still worked fine for my current projects but I could still get a "BETA" version.
What is the best way to download the newest SDK's without messing up your existing versions?

Unfortunately, there is none. Installing a new version of Xcode might mess up with your settings. Also, a project created in Xcode N+1 (or updated with it) might not be openable in Xcode N.
For iOS N+1, it's even worse: Apple says that you can't roll back to iOS N after installing the beta. It used to work for my colleagues with iOS 6 -> iOS 5 though.
The only thing I can think of:
Install Xcode N+1 on another mac
Install iOS N+1 on another phone.

Just run multiple versions of Xcode on your machine. This has been straightforward since it became a self contained dmg package available on the App Store.
See my answer below for more information:
Can I deploy an iOS 5.1 SDK app to a device running iOS 6.0 from Xcode?

Related

How to deploy code on Xcode 4 to newer ios

I have a very old Mac which is currently running Mac OSX Lion. It has Xcode 4 on it, and I created an app using that. Is it possible to deploy this app onto a newer iPhone? If not, do have any options to reuse the code on a newer version of Xcode?
If you want to deploy app on a device running iOS version more current than your Xcode supports, you won’t be able to launch it directly from Xcode. Just build the app for a generic device and then install the app manually. E.g. https://stackoverflow.com/a/35044362/1271826.
Just to warn you, while you can often install apps built on old Xcode versions on contemporary devices, occasionally there are little OS changes that break apps (and going back this many OS/SDK versions increases the probability of that). If this happens, without a contemporary Xcode version it will be exceedingly difficult to debug/diagnose the issue. Also, needless to say, you won’t be able to take advantage of contemporary device features (like bigger screens or whatever).
One final caveat: You won’t be able to distribute this app to the App Store until you build the app using a contemporary SDK version, generally achieved by building using a recent Xcode version. Review the Apple’s Developer News for references to minimum SDK versions.
Xcode 4 did not have Swift built-in, iirc, so your code is likely to be Objective-C.
You will have to update stuff, but nothing major like the conversion from Swift 1 to 5 would require.

Attribute Unavailable: Defines Presentation Context is not available prior to Xcode 4.2 [duplicate]

I'm developing an app which is iOS 4 compatible, so my deployment target is set to iOS 4.0.
Whenever I drop a UINavigationController onto a UITabBar, I get these two warnings:
warning: Attribute Unavailable: Defines Presentation Context is not available prior to Xcode 4.2.
warning: Attribute Unavailable: Defines Presentation Context on iOS versions prior to 5.0.
The UINavigationController functions as expected, in fact, the entire app runs perfectly. But these two warnings are driving me nuts!
Also, the moment I delete the UINavigationController the warnings disappear.
Just uncheck the "Defines Context" checkbox in the attributes inspector. (Double-click on MainWindow.xib, select the navigation controller, then go to View->Utilities->Attributes Inspector.) That'll get rid of the warnings.
You are getting these warnings because you are using iOS 5.0 SDK features with a 4.x deployment target.
All, if not, most of the new 5.0 hotness, including ARC and Storyboards, is completely backwards compatible with iOS 4.x (I don't remember if 4.0 or 4.3 is the lowest supported version, check the docs), it will work as intended, but Xcode is going to warn you anyways.
You should be able to disable that warning if it really bothers you, but I wouldn't. That said, Apple does not currently accept applications built/archived with the Xcode 4.2 beta for submission to the App Store. This means you need to use Xcode 4.0/4.1 in a production environment.
Before we go any further, you should know that Xcode 4.2/iOS 5 is beta software, it is under NDA (you agreed to this when you joined the Apple developer program) and cannot be discussed in the public domain. This means you won't be able get much help from places in the public eye, like StackOverflow, as good as it can be. But, since I'm here and this is a very high level question, I can help :)
In the future, if you have iOS beta questions or issues, you should hit up the Apple Developer Beta Forums (an excellent resource, always search before you post), or #iphonedev on irc.freenode.net for not-beta stuff (I'll be there, say hi!)
If you're developing an application for release on the App Store:
You need to be developing with Xcode 4.0 or 4.1, Apple will not accept applications built/archived with 4.2. (I know I repeated myself, but people seem to miss this often)
And, although 4.2b7 supports developing for older frameworks better than previous Xcode betas have (by allowing you to install previous versions of the simulator), you will still find yourself accidentally using 5.0 SDK functions all over the place, as the code completion/interface builder very aggressively favors all of the new hotness. This is because the beta is for trying new things, not stable application development.
This means you need to switch back to using Xcode 4.0/4.1 for production, if you don't have it installed, or you overwrote the stable version with the beta, do not try to install 4.0/4.1 on top of the 4.2 beta, weird things will happen and both versions will start acting really weird and and Xcode will crash at least twice as often.
The best thing to do in this situation, is to follow the below steps. Make sure you don't skip anything, otherwise you'll have to restart the whole process.
Make sure you have your code committed and pushed up,
uninstalling Xcode like this temporarily removes git. (This was an
issue for me at work once)
Download the installers for Xcode 4.0/.1, and 4.2 if you intend to keep experimenting. (if you already
have both downloaded, this whole process won't take more than 5
minutes on an SSD)
Uninstall the Xcode beta from the command line using this command:
sudo <Xcode>/Library/uninstall-devtools --mode=all (more info here)
Restart your computer (this is important, do not skip it!!!)
Install the most recent non-beta version of Xcode and resume development.
If you want to use both versions of Xcode (4.0/4.1 and 4.2):
You must install the beta AFTER 4.0/4.1 is installed, otherwise you will be overwriting new things with old things, and this will give you many, many obscure headaches. I also recommend restarting between installations.
You need to install 4.2 after 4.0/4.1, and to a different folder (I use /Xcode4beta/, don't put it within the folder that contains 4.0/4.1, either). I've found I learn about the new hotness best if I keep separate iOS5 branches of my work, and update what I can when I have some free time.
If you have the iOS5 beta installed on your phone, and Xcode 4.0/4.1 won't let you build to your phone:
This is because Xcode needs to grab the debug symbols from the phone before it can be used for devleopment, but only the Xcode beta can do this for an iOS5 beta device, so follow these steps:
Make sure your phone is plugged in and turned on, and that your provisioning profile/certificates all check out.
Close the project in Xcode 4.0/4.1.
Open the project back up in Xcode 4.2, and check organizer. You should either already have a green dot next to your phone (assuming all of your provisioning is working), or it should be gathering the debug symbols. Let this finish, and then build your project. It doesn't need to be a successful build, nor do you have to install the application to the phone, sometimes you don't even need to build, Xcode can be a fickle mistress.
Close the project in Xcode 4.2.
Open the project back up in Xcode 4.0, you should now be able to build and install to your phone as you normally would.
Xcode 4.0/4.1 should now be able to use your device for development until you restart the computer.
Resolution is here:
How can I fix "Freeform Size simulated metrics are not available prior to Xcode 4.2" warnings?
You just need to change the development version of your xib file to Xcode 4.2 (default is Xcode 4.1)
View Controller and Navigation Controller setting or options name ( attributes inspector )
Define Context ( Checked ) unchecked.

How can I support both iOS 4.X SDK and iOS 5 SDK in my iPhone app?

I am writing an iPhone app in which I want to support the largest user base possible at this point in time (with minimal pain), so I decided that targeting IOS 4.3+ would be a good subset of users for my audience.
I started working in XCode 4.2, but reverted back to XCode 4.1 when I realized that the project templates had changed and everything seemed very intertwined with storyboarding, ARC, etc.
I have built out my application to the point I actually want to test on my device, which has iOS5 installed. When I attempt to use it though, I get this message as soon as I click 'use for development' in Organizer/XCode:
The project's build settings look like this:
My Question Is This: How do I get this application, built in XCode 4.1, to run on both iOS 4.3 and iOS 5 phones?
Are iOS SDKs not backward compatible? I come from Android development in which a less than current SDK will generally work on a newer SDK - is this different in the iOS world? And if so, how is this handled typically?
Any direction on how I should proceed would be greatly appreciated.
You can go ahead and open your app in Xcode 4.2 and it should still work. I've been working on a particular app since Xcode 3.x days and I'm nearly done, chugging along in Xcode 4.2 right now. It shouldn't be a problem. If you want to work with Xcode 4.1 you will be fine, but you won't be ale to use new features introduced in iOS 5.
There are several aspects of "cross-version" development to note.
Testing: You can only test on version of iOS that are included with your SDK, or that are installed on physical devices that you may have. The SDK generally comes only with the latest iOS, sometimes the previous one is included as well, but since Xcode 4 was released, the older SDKs have been progressively deprecated with each release. This is not to say that your app which is linked against the iOS 5 SDK won't run on older versions of iOS. It just depends on how you implement new features.
Features: In order to support older versions of iOS properly, you want to make sure that you don't implement new features without properly checking for the existence of classes, methods, and properties that were introduced in the newer versions of the OS. Unlike Android, you don't have to worry about a million hardware configurations. ;-)
Weak Linking: To support a new feature and still be compatible with older versions of iOS, you need to weak link against frameworks that you are using to implement new features. You can read more about that in the Apple Documentation on Weak Linking.
Deployment Target: The setting that prevents the app from loading on older devices is called the "Deployment Target". If you set this to 3.1.3, then your app will run on iOS 3.1.3 and higher. Remember that if you don't code the the proper version checking, your app may break.
ARC: You can choose to enable or disable Automatic Reference Counting when you create the project. ARC scans your program at compile time only, not at runtime, it doesn't break the app on older versions of the OS.
You need the latest version of XCode and the iOS SDK to install your apps onto your iOS 5.0 phone. That doesn't mean the inverse is true -- you don't need the same version of iOS on your device that you have installed on your computer.
Hope this helps!
You can use the latest SDK and simply set the "IOS Deployment Target" version to 4.3 in the project build settings.
XCode 4.1 doesn't support iOS5 in the sense that Xcode package doesn't contain the iOS5 SDK. So you must return to Xcode 4.2 and target your project for iOS 4.3 (you can also target it for iOS 4.0 with this Xcode version, but you will not be able to simulate it; you can even download older iOS 4.x package versions from the Xcode preferences menu if you really need to simulate them in your device).
You can opt-out of ARC if you want, this choice is given to you when you create the project, so don't worry; but consider that ARC does its magic at compile time only, not at runtime, so your backward compatibility will be kept if you decide to use this technology. Finally if you don't want Storyboard just pick the Empty app template and it will simply put in your project only the basic files. From this template you can create any iOS app, this is the approach I normally follow.

Xcode 4.2 Warnings when dropping Nav Controller on Tab Bar in IB

I'm developing an app which is iOS 4 compatible, so my deployment target is set to iOS 4.0.
Whenever I drop a UINavigationController onto a UITabBar, I get these two warnings:
warning: Attribute Unavailable: Defines Presentation Context is not available prior to Xcode 4.2.
warning: Attribute Unavailable: Defines Presentation Context on iOS versions prior to 5.0.
The UINavigationController functions as expected, in fact, the entire app runs perfectly. But these two warnings are driving me nuts!
Also, the moment I delete the UINavigationController the warnings disappear.
Just uncheck the "Defines Context" checkbox in the attributes inspector. (Double-click on MainWindow.xib, select the navigation controller, then go to View->Utilities->Attributes Inspector.) That'll get rid of the warnings.
You are getting these warnings because you are using iOS 5.0 SDK features with a 4.x deployment target.
All, if not, most of the new 5.0 hotness, including ARC and Storyboards, is completely backwards compatible with iOS 4.x (I don't remember if 4.0 or 4.3 is the lowest supported version, check the docs), it will work as intended, but Xcode is going to warn you anyways.
You should be able to disable that warning if it really bothers you, but I wouldn't. That said, Apple does not currently accept applications built/archived with the Xcode 4.2 beta for submission to the App Store. This means you need to use Xcode 4.0/4.1 in a production environment.
Before we go any further, you should know that Xcode 4.2/iOS 5 is beta software, it is under NDA (you agreed to this when you joined the Apple developer program) and cannot be discussed in the public domain. This means you won't be able get much help from places in the public eye, like StackOverflow, as good as it can be. But, since I'm here and this is a very high level question, I can help :)
In the future, if you have iOS beta questions or issues, you should hit up the Apple Developer Beta Forums (an excellent resource, always search before you post), or #iphonedev on irc.freenode.net for not-beta stuff (I'll be there, say hi!)
If you're developing an application for release on the App Store:
You need to be developing with Xcode 4.0 or 4.1, Apple will not accept applications built/archived with 4.2. (I know I repeated myself, but people seem to miss this often)
And, although 4.2b7 supports developing for older frameworks better than previous Xcode betas have (by allowing you to install previous versions of the simulator), you will still find yourself accidentally using 5.0 SDK functions all over the place, as the code completion/interface builder very aggressively favors all of the new hotness. This is because the beta is for trying new things, not stable application development.
This means you need to switch back to using Xcode 4.0/4.1 for production, if you don't have it installed, or you overwrote the stable version with the beta, do not try to install 4.0/4.1 on top of the 4.2 beta, weird things will happen and both versions will start acting really weird and and Xcode will crash at least twice as often.
The best thing to do in this situation, is to follow the below steps. Make sure you don't skip anything, otherwise you'll have to restart the whole process.
Make sure you have your code committed and pushed up,
uninstalling Xcode like this temporarily removes git. (This was an
issue for me at work once)
Download the installers for Xcode 4.0/.1, and 4.2 if you intend to keep experimenting. (if you already
have both downloaded, this whole process won't take more than 5
minutes on an SSD)
Uninstall the Xcode beta from the command line using this command:
sudo <Xcode>/Library/uninstall-devtools --mode=all (more info here)
Restart your computer (this is important, do not skip it!!!)
Install the most recent non-beta version of Xcode and resume development.
If you want to use both versions of Xcode (4.0/4.1 and 4.2):
You must install the beta AFTER 4.0/4.1 is installed, otherwise you will be overwriting new things with old things, and this will give you many, many obscure headaches. I also recommend restarting between installations.
You need to install 4.2 after 4.0/4.1, and to a different folder (I use /Xcode4beta/, don't put it within the folder that contains 4.0/4.1, either). I've found I learn about the new hotness best if I keep separate iOS5 branches of my work, and update what I can when I have some free time.
If you have the iOS5 beta installed on your phone, and Xcode 4.0/4.1 won't let you build to your phone:
This is because Xcode needs to grab the debug symbols from the phone before it can be used for devleopment, but only the Xcode beta can do this for an iOS5 beta device, so follow these steps:
Make sure your phone is plugged in and turned on, and that your provisioning profile/certificates all check out.
Close the project in Xcode 4.0/4.1.
Open the project back up in Xcode 4.2, and check organizer. You should either already have a green dot next to your phone (assuming all of your provisioning is working), or it should be gathering the debug symbols. Let this finish, and then build your project. It doesn't need to be a successful build, nor do you have to install the application to the phone, sometimes you don't even need to build, Xcode can be a fickle mistress.
Close the project in Xcode 4.2.
Open the project back up in Xcode 4.0, you should now be able to build and install to your phone as you normally would.
Xcode 4.0/4.1 should now be able to use your device for development until you restart the computer.
Resolution is here:
How can I fix "Freeform Size simulated metrics are not available prior to Xcode 4.2" warnings?
You just need to change the development version of your xib file to Xcode 4.2 (default is Xcode 4.1)
View Controller and Navigation Controller setting or options name ( attributes inspector )
Define Context ( Checked ) unchecked.

iPhone App Run Different iOS

I am getting a fat binary when I go to upload, and I want to make sure that my application can run across 3.0, well even 2.0. Is there a specific way to make sure that this will show when I go to upload. I am not using any specific iOS 4 features, and I only have iOS 4 in my xCode. How can I test different iOS version?
The only way as I could think of is test your app on real old OS version devices. Since Apple prefers its users to upgrade to new OS version as soon as possible, they don't actually provide an official way for developers to test such backward compatibility.
Another relevant questions would be, "can I downgrade my device OS version to an old one, so that I can test my app on them?" I once did a research on SO and other Apple forums, and the result I got was NO, we developers don't have a way to "officially" downgrade our device OS version. Yes there are exceptions, you can try jail-breaking and then downgrading.
For jail-breaking / downgrading your OS version, check this post, A TimeMachine taking my iDevice back to 3.1.2? .
Edited: It's actually pretty easy to make sure that users with old OS versions can downloaded and install your app. All you need to do is set the Deployment Target in Xcode to the lowest OS version you want (iOS 3.0 would be the lowest in Xcode 3.2.5).
However, you need to bear in mind that such Deployment Target only ensures that your app can be downloaded and installed on such old version OS devices. They don't ensure compatibility during runtime. You still need to test your app on real old OS devices to ensure compatibility.
I dont think u need to worry about app version 3.0 below because it is not supported anymore. but how to test on different version, make sure change the iOS deployment target as Thomas refered.
There is no currently supported way to do this.
No current Simulator or Xcode tool will ensure that an app is completely compatible with an OS version older than the SDK used. The 2.0 SDK is not compatible with the current development tools. There is no officially supported way to downgrade a device.
Furthermore, Apple no longer even accepts app submissions that have a deployment target lower than 3.0.
Even most old 1st gen devices, if you can find one on eBay, have been upgraded to iOS 3.1.3. But if you have access to an old device running iOS 3.1.3, you can use that for testing. Many developers keep an old used iPod Touch around for just his purpose.
People with devices running something older than 3.1.3 are not only a really tiny percentage of the installed base, but are very unlikely to be still buying apps for that device. Even large developers with staff and legacy hardware available for this testing rarely waste the time on this market.
Look into Project -> Edit Project Settings -> iOS Deployment Target: 3.13. And then build?
Edit according to comment: You still need to ENSURE your code is within the runtime scope, i.e. do checks like 'respondstoselector' before calling methods in question.