after reading the apple SDK guide
https://developer.apple.com/library/mac/#documentation/developertools/conceptual/cross_development/Overview/overview.html
I'm still confused of how to make the mac app backward compatible & how to test them properly
I have an app, I run it and tested it on Mountain Lion 10.8 without any problem, however I want to make this app backward compatible so that other users can run it on a mac 10.6 - 10.7 machine.
I have an apple developer id and I can download the old versions of 10.7 and 10.6, but the problem is, I have a 2011 macbook air which is currently running 10.8, and that's the only apple machine that I have. Can I test the 10.7 and 10.6 by using vmware or parallels?
in my project settings, I set the target deployment to 10.6 (as I want 10.6 users to run my app), but should I set my SDK to 10.8 or 10.7? if I set the SDK to 10.8 but having the target deployment set to 10.6, if I fix all the xcode warnings will it run successfully on 10.6??
from the SDK drop down, I can only set to 10.8 or 10.7, but 10.6 is missing, how do I fix that?
thanks in advance
I develop on a 10.8 box and support back to 10.5. Just a couple of months ago we dropped 10.4 PPC support, and I'm still cleaning out some of the 10.2-specific code. This may get a little rant-y, but I've been doing old versions for a long time. I have some opinions on the matter.
No matter what Apple says in their docs, if you want to support 10.6, then build with the 10.6 SDK. Do not rely on distribution target.
I have had this discussion with the Xcode engineers, and while they hold to Apple's party line that you should always build with the latest SDK, they also acknowledge that it's generally insane to do so. If you build against the 10.8 SDK and mark your deployment target at 10.6, you will get no warnings for using methods that do not exist on 10.6. The only way you will discover that you've used a nonexistent method is that it might give you strange bugs when run on 10.6. That's insane.
Remember, OS X doesn't crash when you send an unknown selector. It just aborts the current runloop. So the bugs are even harder to track down then on iOS, where it crashes the app.
Sure, you can do weak linking. Talk about dangerous.... Yes, there are a few times this is useful, but the compiler gives you no warning if you don't do it correctly. If I'm going to do weak linking like this, I go the other way, linking against the old SDK and copying the new function's prototype into my implementation. That way I have documentation of every function I think I'm going to weak-link.
Download the old SDKs and symlink them into your Xcode distribution.
Guard them jealously. Apple will try to delete them every time you upgrade Xcode. Make your own copies and stick them in /SDKs or somewhere else away from Xcode. I provide a script called fix-xcode to manage the symlinks automatically. Am I bitter at Apple for their relentless insistance on deleting my old SDKs? Yes, I am.
You can run 10.6 Server in a VM legally. You can run 10.7+ Desktop in a VM legally. These are good ways to test your code.
Or you can do what I do and have a small pile of old MacBooks each with two or three partitions on them that you reboot all the time.
Now that 10.7 comes from App Store, it's a little harder to make VMs. My strong recommendation is to snapshot your image immediately after install, and make a clean backup copy of it. You'll want to be able to clone that image from time to time when you need to get back to a "raw" machine.
Get in the habit of squirreling away SDKs as they come out. 10.8 will be old some day. You might as well make a copy now while it's easy.
Whether you support individual dot-releases or not, it can be very helpful to keep around the upgrade packages for individual dot releases. When you encounter customers running non-current releases, it's nice to be able to check whether an "unreproducible" bug in fact is easily reproducible on their specific version. Whether this is worth it or not depends heavily on your product and customers. It was a life-saver for me when 10.4.11 made major changes to WebKit during a dot release...
Invest in a small NAS or a big external USB drive (though I've had trouble with those failing when used extensively, so I prefer a RAID). You'll need the space. You want to hold onto lots of VMs and lots of SDKs and sometimes even old versions of Xcode.
Adding to Rob Napier's great in-depth answer:
To use an old SDK, put the SDK (or a symlink) to it here:
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs
With XCode 7.3 or later, you need you to open this file and change "MinimumSDKVersion" (otherwise XCode will refuse to use the old SDK):
/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Info.plist
You can install multiple versions of Mac OS on a single machine, booting between each.
The SDK should be the latest (10.8).
See 2.
One alternative to 1 that I've considered (I am in the same boat) is to create a Snow Leopard Hackintosh using an old PC and just installing Lion and Mountain Lion on my MBP.
You need to do these settings :
1.Set the Base SDK to Current version of Mac (ex. 10.7)
2.Set the Deployment SDK to older version (ex.1.4)
Related
I actually built a Hackintosh to learn programming with Xcode. It runs on my Asus X555LA laptop. I downloaded the latest Xcode 9 GM build from the Apple Site (not from App store). After extracting, when I tried to install, it shows "You can't use this version of the application "Xcode" with this version of macOS; You have macOS 10.12. The application requires macOS 10.12.6 or later".
Is there any tweak to make it run on my Sierra 10.12 itself? I can't really think about upgrading the macOS version as it's a Hackintosh. I followed this guide to install macOS on my Asus laptop.
Xcode requires latest macOS, you have no choice, you need to upgrade the macOS version on your Hackintosh. Or better: Reinstall macOS in a recommended way on your PC, if you're doing Hackintosh... :)
The guide you linked is very poor... Never use premade install images, because these have been modified in an uncertain way, and you don't want to install a premade undocumented mess to your computer. It might be packed with threats, malwares, spy tools and so on.. It's the worst thing I can imagine in security aspect to install an OS image from uncertain source.
Also, there is no universal macOS installer for PCs - even though many are trying to find a way to create it: it's a bad idea and it will never succeed because there are so many PC parts, millions of differently built computers..
The only way to create a stable fully functional Hackintosh is to know your hardware and create an installer flash drive for that specific PC. First you have to download the latest macOS Sierra from AppStore, this is the only source that you can trust, because it's downloading from Apple's servers. Then install a small program, called Clover bootloader to the flash drive to make it bootable.
This is the only full and up to date guide for PC laptops. If you have questions, register to the linked site and start a new forum thread posting your questions. They will help you but please read this guide at least 3-4 times carefully because everything is described here.
I have developed a Cocoa App on Lion and now I would like to add compatibility with Leopard and Snow Leopard.
I tried to set the development target to 10.5 but it still has crash problems on Leopard and Snow Leopard.
I tried also to open the project with old versions of Xcode, but I get hundreds of compile errors (I guess it's because I can't compile the program with the old Mac OS SDK)
Do you have any advice about solving the retro-compatibility problems of Cocoa Apps?
I think it's generally not a very good idea to develop for the latest OS then try to support older OSes at the last minute. If you've used any APIs that were introduced in an OS later than the oldest you're trying to support, you'll have to rewrite code to avoid using those APIs. It's generally not worth the trouble.
That said, there's no secret to supporting older OSes. You just need to make sure that you only use APIs (classes, methods, functions) that are available on the oldest OS you're trying to support. You'll notice when looking at the documentation that for each method, under "Availability", it will tell you which versions of the OS include that method. Something like:
Availability
Available in Mac OS X v10.6 and later.
Assuming you don't use any APIs not available on an OS version you're targeting, all you need to do is set the deployment target to the lowest OS you're targeting, and build. You will of course also want to test thoroughly on each OS version you're supporting.
Your question would be easier to answer in more detail if you elaborated on the "crash problems" you're seeing on Leopard and Snow Leopard.
First, install the 10.5 SDK on your Mac. This may not be necessary, but do it anyway. You can find instructions on the Internet. Keep in mind that compiling with the 10.5 SDK will ensure compatibility, but you won't be able to use newer OS X features unless you load them dynamically.
Second, go into your .xib files and on the File Properties tab (first notch in the Inspector pane) disable auto layout and set the deployment target to 10.5.
I created an application for the latest version of Mac OS X (Lion). My application uses ARC. I would however like it to be able to run on earlier versions of OS X.
My xcode says the earliest deployment target I can go is 10.4
By setting it to 10.4 does that mean I have done all that is required for my application to run on earlier versions of the OS up to 10.4?
Any help would be awesome thanks
There are a ton of API differences between 10.4 and Lion. Without seeing your app I cannot say for sure, but I would expect that it would not work correctly on 10.4 without some major changes. My suggestion is to forget about 10.4. I would be surprised if even 1% of OS X users are still running it. Stick with 10.6+ and you should be fine.
Whatever you do, only support versions that you have the ability to test on. If you don't have the capability to test on 10.6 you might even consider just supporting 10.7. If you cannot test on all of your deployment targets then you are setting yourself up for some pain.
ARC isn't supported for OS X 10.4 or 10.5. ARC is supported on 10.6, but has some problems that are not present on 10.7 (see question on this site). This isn't a show-stopper, but you should be aware of it if you use weak references.
According to Chitika (source), based on web traffic as of November 2011, 94% of Mac users were using 10.5 or newer and 72% were using 10.6 or newer. Those who haven't upgraded to 10.6 are less likely to be paying customers.
In my experience, developing a Mac application against an older SDK generally works without a hitch, but if you don't have access to an older system then you should warn your users that your application is untested on older systems. This is an unfortunate reality for independent developers. For example,
This application has been tested and runs on OS X 10.7. It may also run on OS X 10.6 but it has not been tested. OS X 10.5 and earlier are not supported.
To put it in perspective, OS X 10.4 was released in 2005. The last security update for it was 2009.
I've been developing for the Mac for the last 10 years, and my rule of thumb is it's usually OK to target the current OS version and only the previous one. Maybe even just the current version, if there's a compelling reason (new API) or the public knows a new OS version is coming out soon.
Example: in Spring 2012 everyone knows that OS X 10.8 will be released in the Summer, so new products I'd develop just on 10.7 with an eye towards 10.8.
There are a few markets where you'd want to do anything different (education being one), but these are few, far between, and usually only apply to long standing products.
I'm planning to buy Mac OS Lion, but I would like to know some informations.
- Are Snow Leopard's apps compatible with Lion?
- Are apps compiled with Xcode for Lion compatible with Snow Leopard? What if these app uses popovers/fullscreen which are features of Lion?
xCode requires a full download (the full 5*ish GB) and if you are a Java guy you will have to re download Java as it is not included (this was my experience when opening eclipse for the first time in Lion).
Some of Snow leopards apps are compatible, not all (ppc apps will not work). It is probably best to check with the software vendor first.
Another thing your Library folder disappears on an upgrade among some others where Lion is trying to 'Protect' its users. To get round this simply enter the command into terminal. (replace username with your username and foldertoreveal with the hidden foldername)
chflags nohidden /Users/Username/FolderToReveal
The upgrade process other wise has been fine. For reference I am an Obj C /C++ /C and Java developer. Hope this helps
Also will link you to this post about Developing Java on Lion:
Stack Overflow post on Java in Lion
A very good list of compatible applications is available at RoaringApps. I highly recommend checking for your favorite editors/IDEs/etc there.
Of note:
TextMate: "Works fine," but there are some issues
BBEdit: "Works fine"
iTerm2: "Works fine" (minor interface bugs)
And of course, Apple's tools require an upgrade to XCode 4.1.
As far as developing with the new APIs in Lion, you can explicitly target a specific version of OS X for compatibility. When building for 10.6, those new APIs will not be exposed during compilation and you will get warnings about unrecognized selectors if you try to use them.
So far what I've noticed :
- make sure you install XCode 4.1 (not the same as 4.0, it's a free separate download), which fixes the Python includes mess
- go to terminal and type "java", this will trigger the download of the Java runtime
But I chose to avoid the burden of fixing all libs by going with a clean install of Lion (from a USB key)
cvs stopped working for me, but downloading Xcode seemed like an unnecessarily heavyweight fix. Adding /Developer/usr/bin to my PATH fixed it for me.
I've been building a basic Cocoa application with Core Data and Interface Builder, and no extra coding, frameworks, or header files. I sent it to someone to test on their machine (a last-gen G5 iMac), and they got a message saying that their machine couldn't run it. I discovered the switch to compile for PPC, so I built a PPC version of the application to try out, and that produced the following error message:
You cannot use this version of Application on this version of Mac OS X.
I'm running Xcode 3.2.1, Interface Builder 3.2.1, and OS 10.6.2. The conversation with my tester was a bit confusing; at first it sounded like she only had Tiger on her machine, saying Leopard was incompatible (I corrected and said that Leopard should be, it's Snow Leopard that isn't), and then by the end of the conversation she was about certain that her machine was running Leopard, but had already shut it off by then. So I'm not sure which version of OS X is on the offending iMac, but it's the latest version of either 10.4.11 or 10.5.8 (the tester is in a remote location, so I can't verify personally at the moment).
What can I tweak to try and improve compatibility on my tester's machine?
If they're seeing that message, it's most likely because your app has the LSMinimumSystemVersion key (Minimum system version) set in the Info.plist. You should take this key out or set it to the actual the minimum OS X version you support.
Once you do this, you may well run into the next problem. (Probably a dynamic linker error as a result of using a framework or API that didn't yet exist on 10.4 or 10.5.)
The main problem here is that you're sending it out to a system where you haven't actually tried it. If you plan to support 10.4, 10.5, or both, I highly recommend that you find a spare hard drive, partition it up, and install 10.4.11 and 10.5.8. There are many issues that will crop up on older OS's and if you haven't tried it yourself, it's unlikely it will work smoothly on the first try.