Our company wants to distribute a closed-source SDK for iOS to our clients. I've been using Cocoapods to build the framework and built an example app making use of it. Previously the app worked fine on the simulator as well as when deployed on the device. However, I was also embedding the Pods.framework file in the app itself. One other piece of information that may be of interest is that the framework is written in Swift, the included cocoapods dependencies are both Swift and Objective-C.
I wanted to make the pods requirements easier to manage so the user doesn't need to be concerned with them and tried to embed the Pods.framework file inside of the SDK we're building - so I removed the steps to Embed Pods Frameworks and Copy Pods Resources from the example app, leaving them only in the framework, I also removed Pods.framework as a dependency of the example app, leaving it only in the SDK. This seemed to work in the simulator, but the app now crashes on mobile device with dyld: Library not loaded error.
Upon researching it, I stumbled into a few related discussions:
https://github.com/CocoaPods/CocoaPods/issues/344 https://objectpartners.com/2014/06/25/developing-private-in-house-libraries-with-cocoapods/
However, the suggested solution of using private pods does not look like it would work for us, it's my understanding that the source code in the private pod would still be open, and we can't share it with our clients.
Could someone advise on a solution that would work in this case?
OK, I finally have a more durable solution. It's a modified, cleaner version of my old one now that I understand how Xcode links in my Swift sub-frameworks better
Problem that makes distribution/compilation a bit ugly:
Since Swift standard libraries aren't bundled on the device like Obj-C, nor are they guaranteed to be stable between versions yet (stable binary interface promised in Swift 3: https://github.com/apple/swift-evolution#development-major-version--swift-30) we have to make sure the entire project is compiled against the same version of Swift. That means the guy using your closed-source framework has to be using the same version of Swift in their Xcode for their project as you did for compiling the library, even if he's not using Swift in his code because ultimately it's his version of Swift that gets bundled into the app and your SDK runs against. This is only an issue for closed-source frameworks because open-source ones will always be compiled against the same version as final project. Possible workaround is to restrict clients to same version you use or distribute multiple compilations (i.e. Swift 2.1 and Swift 2.0). To remedy this, you could provide users with copies of binaries compiled against multiple versions of Swift.
Aside from that, here is what I had to do during compilation/distribution to make a binary framework that works in Swift:
When building the framework:
In project target, make sure to add Pods.framework to Linked Frameworks and Libraries (make sure this is a pre-compiled RED version of Pods.framework, I had a black compiled Pods.framework in the same directory which built fine but then resulted in a framework that would cause the project to complain about missing armv7 architecture during linker phase in later project)
In Build Settings, under User-Defined section, add a field called BITCODE_GENERATION_MODE and set it to bitcode
DO NOT #import any frameworks in your bridging header, all instructions telling you to do that are leftover from Swift 1.0-1.2 days, you don't need it anymore and it does more harm than good (the later project will complain that it can't find these headers that aren't even exposed to it)
Change build target to Generic iOS Device, Archive and Export the framework
When building the project using the framework:
Drag and drop the framework into the project, in General tab add it to Embedded Binaries and Linked Frameworks and Libraries (you only need to add the framework itself, not the sub-frameworks or the pods file)
In Build Settings tab, add a new path to Framework Search Paths: $(PROJECT_DIR)/MyFramework.framework/Frameworks
Build the project
Related
I'd like to create a framework using Cocoa Touch Framework Project in Swift. However, I'm building this framework on top of another framework called RNCryptor, which is Objective-C based. I've seen various tutorials on how to create a framework in Xcode but none has covered a framework with its own dependency.
I tried to create a framework project and then using CocoaPods to manage its dependencies. However, there are errors appeared: 'Check Dependencies' Unable to run command...'
So the question is: is it possible to create a framework on top of another framework in Xcode. And if so, how?
Frameworks should never embed other frameworks directly. This leads to collisions if the importing project or any other framework also includes that framework. Instead, you need to tell your consumer that they also need to include your dependency. CocoaPods will do this for you automatically, so you should let it. (If you're having trouble with CocoaPods dependencies, you should ask a question about that and get it cleared up. The whole point of CocoaPods is to manage these kinds of things.)
Note that I will be releasing the Swift version of RNCryptor into beta today (or tomorrow, but I really hope today). This version bridges to ObjC and will be the preferred version going forward. (The ObjC version will continue to be available of course for projects that cannot or don't want to include Swift.)
Ever since Embedded Binaries were introduced in iOS 8, I have been wanting to port a lot of my common code into frameworks. I decided to wait one year before doing it and this year, with Xcode 7 Beta and iOS 9, I'm starting to do that just that.
I have started a Cocoa Touch framework project in Xcode 7 and I want to compile it into a usable framework. I can get it to compile my project into a .framework, but there's a few issues; namely, the framework doesn't appear to be importable into new projects (I will describe the steps I did for that shortly). Because of that, I'm not sure if my framework has any visible symbols.
This is what I have done to create the Framework:
Created my Framework as a Cocoa Touch Framework.
Went to my target's Build Phases, went to Headers, and added all my Swift files to the "Public" section, in hopes that will export all my simbols without having to mark them as public.
I tried to archive my project as a framework. Currently, it looks like Xcode 7 Beta 3 has a bug (going to report it later today) in which it generates corrupted archive files. For this reason I couldn't get my framework from the Organizer Window. To work around this, I changed the schema of the Run action in Xcode from Debug to Release, built it and grabbed it's generated .framework from my project's build/iphoneos-release directory. This was a quick test so I didn't need the frameworks generated for emulators.
And this is what I did to try to add the framework to a new project:
Created a "Frameworks" group (for organizational purposes) and dragged the framework there, selecting "yes" when it asked me if I want to copy the file to my project's directory.
Went to my target's settings, removed my framework from "Linked Libraries" (it was added there automatically), added it to Embedded Binaries instead. This added the framework to Linked Libraries again, so I had to remove it from there twice. Leaving the framework in Linked Libraries causes a linker error (can't find the framework - no idea why but I think it's irrelevant to my problem and something I should report to Apple as well), but once you remove it from there it seems to compile fine when you add it to Embedded Binaries.
Tried to import my framework in a file. Xcode complains there is "no such module".
Unfortunately, despite the fact that embedded frameworks have been around for around a year, I can't find much writing on the topic.
So my question is: Am I creating the framework correctly, making it possible that my framework/anything else is failing due to an Xcode 7 Beta bug? Or is there a different procedure to create a framework that I want to use as an Embedded Binary? I should probably mention that I want to make this library open source, and I think distributing a plain .framework file to the people who want to use it would be neat.
I Had the same issue on Xcode 7.
I solved it by editing the build settings of the project (the one which includes the framework).
By setting the Framework Search Paths field to $(PROJECT_DIR) or to the path to the directory that contains the .framework file it should help Xcode finding the module.
I know of familiar tutorials on this, but introduction of framework XCode 6 template has changed the game.
I already watched WWDC 2014 video about building modern frameworks but it talks more about building extensions, framework & app all inside single project. It does not specify if the framework I make with it is truly reusable across any project.
I am building framework the XCode 6 way (File->New Project->Framework and Library->Cocoa Touch Framework), but when I import it inside my test app project (separate from framework project) - I keep getting various errors.
Example: Include of non-modular header inside framework, and so on.
I know this is not what it says, and there are quite some missing steps in whatever I am doing. The older tricks may have worked for everyone, but I simply don't find which way to follow after XCode 6.
For example, there is some folder structure that a framework needs, but XCode 6 doesn't comply to it while building it. Is it right? If not, how can I change the way the XCode builds framework folder hierarchy?
Do I go back to old school or am I screwing some tiny thing in XCode 6 that I am unable to create a reusable framework?
I am not sure if you are trying to build a framework with Objective-C or Swift as your question doesn't state it. I've encountered errors you are mentioning with Swift so I'll give you my method to build Swift frameworks.
I found the process for Objective-C to be very straightforward and well documented, so I'll skip this.
As for Swift, there are a few things to consider. First, Swift static libraries are not supported, so you must exclusively use a framework (aka dynamic library) when linking an app to a library.
Here are the steps:
Create the Framework using New > Project under IOS > Framework & Library, select Cocoa Touch Framework
To avoid the "ld: warning: directory not found for option..." goto Library Search Paths in Build Settings for your target and delete the paths.
You can't mix Objective-C with Swift so don't even consider adding the Swift-Header bridge file in your code.
There are some cases in swift where you need to import code from unexposed Frameworks. I've successfully used the module-map inside the framework to deal with these case.
I also select CLANG_ALLOW_NON_MODULAR_INCLUDES_IN_FRAMEWORK_MODULES = YES in the Build Settings to solve 'include of non-modular header inside framework module'. That seems to work
I make sure that the header file that gets generated is marked as Public (not Project). Click on the file and you'll see the selection in the inspector under 'Target Membership'
You may run into some bizarre error messages when building. Xcode has a tendency to report linker errors when your code can't compile correctly resulting in missing files the linker needs to output its binaries. Sometimes XCode won't show the errors in the files you are compiling and you need to go manually on the build output and go back to the files. Some other time, you'll get a problem where you need to delete the cache. Those issues I call XCode blues and deal with it constantly. I found this type of problems happens more often when building libraries. The rest should work as expected.
I was able to create iOS Framework for Xcode as shown in that video:-
https://youtu.be/86cPaa3FrRg?t=4m55s
On 5:00 they say that framework must be added to Embeded Binaries.
If I add it to Embeded Binaries then it works.
It is not required to add GoogleAds.framework to Embeded Binaries.
Adding to Embeded Binaries looks a bit "hacky" comparing to Googles solution.
So I think this tutorial is missing some step.
My question is: How can I make a framework that works without adding it to Embed Binaries?
tl;dr They are both frameworks, but they are different types.
The term "framework" is ambiguous. On OSX it means a packaged dynamic library (i.e. .dylib, headers, other stuff), however before iOS 8 users could not create dynamic libraries so "static frameworks" were invented to provide packaged static libraries (i.e. .a, headers, other stuff).
If the framework you created needs to be packaged with the app as an embedded binary then it sounds like a dynamic framework, however if Google Ads doesn't then I suspect it's a static framework. It doesn't need to be embedded as it's already been linked into the app binary.
If you want to know how to create a static framework, then start here, or Google for "ios static framework".
Prior to iOS 8, developers shipped unsupported frameworks that were cobbled together with static libraries by mimicking the directory structure of Apple's frameworks. They worked, but they were a pain to build, and they were static—not dynamic—libraries.
As of iOS 8, Apple officially supports building third-party dynamic frameworks in Xcode. These types of frameworks are code-signed and must be placed in the Embedded Binaries for your app. If you link against them but fail to put them in Embedded Binaries, you will get an exception when attempting to run on device and your app will crash.
In the long-run, I would expect the hacked together frameworks like GoogleAds.framework to disappear now that official framework support is available. This means you'll have to get used to putting frameworks in Embedded Binaries.
Unless you need to support iOS 7 with your code (in which case official frameworks are not an option, because they only work on iOS 8), I would advise against creating an unsupported type of framework at this point.
I've created iOS Framework project using this method: https://github.com/jverkoey/iOS-Framework
Works pretty neat but I'm a little confused on how to include libraries/frameworks that are needed by my framework to work and, in particular, how to do it so that in case 3rd party client app that uses my framework can include these libs as well without conflicts.
Let's say my framework code needs these two things:
FacebookSDK.framework
libFlurry.a
The first one is an iOS Framework. When I add it to "Link Binary With Libraries" phase in my Framework and try compile the client project that uses my framework the linker complains about missing symbols - I need to add FacebookSDK to the client project which is great: there is no possibility of conflicts if client apps wants to use Facebook.
However when I do the same with Flurry static library I get duplicate symbols error when compiling client project. Which confuses me a bit, because isn't FacebookSDK.framework just a packaged static library?
ukaszs-iMac:FacebookSDK.framework lukasz$ file Versions/A/FacebookSDK
Versions/A/FacebookSDK: Mach-O universal binary with 3 architectures
Versions/A/FacebookSDK (for architecture i386): current ar archive random library
Versions/A/FacebookSDK (for architecture armv7): current ar archive random library
Versions/A/FacebookSDK (for architecture cputype (12) cpusubtype (11)): current ar archive random library
So my questions are:
why a library embedded in framework (like Facebook) is not linked to my Framework project product, whereas library included as .a file is?
how to include .a file in my framework so that it does not produce duplicate symbols error when client app using my framework also needs this particular static library?
For the use case you are describing, you should be linking to these external libraries from your application, NOT your own framework. It can be one or the other, but it can't be both.
If you decide that these dependancies belong as the responsibility of the application, you would remove them from "Link Binary With Libraries" and any other explicit linking configuration, and just project your framework project with the path to these frameworks and libraries so it can find the symbols (but not link against them) at compile time (i.e. the path to the libraries should be included LIBRARY_SEARCH_PATHS).
Use cocoapods , it's easy (http://cocoapods.org/)
Your application developers will have to include the podfile and download the dependencies.
While developing your SDK use a reference application/demo app on top of the SDK to simulate this.
You shouldn't link anything when building your framework but just create a *.a binary with your framework's objects.
Also you should not include code from other libraries in your framework as client applications may be adding the same libraries directly or requiring different versions of them, thus creating conflicts.
Off course you can reference *.h header files from other libraries in your framework in order to compile your objects.
As a result the installation steps for your framework should detail other required frameworks/libraries needed, their supported versions, how to add resource files (if any), etc. Just some of the many reasons why you may want to consider Creating a CocoaPods' podspec instead.
You should use CocoaPods. Your dependency on Facebook can be done by linking against the CocoaPod.
If you want to include that particular version of Facebook in your pod, you can put it in your repo and use the vendored_frameworks property to refer to it.
Similarly if you wanted to vendor libFlurry.a, you could do so using s.vendored_libraries.
For system libraries, you don't need to vendor them, e.g. libZ.a.
I strongly recommend creating your CocoaPod using pod lib create YourPodName. They've recently changed the mechanism for how this works and it's really nice.
You can create an Example project that shows how to use your code in context of an app.
Then one of the other neat things I just learned about, someone can do pod try YourPodName and it will automatically download, integrate and run the Xcode project.
CocoaPods is worth the trouble.
I am building my framework project using CocoaPods.
The framework uses some 3rd libs from CocoaPods.
Podfile specifies to install dependency on target of the framework.
When I build the framework, it includes all libs in the binary.
If I add use_frameworks! in Podfile, when the framework is built, it will not include 3rd party libs.
Use CocoaPods dependancy manager. Here's a good guide,
7 miniute video tutorial
Mostly if you install third party frameworks you can install with cocoapods (which is really nice, I would definitely do that) or they offer you to download the framework and include it in your Project.
If you decide to download the library and include it there is normally a list of frameworks you need in the "Getting started" guide.
Means: Offer them to install using cocoapods and to download your library but do not include anything else, give them a list what they need.