I've read the "Using Swift with Cocoa & Objective-C" a few times, and I've tried every possible combination of project type (framework, static lib & Swift first, Obj-C first, the lot) but I simply can not get modules to work. I've spent more than 2 hours on this, and it shouldn't be that difficult. Chosing a module name and setting Defines Module to 'yes' doesn't do it.
My goal: to create a module that makes the Apple System Logging service available in Swift code. I've got an objective-c wrapper library lying around that I thought I'd make available as a module to import into my Swift framework, but so far the only luck I've had is it exposing only one of the many classes publically in Swift code. The rest simply aren't available. It's also exposed the 'asl.h' C functions, which is cool, but I have no idea how that happened. I tried creating several sparce frameworks/static libs with the sole goal of making 'asl.h' functions available in Swift. If someone knows how to do that (for any C headers that are part of iOS) without the need to create an Objective-C framework as a module to import into Swift, I'd love to hear about it. Or even just as a framework to make any c headers available in Swift that would be awesome.
So! I create a workspace with an app project in it, and then I create a framework project at the same root level in the workspace as the app project. On the framwork target I set the Product Module Name and Defines Module to 'Yes'. I update my My App's Scheme build target to include the framwork above the app target. I ensure the Link Binary With Libraries build phase contains the framework. Build the app target after adding an 'import MyFramework' line in a Swift file and boom. Failure.
Obviously I've tried clean builds, deleting Derived Data for all projects, hopping one leg and trashing everything and starting again. Someone, anyone, had success with modules yet?
Related
I am trying to create a CocoaTouch Swift Framework which I can then distribute to 3rd parties for them to use, and I can build it and use it ok on my machine.
The issues arise when I give it to other people.
My framework uses C code, which I make available for use with Swift within my framework via a module.modulemap file as such:
And I am able to use such module in a Swift file, within the framework, ok, as such:
However, when I build the framework and give it to other people to use, their compiler complains that the Minzip module is missing with the message Missing required module 'Minizip'.
Having investigated, it seems like I'd have to make the users of my framework modify their Swift Compiler - Search Paths -> Import Paths the same way I have to do it to have my compiler find the module.modulemap.
Is there a way that I can build the framework so that I don't have to do this?
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.)
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 wrote a class in Swift. I want to use this code in two separate iOS app projects that I wrote. Both the shared code and the apps are written in Swift. What is the best way of doing that?
I tried to create both a framework and a library in Swift and then add it as a sub-project to my app. In both cases I could not make the app see the module. I tried to add the shared module to "Target Dependencies" and "Link Binary With Libraries" of the main app's target. No luck - the app still can not see the classes of the shared module.
Using Xcode6 Beta6 at the moment.
Solution
As Konstantin Koval and Heliem pointed out, all I needed is to use public in my class and method declarations, in the shared module. Now all works, both if I use workspace and if I add the module as a subproject.
Update
I just found an excellent easy solution for reusing code between projects in Swift. It is called Carthage (https://github.com/Carthage/Carthage). This is not a plug as I am not affiliated with it in any way, I just really like it. It works in iOS 8+.
Create a new project (iOS Cocoa Touch Framework) for your reusable code
Move your classes to that Framework project
Mark your methods and classes, that should be visible to others as public
Create Workspace.
You can create a workspace on step 1. When you create new Framework project, Xcode will ask you if you want to create new workspace and add that project to workspace. This is the best approach
Add both your project and Framework to the workspace
Select you project target -> General tab. Add Framework and Libraries (add your library here)
When you want to use code from your Library in swift file, import it using import 'LibTargetName'
You can take a more programatic approach by using SWM (Swift Modules): https://github.com/jankuca/swm
It is very similar to npm (node.js package manager) or bower (client-side module manager); you declare your dependencies in a swiftmodule.json file like below. It does not have a central module registry like the two mentioned JS solutions, it only accepts git URLs.
{
"name": "ProjectName",
"dependencies": {
"Dependency": "git://github.com/…/….git"
}
}
…run swm install and have the Dependency module (compiled into a *.swiftmodule binary) ready for import in the .modules/ directory.
import Dependency
And if you prefer to skip Xcode for app development, you can also build your whole app using swm build (more info in the project's readme).
The project is still in early stages but it makes itself useful a lot for me at least. It provides the most clean (and clear) way of creating importable modules.
Here is a video which is very straightforward: http://eonil-observatory.tumblr.com/post/117205738262/a-proper-way-to-add-a-subproject-to-another-xcode
The video is for OS X instead of iOS. But you will get it and figure out the process for iOS.
Let's assume that AppA needs to reused code from SharedProject.
The following process works for me in Xcode 7 Beta:
Create SharedProject. Project type must be Framework instead of Application. You write common code in this project and mark the code as public.
Open AppA in Xcode, open the folder which contains SharedProject in Finder. Drag the .xcodeproj file of SharedProject from Finder and drop it into the root folder of AppA in Xcode Project Navigator.
AppA --> Build Phases --> Link Binary with Libraries. Add SharedProject.
import SharedProject and reuse code from SharedProject!
Edit:
Nowadays I suggest you use Carthage. It's better than the home made solution above.
Base on this question
Why don't iOS framework dependencies need to be explicitly linked to a static library
I read the selected answer and still don't understand so I made an example project
Test Project on Github
In the test project, I remove all framework from Link Binary With Libraries and File navigation for both main project and the static library (including Foundation.framework and UIKit.framework too), basically, both project link to 0 frameworks.
Questions are
In static library, it's including MapKit/MapKit.h without referencing the Mapkit.framework to the project, why is its still working?
In main project, I remove UIKit.framework and Foundation.framework from the project, why is it still working?
Since it's working for now, will there be any issue later?
Thank you for your comment.
P.S. By working, I mean I can run on the simulator and I can archive the main project without any error.
Edit 25/07/2014
I tried with the real app that I'm working on, it's the same.
I highlight Foundation, UIKit, CoreData and 10 another frameworks in File Navigation, well, all of them.
Uncheck the target in Utilities Panel --> Target Membership
Build : Pass, Run : Pass
Every functionality of my app is still working as expected. I don't get this.
Check your project build settings. Underneath LLVM 5.1 — Language — Modules you should see the option 'Link Frameworks Automatically'. In your case it sounds like it's set to 'YES', the default.
In that case, instead of producing an error when you reference a class that the compiler doesn't know, it'll figure out which Framework contains that class and link it. In your code it'll be MKMapView or one of the other MapKit classes that triggers the linkage.
EDIT: from the relevant 'What's New?' document:
Auto Linking is enabled for frameworks imported by code modules. When
a source file includes a header from a framework that supports
modules, the compiler generates extra information in the object file
to automatically link in that framework. The result is that, in most
cases, you will not need to specify a separate list of the frameworks
to link with your target when you use a framework API that supports
modules.
Another way of looking at it is that the compiler is smart enough to mutate #import to #import when the framework has been built appropriately. All system frameworks have been.
To elaborate #Tommy's answer, a framework that supports modules satisfies the following 2 conditions:
Under Build Settings > Packaging
Define Modules is set to YES
Module Map File exists.
So, if you're certain that the framework you're using in your code modularizes like that, you can choose to not explicitly add it in the link phase as it will be automatically added as long as in the project file, under Apple Clang - Language - Modules, The option Link Frameworks Automatically is set to YES.