Hello :wave: I am trying to use a cocoapod in our multi module KM Project. I have all bindings showi...

# kotlin-native

[Dmitriy Tarasevich]

Hello 👋
I am trying to use a cocoapod in our multi module KM Project. I have all bindings showing up, but am two experiencing two seperate issues during compile time.

1. It seems as though the assemble<ProjectName>RelaseXCFramework does not automatically link the cocoapod frameworks into the build. for each architecture i have to manually specify the libraries cocoapod location using

linkerOpts("-F$frameworkPath")
                        linkerOpts("-rpath", frameworkPath)
                        linkerOpts("-framework", "<Library>"

Once i do this, i can get a successful build, but a failure once i utilize the framework in my project with the following errror

dyld[32068]: Library not loaded: <FrameworkClass>

I feel like I have an incorrect setting as no where in docs is it stated that i have to manually link cocoapod frameworks. Any suggestions?

[Landry Norris]

Can you share what the Cocoapod is? Keep in mind that if it is a Swift Cocoapod, you can only call into objc annotated methods and classes.

[Landry Norris]

Also, check <module>/build/cocoapods/defs/<podName>.def, which should be created during the build process. This is the generated def file.

[Dmitriy Tarasevich]

It's launch darkly.

[Dmitriy Tarasevich]

I'll get a link in a few. Afk atm

[Landry Norris]

https://github.com/CocoaPods/Specs/blob/master/Specs/f/0/6/LaunchDarkly/8.0.0/LaunchDarkly.podspec.json
I’m at work right now, so I’ve only glanced at it, but it looks like there is Objective-C support. Are you using the cocoapods Kotlin plugin and adding it to the cocoapods block?

[Dmitriy Tarasevich]

Yup. I'll get ya a snippet.

[Dmitriy Tarasevich]

The IDE picks up all the bindings

[Dmitriy Tarasevich]

And I have it compiling too now

[Dmitriy Tarasevich]

kotlin {

    cocoapods {
        ios.deploymentTarget = "13.5"

        summary = "CocoaPods Library"
        homepage = "<https://github.com/JetBrains/kotlin>"

        pod("LaunchDarkly") {
            version = "~> 8.0"
        }
    }
}

[Landry Norris]

You said you got it compiling now. Did you fix the issue?

[Dmitriy Tarasevich]

nope, the xcframework compiles succesfully but when i open the iOS app with the framework I get

dyld[32068]: Library not loaded: <FrameworkClass>

[Dmitriy Tarasevich]

FrameworkClass is actually like LDClient which is a launch darkly class

[Landry Norris]

Go into XCode and check the build phases tab.

[Landry Norris]

Under ‘Link Binary with Libraries’, there’s a plus button. Click it and search for the framework it says is missing.

[Dmitriy Tarasevich]

shouldn't the framework from launch darkly be baked into the framework that i created from my KM project?

[Dmitriy Tarasevich]

or is that not how it works

[Landry Norris]

Depends on if it’s static or dynamic. I think Apple’s wanting people to lean towards dynamic frameworks now.

[Dmitriy Tarasevich]

i believe its dynamic

[Landry Norris]

When you link a static framework, it builds it into your binary. When you link a dynamic framework, it just creates stubs (you can check by running ‘nm -C | grep <some method in the library>’ and checking the second column (I want to say ‘U’ means dynamically linked)). If you link against a dynamic library, it has to be present on the system when your app starts.

[Dmitriy Tarasevich]

interesting, makes sense. Should i be able to just point my iOS app to use launch darkly through cocoapods?

[Landry Norris]

You can tell XCode to bundle the binary in with your app.

[Landry Norris]

I think you still have to tell XCode to include the binary. I think that’s what the ‘link binary with libraries’ section of ‘Build Phases’ is for. You have to do this for native iOS development too, I believe.

[Dmitriy Tarasevich]

alright. well this gives a bunch to go on. I unfortunately had to switch branches to continue work on something else. But ill try out your suggestions today.

[Dmitriy Tarasevich]

one other thing.

[Landry Norris]

Looking at my project using cocoapods, there’s something at the end of ‘Build Phases’ called ‘[CP] Embed Pods Framework’ that calls a script. Looks like that script is what does it.

[Dmitriy Tarasevich]

in order for me to get the framework compiled. I have to manually specify the framework for each architecture in the binaries setup using

val armFramework = "${parent!!.rootDir.absolutePath}/integrations/integration-launch-darkly/build/cocoapods/synthetic/IOS/build/Release-iphoneos/LaunchDarkly"
                        val frameworkPath = x86Framework
                        linkerOpts("-F$frameworkPath")
                        linkerOpts("-rpath", frameworkPath)
                        linkerOpts("-framework", "LaunchDarkly")

[Dmitriy Tarasevich]

your cocoapod project being your iOS app?

[Landry Norris]

Yes. An app that uses cocoapods in it. Fixed the wording.

[Dmitriy Tarasevich]

interesting, im worried about all the issues im going to go through getting this working on CI lol

[Dmitriy Tarasevich]

without writing a similar script i suppose

[Landry Norris]

I think the kotlin multiplatform plugin creates the script.

[Landry Norris]

Here’s the script I see.
"${PODS_ROOT}/Target Support Files/Pods-app-ios/Pods-app-ios-frameworks.sh"

[Landry Norris]

This requires me to run a syncFramework gradle task once before I can build via XCode (but only once until I clean the project).

[Dmitriy Tarasevich]

ohh so i see this in the .podspec file generated right?

[Landry Norris]

I think so. If I remember correctly, when you add the pod via XCode it sets this up.

[Dmitriy Tarasevich]

and this is assuming who ever is consuming this library also has the KM project locally

[Landry Norris]

They’ll have to add LaunchDarkly to their Podfile from what I remember. I don’t think KMM can tell a consumer of a library to set up cocoapods automatically yet.

[Dmitriy Tarasevich]

alright, I wish this was a bit more documented some where. I appreciate all your help

[Landry Norris]

Cocoapods in general are a bit iffy at times. It would be nice if JB were to add swift package support to the KMM plugin (even if only for Objective-C bindings).

[Dmitriy Tarasevich]

all in good time i hope