Hi :wave: , I have a kotlin function (in a KMP mod...

# touchlab-tools

[Francesco Pedron]

Hi 👋 , I have a kotlin function (in a KMP module with SKIE plugin applied) that has this signature:

suspend fun onDataReceived(data: ByteArray)

that is translated to this swift signature

func onDataReceived(data: Skie.Stdlib.ByteArray.__Kotlin) async throws

How should I convert a swift [UInt8] to a Skie.Stdlib.ByteArray?
Thanks

[Filip Dolník]

Hi! The Skie.Stdlib.ByteArray.__Kotlin is just a typealias to the Kotlin ByteArray, so the conversion works the same as without SKIE.

[Francesco Pedron]

Ok thanks. Will try again with your input.

[Francesco Pedron]

Posting here a link to some code that converts from Swift's Data to Kotlin's ByteArray (KotlinByteArray) if anyone encounters the same problem I had: https://stackoverflow.com/a/72865245/14999651

[Darron Schall]

Here's another option:

Use this extension in Swift to convert [UInt8] to `Data`:

extension Array where Element == UInt8 {
    var data: Data {
        return Data(self)
    }
}

Use this Kotlin helper to convert NSData to Kotlin `ByteArray`:

// Create in file named NSDataExtensions.kt
@OptIn(ExperimentalForeignApi::class)
fun NSData.toByteArray() = ByteArray(length.toInt()).apply {
    usePinned {
        memcpy(it.addressOf(0), bytes, length)
    }
}

Then, in your Swift code, usage is:

let bytes: [UInt8] = [2, 1, 3, 5]
let kotlinByteArray = NSDataExtensionsKt.toByteArray(bytes.data)