Vectorform Kotlin Multiplatform Mobile (KMM) Example

This is a small example of using KMM using KTOR and a jokes API. This example does not demonstrate expect/actual classes that some projects may prefer to use for platform specific implementations.

Setup

Make sure org.gradle.java.home is set properly in gradle.properties.

e.g. org.gradle.java.home=/Library/Java/JavaVirtualMachines/adoptopenjdk-11.jdk/Contents/Home

Shared

The shared code for both iOS and Android is located in the shared directory. Use commonMain for code that each platform can share. Use the respective platform directories for any platform specific code.

class JokeAPI {

    private val client = HttpClient {
        install(JsonFeature) {
            serializer = KotlinxSerializer()
        }
    }

    suspend fun getJoke(): Joke {
        val url = BASE_URL
        val result = client.get<String>(url)
        return Json.decodeFromString(result)
    }

    companion object {
        private const val BASE_URL = "https://v2.jokeapi.dev/joke/Any?safe-mode"
    }
}

Android App

The Android application is located inside the androidApp directory. You can open this folder in Android Studio and run it as you would any Android Studio project.

suspend fun getJoke() {
    try {
        setContentString("getting joke...")
        val jokeAPI = JokeAPI()
        val joke = jokeAPI.getJoke()
        withContext(Dispatchers.Main) { setContentString(joke.toString()) }
    } catch (exception: Exception) {
        withContext(Dispatchers.Main) { handleException(exception) }
    }
}

iOS App

The iOS application is located inside the iosApp directory. You can open this folder in Xcode and run it as you would any Xcode project.

KMM generates the shared functions in iOS with a completion handler, or you can use the async function if your app's iOS version supports it.

func getJoke() {
    let jokeAPI: JokeAPI = JokeAPI()
    resultLabel.text = "getting joke..."
    jokeAPI.getJoke { [weak self] joke, error in
        self?.resultLabel.text = joke?.debugDescription
    }
}

Gradle

The gradle.kts file in the shared directory is the gradle file you should use for publishing frameworks and .aars. Run ./gradlew publish to push to your maven repo.

Cocoapods

For cocoapods, modify the shared.podspec file in root. After you commit, be sure to tag the release making sure it matches your podspec version.

Building Libraries

To build the iOS Frameworks and Android .aar's, run ./gradlew assemble

iOS Frameworks output = shared/build/bin

Android .aar output = shared/outputs/aar

License

MIT