Another way of injecting classes to swift side with koin

[osrl]

Hi, first of all, thanks for the repo. I've already shared this with you before but I just wanted to add this here for reference to other people:

here is how I use koin from swift side:

Koin.swift

typealias KoinApplication = Koin_coreKoinApplication
typealias Koin = Koin_coreKoin


extension KoinApplication {
    static let shared = KoinIOSKt.doInitKoinIos(doOnStartup: {
        print("Koin started")
    }, appDeclaration: { app in
        app.properties(values: ["BASE_URL":  "exampleapi.com"]) //you can inject any primitive to koin initiation
    })

  @discardableResult
  static func start() -> KoinApplication {
    shared
  }
}

// Helper function to inject any kotlin class. it will be like by inject()
func inject<T : AnyObject>() -> T {
    return KoinApplication.shared.koin.get(objCClass: T.self) as! T
}

// Helper function to inject any kotlin class with parameter. 
func inject<T : AnyObject>(param: Any?) -> T {
    return KoinApplication.shared.koin.get(objCClass: T.self, parameter: param) as! T
}

// Koin scoping features
func inject<T : AnyObject>(scope: String) -> T {
    let scope = getScope(named: scope)
    return scope.get(objCClass: T.self) as! T
}

// Koin scoping features
func inject<T : AnyObject>(scope: String, linkTo otherScope: String) -> T {
    let scope = getScope(named: scope)
    let otherScope = getScope(named: otherScope)
    let array = KotlinArray(size: 1, init: { _ in otherScope })
    scope.linkTo(scopes: array)
    return scope.get(objCClass: T.self) as! T
}

KoinIOS.kt (iOS Main target)

@Suppress("unused")
fun initKoinIos(
    doOnStartup: () -> Unit,
    appDeclaration: KoinAppDeclaration
): KoinApplication {
    val koin = initKoin {
        module {
            single { doOnStartup }
        }
        appDeclaration()
    }

    setCrashlyticsUnhandledExceptionHook()

    return koin
}


// this currently supports single parameter but it should be easy to implement for more parameters
fun Koin.get(objCClass: ObjCClass, parameter: Any?): Any {
    val kClazz = getOriginalKotlinClass(objCClass)!!
    return get(kClazz) { parametersOf(parameter) }
}

fun Koin.get(objCClass: ObjCClass): Any {
    val kClazz = getOriginalKotlinClass(objCClass)!!
    return get(kClazz)
}

fun Koin.get(objCProtocol: ObjCProtocol): Any {
    val kClazz = getOriginalKotlinClass(objCProtocol)!!
    return get(kClazz)
}

ContentView.swift

// ObservedViewModel is from KMP-ObservableViewModel library. You can inject any class, or any viewmodel.
@ObservedViewModel private var myViewModel: MyViewModel = inject()

This can even be improved with a property wrapper

@propertyWrapper
struct Inject<T : AnyObject> {
    lazy var wrappedValue: T = { inject() }()

    init() { }
}

@Inject private var myViewModel: MyViewModel

I couldn't find a way to use the property wrapper with @ObservedViewModel though. So I'm using normal property initializer with inject() for my ViewModels.

[frankois944]

Hi, first of all, thanks for the repo. I've already shared this with you before but I just wanted to add this here for reference to other people:

Thanks for your feedback,
Yes, I remember, you gave me the idea of the propertyWrapper.

And I think, extending the Koin_coreKoinApplication to store the main Koin context is a good idea.

[osrl]

I saw your implementation just now. Great improvements. Loved it.

[osrl]

By the way,
I needed some scoping features of koin so I've added new functions to the original post here.

[frankois944]

Thanks,
I didn't implement scope capabilities as it will add more complexity in the playground, which I don't want.
Also, I just want to create a wrapper Swift -> Kotlin/Koin with no more customization.