android - [Koin]: Instance creation error : could not create instance for

Question

I'm new in Koin and I've stuck with this error for a long time. This error is found when I run the code on emulator. I have no idea how to solve this. So, Do anyone have any suggestion?

E/[Koin]: Instance creation error : could not create instance for [Factory:'com.example.findgithubretrofit2rx.ui.SearchViewModel']: org.koin.core.error.NoBeanDefFoundException: No definition found for class:'com.example.findgithubretrofit2rx.data.UserImpl'. Check your definitions!
        org.koin.core.scope.Scope.throwDefinitionNotFound(Scope.kt:246)
        org.koin.core.scope.Scope.resolveInstance(Scope.kt:216)
        org.koin.core.scope.Scope.get(Scope.kt:181)
        com.example.findgithubretrofit2rx.di.ModulesKt$mainModule$1$1.invoke(Modules.kt:19)
        com.example.findgithubretrofit2rx.di.ModulesKt$mainModule$1$1.invoke(Unknown Source:4)
        org.koin.core.instance.InstanceFactory.create(InstanceFactory.kt:50)
        org.koin.core.instance.FactoryInstanceFactory.get(FactoryInstanceFactory.kt:36)
        org.koin.core.registry.InstanceRegistry.resolveInstance$koin_core(InstanceRegistry.kt:87)
        org.koin.core.scope.Scope.resolveInstance(Scope.kt:214)
        org.koin.core.scope.Scope.get(Scope.kt:181)
        org.koin.androidx.viewmodel.ViewModelFactoryKt$defaultViewModelFactory$1.create(ViewModelFactory.kt:50)
        androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:187)
        androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:150)
        org.koin.androidx.viewmodel.ViewModelResolutionKt.get(ViewModelResolution.kt:21)
        org.koin.androidx.viewmodel.ViewModelResolutionKt.resolveInstance(ViewModelResolution.kt:10)
        org.koin.androidx.viewmodel.scope.ScopeExtKt.getViewModel(ScopeExt.kt:70)
        org.koin.androidx.viewmodel.scope.ScopeExtKt.getViewModel(ScopeExt.kt:56)
        org.koin.androidx.viewmodel.koin.KoinExtKt.getViewModel(KoinExt.kt:34)
        org.koin.androidx.viewmodel.ext.android.ViewModelStoreOwnerExtKt.getViewModel(ViewModelStoreOwnerExt.kt:60)
        com.example.findgithubretrofit2rx.ui.SearchFragment$$special$$inlined$viewModel$1.invoke(ViewModelStoreOwnerExt.kt:45)
        com.example.findgithubretrofit2rx.ui.SearchFragment$$special$$inlined$viewModel$1.invoke(Unknown Source:0)
        kotlin.UnsafeLazyImpl.getValue(Lazy.kt:81)
        com.example.findgithubretrofit2rx.ui.SearchFragment.getVm(Unknown Source:2)
        com.example.findgithubretrofit2rx.ui.SearchFragment.observeLiveDate(SearchFragment.kt:45)
        com.example.findgithubretrofit2rx.ui.SearchFragment.onViewCreated(SearchFragment.kt:41)
        androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:322)
        androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1185)
        androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1354)
        androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1432)
        androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1495)
        androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2617)
        androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2569)
        androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:247)
        androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:541)
        androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:210)
        android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1334)
        android.app.Activity.performStart(Activity.java:7029)
        android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2741)
        android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
        android.app.ActivityThread.-wrap11(Unknown Source:0)
        android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
        android.os.Handler.dispatchMessage(Handler.java:106)
        android.os.Looper.loop(Looper.java:164)
        android.app.ActivityThread.main(ActivityThread.java:6494)
        java.lang.reflect.Method.invoke(Native Method)
        com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
        com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.findgithubretrofit2rx, PID: 30918
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.findgithubretrofit2rx/com.example.findgithubretrofit2rx.ui.MainActivity}: org.koin.core.error.InstanceCreationException: Could not create instance for [Factory:'com.example.findgithubretrofit2rx.ui.SearchViewModel']
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6494)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
     Caused by: org.koin.core.error.InstanceCreationException: Could not create instance for [Factory:'com.example.findgithubretrofit2rx.ui.SearchViewModel']
        at org.koin.core.instance.InstanceFactory.create(InstanceFactory.kt:59)
        at org.koin.core.instance.FactoryInstanceFactory.get(FactoryInstanceFactory.kt:36)
        at org.koin.core.registry.InstanceRegistry.resolveInstance$koin_core(InstanceRegistry.kt:87)
        at org.koin.core.scope.Scope.resolveInstance(Scope.kt:214)
        at org.koin.core.scope.Scope.get(Scope.kt:181)
        at org.koin.androidx.viewmodel.ViewModelFactoryKt$defaultViewModelFactory$1.create(ViewModelFactory.kt:50)
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:187)
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:150)
        at org.koin.androidx.viewmodel.ViewModelResolutionKt.get(ViewModelResolution.kt:21)
        at org.koin.androidx.viewmodel.ViewModelResolutionKt.resolveInstance(ViewModelResolution.kt:10)
        at org.koin.androidx.viewmodel.scope.ScopeExtKt.getViewModel(ScopeExt.kt:70)
        at org.koin.androidx.viewmodel.scope.ScopeExtKt.getViewModel(ScopeExt.kt:56)
        at org.koin.androidx.viewmodel.koin.KoinExtKt.getViewModel(KoinExt.kt:34)
        at org.koin.androidx.viewmodel.ext.android.ViewModelStoreOwnerExtKt.getViewModel(ViewModelStoreOwnerExt.kt:60)
        at com.example.findgithubretrofit2rx.ui.SearchFragment$$special$$inlined$viewModel$1.invoke(ViewModelStoreOwnerExt.kt:45)
        at com.example.findgithubretrofit2rx.ui.SearchFragment$$special$$inlined$viewModel$1.invoke(Unknown Source:0)
        at kotlin.UnsafeLazyImpl.getValue(Lazy.kt:81)
        at com.example.findgithubretrofit2rx.ui.SearchFragment.getVm(Unknown Source:2)
        at com.example.findgithubretrofit2rx.ui.SearchFragment.observeLiveDate(SearchFragment.kt:45)
        at com.example.findgithubretrofit2rx.ui.SearchFragment.onViewCreated(SearchFragment.kt:41)
        at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:322)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1185)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1354)
        at androidx.fragment.app.FragmentManager.moveFragmentToExpectedState(FragmentManager.java:1432)
        at androidx.fragment.app.FragmentManager.moveToState(FragmentManager.java:1495)
        at androidx.fragment.app.FragmentManager.dispatchStateChange(FragmentManager.java:2617)
        at androidx.fragment.app.FragmentManager.dispatchActivityCreated(FragmentManager.java:2569)
        at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:247)
        at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:541)
        at androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:210)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1334)
        at android.app.Activity.performStart(Activity.java:7029)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2741)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)?
        at android.app.ActivityThread.-wrap11(Unknown Source:0)?
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)?
        at android.os.Handler.dispatchMessage(Handler.java:106)?
        at android.os.Looper.loop(Looper.java:164)?
        at android.app.ActivityThread.main(ActivityThread.java:6494)?
        at java.lang.reflect.Method.invoke(Native Method)?
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)?
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)?
E/AndroidRuntime: Caused by: org.koin.core.error.NoBeanDefFoundException: No definition found for class:'com.example.findgithubretrofit2rx.data.UserImpl'. Check your definitions!
        at org.koin.core.scope.Scope.throwDefinitionNotFound(Scope.kt:246)
        at org.koin.core.scope.Scope.resolveInstance(Scope.kt:216)
        at org.koin.core.scope.Scope.get(Scope.kt:181)
        at com.example.findgithubretrofit2rx.di.ModulesKt$mainModule$1$1.invoke(Modules.kt:19)
        at com.example.findgithubretrofit2rx.di.ModulesKt$mainModule$1$1.invoke(Unknown Source:4)
        at org.koin.core.instance.InstanceFactory.create(InstanceFactory.kt:50)
            ... 41 more

Here, there're classes that I think its cause the error. SearchFragment.kt , SearchViewModel.kt, UserImpl.kt, RetrofitBuilder.kt

class SearchFragment : Fragment() {

    private val vm: SearchViewModel by viewModel()
    .....
    .......

class SearchViewModel(private val userImpl: UserImpl) : ViewModel() {

    private val disposable = CompositeDisposable()
    ....
    ......

class UserImpl(private val gitHubApi: GitHubApi) : UserRepository {

    override fun getSearchUser(str: String?): Observable<SearchUserResponse> {
        return gitHubApi.searchUsers(str)
    }
}

interface UserRepository {

    fun getSearchUser(str: String?): Observable<SearchUserResponse>
}

class RetrofitBuilder(val okHttpClient: OkHttpClient,
                      val converterFactory: Converter.Factory,
                      val adapterFactory: CallAdapter.Factory) {

    inline fun <reified T> build(baseUrl: String): T {
        return Retrofit.Builder()
            .client(okHttpClient)
            .baseUrl(baseUrl)
            .addConverterFactory(converterFactory)
            .addCallAdapterFactory(adapterFactory)
            .build()
            .create(T::class.java)
    }
}

This is my modules.

val appModule = module {

    factory<UserRepository> { UserImpl(get()) }

    viewModel { SearchViewModel(get())}
}

val networkModule = module {
    single {
        HttpLoggingInterceptor().apply {
            this.level = HttpLoggingInterceptor.Level.BODY
        }
    }

    single {
        object : Interceptor {
            @Throws(IOException::class)
            override fun intercept(chain: Interceptor.Chain): Response {
                val original: Request = chain.request()
                val o

Answer 1

I think the problem is the in the names.

in app module you are creating instance for UserRepository

val appModule = module {

    factory<UserRepository> { UserImpl(get()) }

    viewModel { SearchViewModel(get())}
}

And in viewModel you are adding UserImpl

class SearchViewModel(private val userImpl: UserImpl)

Koin needs to know the same parameter that you are adding, even if it is an interface. But as a lot of websites recommends to build your software with abstractions instead of implementations, So with that in mind :). you should UserImpl in viewModel, try to add UserRepository interface.

class SearchViewModel(private val userRepository: UserRepository)