Koin 注入到 viewModels android答案

【问题标题】：Koin inject to viewModels androidKoin 注入到 viewModels android
【发布时间】：2020-08-13 16:08:33
【问题描述】：

我决定从 Dagger 切换到 Koin，因为它更轻量级且代码更少。所以我的模块就是这样的

val databaseModule = module {

   single {
        get<AppDatabase>().serverDao()
    }
   
    // And all the DAOs here
}

val repositoryModule = module {

   single<ServerRepository> {
        // ServerDao, AccountDao, ApiManager
        return@single ServerRepositoryImpl(get(), get(), get())
    }

    // And all the repositories here

}

val networkModule = module {
    single<Gson> {
        val gsonBuilder = GsonBuilder()
        return@single gsonBuilder.setLenient().create()
    }

    single {
        if (!BuildConfig.DEBUG) return@single null

        val httpLoggingInterceptor = HttpLoggingInterceptor()
        httpLoggingInterceptor.level = HttpLoggingInterceptor.Level.BODY
        return@single httpLoggingInterceptor
    }

    single {
        return@single HeaderInterceptor()
    }

    single {
        return@single BaseUrlHolder(BuildConfig.BASE_HOLDER_URL)
    }

    single {
        val loggingInterceptor = get<Interceptor?>()
        OkHttpClient().newBuilder().apply {
            connectTimeout(60, TimeUnit.SECONDS)
            readTimeout(60, TimeUnit.SECONDS)
            writeTimeout(60, TimeUnit.SECONDS)
            loggingInterceptor?.let {
                addInterceptor(it)
            }
            addInterceptor(get<HeaderInterceptor>())
        }.also {
            return@single it.build()
        }
    }

    single<Retrofit> {
        return@single Retrofit.Builder()
            .addCallAdapterFactory(CoroutineCallAdapterFactory())
            .addConverterFactory(GsonConverterFactory.create(get()))
            .client(get<OkHttpClient>())
            .build()
    }

    single<MyApiService> {
        return@single get<Retrofit>().create(MyApiService::class.java)
    }
}

val managersModule = module {
    single<ApiManager> {

        // I have to provide the URL runTime because it is not standar
        //  private val baseUrlHolder: BaseUrlHolder,
        //  private val retrofitBuilder: Retrofit.Builder
        return@single ApiManagerImpl(get(), get())
    }

所以在我的 SplashView 中，我想要拥有 ServerRepository 和 ApiManager。我试图让他们通过 KoinComponent 但没有

   // *****BaseViewModel implements KoinComponent*****
   class SplashViewModel : BaseViewModel() {

      // Here i should get the serverRepository.
      private val serverRepository: ServerRepository by inject()
      ......

   }

在 SplashActivity 中，我将视图模型设为

private val splashViewModel: SplashViewModel by viewModels()

我总是遇到同样的错误

 Caused by: org.koin.core.error.NoBeanDefFoundException: No definition found for class:'retrofit2.Retrofit$Builder'. Check your definitions!

【问题讨论】：

标签： android kotlin retrofit2 koin

【解决方案1】：

必须定义 ViewModel 的 Bean 定义

val viewModelModule = module {
     viewModel {
         SplashViewModel() // if there are no parameter otherwise use get() function to pass the parameter of the viewmodel 
     }  
}

【讨论】：

不...同样的问题。我认为错误出在networkModule上。它说没有找到类的定义：'retrofit2.Retrofit$Builder'

【解决方案2】：

解决办法是我没有正确编写networkModule

single<OkHttpClient> {
        val loggingInterceptor = get<Interceptor?>()
        val httpClientBuilder = OkHttpClient().newBuilder().apply {
            connectTimeout(60, TimeUnit.SECONDS)
            readTimeout(60, TimeUnit.SECONDS)
            writeTimeout(60, TimeUnit.SECONDS)
            addInterceptor(get<HeaderInterceptor>())
            loggingInterceptor?.let {
                addInterceptor(loggingInterceptor)
            }
        }
        return@single httpClientBuilder.build()
    }

    single<Retrofit.Builder> {
        return@single Retrofit.Builder()
            .addCallAdapterFactory(CoroutineCallAdapterFactory())
            .addConverterFactory(GsonConverterFactory.create(get()))
            .client(get<OkHttpClient>())
    }

【讨论】：

【解决方案3】：

这里你问Retrofit.Builder的一个实例

val managersModule = module {
    single<ApiManager> {

        // I have to provide the URL runTime because it is not standar
        //  private val baseUrlHolder: BaseUrlHolder,
        //  private val retrofitBuilder: Retrofit.Builder
        return@single ApiManagerImpl(get(), get())
    }

在依赖图中，您只提供Retrofit 而不是Retrofit.Builder

以下几行的更改可能会解决这种情况：

single<Retrofit.Builder> { // change type
        return@single Retrofit.Builder()
            .addCallAdapterFactory(CoroutineCallAdapterFactory())
            .addConverterFactory(GsonConverterFactory.create(get()))
            .client(get<OkHttpClient>())
            // Remove
            //.build()
    }

single<MyApiService> {
        // adjustment
        return@single get<Retrofit.Builder>().build().create(MyApiService::class.java)
    }

【讨论】：