Android Dagger 2一些构造函数无法注入ViewModel

Question

I want to Inject my Room Repositories and Rest Repositories into my ViewModel class. However, I can inject rest repository but, when I try to inject room repository, it gives error.

class RestRepository @Inject constructor(private val restService: RestService) {
    fun register(username: String, password: String, email: String): Single<NormalResponse> {
        return restService.register(username, password, email)
    }

    fun createAuthToken(username: String, password: String): Single<TokenResponse> {
        return restService.createAuthToken(username, password)
    }
}

class MessageRepository @Inject constructor(private val messageDao: MessageDao) {
    val all: List<Message> get() = messageDao.getAll

    fun insert(vararg messages: Message) {
        messageDao.insert(*messages)
    }

    fun update(message: Message) {
        messageDao.update(message)
    }

    fun delete(message: Message) {
        messageDao.delete(message)
    }
}

@Module
class RestModule {
    @Provides
    internal fun provideRetrofit(): Retrofit {
        return Retrofit.Builder()
                .baseUrl(Constants.BASE_URL)
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .addConverterFactory(GsonConverterFactory.create())
                .build()
    }

    @Provides
    internal fun provideService(retrofit: Retrofit): RestService {
        return retrofit.create<RestService>(RestService::class.java)
    }

    @Provides
    internal fun provideRepository(restService: RestService): RestRepository {
        return RestRepository(restService)
    }
}

@Module(includes = [ApplicationModule::class])
class RoomModule {
    @Provides
    internal fun provideRoomDatabase(context: Context): AppDatabase {
        return AppDatabase.getAppDatabase(context)
    }

    @Provides
    internal fun provideMessageDao(appDatabase: AppDatabase): MessageDao {
        return appDatabase.messageDao()
    }

    @Provides
    internal fun provideMessageRepository(messageDao: MessageDao): MessageRepository {
        return MessageRepository(messageDao)
    }
}

@Module
abstract class MainFragmentBindingModule {
    @ContributesAndroidInjector(modules = [ApplicationModule::class, UtilsModule::class, RestModule::class, RoomModule::class])
    internal abstract fun provideChatFragmentFactory(): ChatFragment
}

class ChatViewModel @Inject constructor(val restRepository: RestRepository, val messageRepository: MessageRepository) : ViewModel() {

}

And error is like that:

error: [dagger.android.AndroidInjector.inject(T)] me.ibrahimsn.capsules.data.local.message.MessageDao cannot be provided without an @Provides-annotated method.

Edit: Solution https://stackoverflow.com/a/51783147/10203775

Answer 1

I fixed the problem, thanks..

@Module(includes = [(ViewModelModule::class)])
class ApplicationModule {

    @Provides
    @Singleton
    internal fun provideRetrofit(): Retrofit {
        return Retrofit.Builder()
                .baseUrl(Constants.BASE_URL)
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .addConverterFactory(GsonConverterFactory.create())
                .build()
    }

    @Provides
    @Singleton
    internal fun provideRetrofitService(retrofit: Retrofit): RestService {
        return retrofit.create<RestService>(RestService::class.java)
    }

    @Provides
    @Singleton
    internal fun provideRoomDatabase(app: Application): AppDatabase {
        return AppDatabase.getAppDatabase(app)
    }

    @Provides
    @Singleton
    internal fun provideMessageDao(appDatabase: AppDatabase): MessageDao {
        return appDatabase.messageDao()
    }
}

@Singleton
class MessageRepository @Inject constructor(private val messageDao: MessageDao) {

    val all: List<Message> get() = messageDao.getAll

    fun insert(vararg messages: Message) {
        messageDao.insert(*messages)
    }

    fun update(message: Message) {
        messageDao.update(message)
    }

    fun delete(message: Message) {
        messageDao.delete(message)
    }
}