我尝试使用带有DI的MVVM +存储库模式创建注册,我使用@ViewModelInject,一切都很好,但是现在不赞成使用@ViewModelInject,我将@ViewModelInject更改为@HiltViewModel + @Inject Constructor()并面对了error: [Dagger/MissingBinding] *.AuthRepository cannot be provided without an @Provides-annotated method.我试图在接口(interface)中为注册函数添加@Provides批注,但遇到另一个错误


AuthViewModel

    @HiltViewModel
    class AuthViewModel @Inject constructor(
        private val repository: AuthRepository,
        private val applicationContext: Context,
        private val dispatcher: CoroutineDispatcher = Dispatchers.Main
    ) : ViewModel() {
private val _registerStatus = MutableLiveData<Event<Resource<AuthResult>>>()
    val registerStatus: LiveData<Event<Resource<AuthResult>>> = _registerStatus

    private val _loginStatus = MutableLiveData<Event<Resource<AuthResult>>>()
    val loginStatus: LiveData<Event<Resource<AuthResult>>> = _loginStatus

    fun login(email: String, password: String) {
        if(email.isEmpty() || password.isEmpty()) {
            val error = applicationContext.getString(R.string.error_input_empty)
            _loginStatus.postValue(Event(Resource.Error(error)))
        } else {
            _loginStatus.postValue(Event(Resource.Loading()))
            viewModelScope.launch(dispatcher) {
                val result = repository.login(email, password)
                _loginStatus.postValue(Event(result))
            }
        }
    }

    fun register(email: String, username: String, password: String, repeatedPassword: String) {
        val error = if(email.isEmpty() || username.isEmpty() || password.isEmpty()) {
            applicationContext.getString(R.string.error_input_empty)
        } else if(password != repeatedPassword) {
            applicationContext.getString(R.string.error_incorrectly_repeated_password)
        } else if(username.length < MIN_USERNAME_LENGTH) {
            applicationContext.getString(R.string.error_username_too_short, MIN_USERNAME_LENGTH)
        } else if(username.length > MAX_USERNAME_LENGTH) {
            applicationContext.getString(R.string.error_username_too_long, MAX_USERNAME_LENGTH)
        } else if(password.length < MIN_PASSWORD_LENGTH) {
            applicationContext.getString(R.string.error_password_too_short, MIN_PASSWORD_LENGTH)
        } else if(!Patterns.EMAIL_ADDRESS.matcher(email).matches()) {
            applicationContext.getString(R.string.error_not_a_valid_email)
        } else null

        error?.let {
            _registerStatus.postValue(Event(Resource.Error(it)))
            return
        }
        _registerStatus.postValue(Event(Resource.Loading()))
        viewModelScope.launch(dispatcher) {
            val result = repository.register(email, username, password)
            _registerStatus.postValue(Event(result))
        }
    }
}
应用模块
@Module
@InstallIn(SingletonComponent::class)
object AppModule {

    @Singleton
    @Provides
    fun provideMainDispatcher() = Dispatchers.Main as CoroutineDispatcher

    @Singleton
    @Provides
    fun provideApplicationContext(@ApplicationContext context: Context) = context

    @Singleton
    @Provides
    fun provideGlideInstance(@ApplicationContext context: Context) =
        Glide.with(context).setDefaultRequestOptions(
            RequestOptions()
                .placeholder(R.drawable.ic_image)
                .error(R.drawable.ic_error)
                .diskCacheStrategy(DiskCacheStrategy.DATA)
        )
}
认证模块
@Module
@InstallIn(ActivityComponent::class)
object AuthModule {

    @ActivityScoped
    @Provides
    fun provideAuthRepository() = DefaultAuthRepository() as AuthRepository

}
AuthRepository
interface AuthRepository {

    suspend fun register(email: String, username: String, password: String): Resource<AuthResult>

    suspend fun login(email: String, password: String): Resource<AuthResult>
}
DefaultAuthRepository
class DefaultAuthRepository : AuthRepository {

    val auth = FirebaseAuth.getInstance()
    val users = FirebaseFirestore.getInstance().collection("users")


    override suspend fun register(
        email: String,
        username: String,
        password: String
    ): Resource<AuthResult> {
        return withContext(Dispatchers.IO) {
            safeCall {
                val result = auth.createUserWithEmailAndPassword(email, password).await()
                val uid = result.user?.uid!!
                val user = User(uid, username)
                users.document(uid).set(user).await()
                Resource.Success(result)
            }
        }
    }

    override suspend fun login(email: String, password: String): Resource<AuthResult> {
        TODO("Not yet implemented")
    }
}

//Dagger - Hilt
    implementation 'com.google.dagger:hilt-android:2.31.2-alpha'
    kapt 'com.google.dagger:hilt-android-compiler:2.31.2-alpha'
    implementation 'androidx.hilt:hilt-lifecycle-viewmodel:1.0.0-alpha03'
    kapt 'androidx.hilt:hilt-compiler:1.0.0-alpha03'
enter image description here

最佳答案

@Module
@InstallIn(ActivityComponent::class)
abstract class AuthModule{

    @Binds
    abstract fun bindAuthRepository(impl: DefaultAuthRepository): AuthRepository
}

关于android - 如果没有@Provides注释的方法,则无法提供: [Dagger/MissingBinding] *. AuthRepository错误,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/65996165/

10-10 20:55