如何注入泛型类型？Hilt泛型仓库依赖注入报错问题

问题背景 #

泛型仓库接口与实现 #

定义泛型仓库接口AuthRepo<R>：

interface AuthRepo<R> {
    val isUserAuthenticatedInFirebase: Boolean
    suspend fun oneTapSignInWithGoogle(): R
    suspend fun firebaseSignInWithGoogle(): R
}

实现类AuthRepoImpl，依赖注入两个命名的BeginSignInResult实例：

@Singleton
class AuthRepoImpl @Inject constructor(
   ...
   @Named(SING_IN_RESULT)
   private val singInResult: BeginSignInResult,
   @Named(SING_UP_RESULT)
   private val singUpResult: BeginSignInResult,
   ...
) : AuthRepo<BeginSignInResult>

Hilt绑定模块 #

通过AuthModule绑定仓库实现：

@Module
@InstallIn(ViewModelComponent::class)
abstract class AuthModule {
    @Binds
    abstract fun provideAuthRepository(
        authRepoImpl: AuthRepoImpl
    ): AuthRepo<BeginSignInResult>
}

非自定义类的注入逻辑 #

由于BeginSignInResult是非自定义类，通过挂起函数提供实例：

@Provides
@Named(AuthConstant.SING_IN_RESULT)
suspend fun provideSingInResult(
    oneTapClient: SignInClient,
    @Named(AuthConstant.SIGN_IN_REQUEST)
    signUpRequest: BeginSignInRequest
) : BeginSignInResult {
    return oneTapClient.beginSignIn(signUpRequest).await()
}

@Provides
@Named(AuthConstant.SING_UP_RESULT)
suspend fun provideSingUpResult(...) : BeginSignInResult ...

编译错误信息 #

com...AuthRepo<com...BeginSignInResult> cannot be provided without an @Provides-annotated method.
com...AuthRepo<com..BeginSignInResult> is injected at
com...OneTapSingInUseCase(authRepo)
com...OneTapSingInUseCase<com...BeginSignInResult> is injected at
com...AuthRepo<com....BeginSignInResult> is injected at
com...OneTapSingInUseCase(authRepo)
com...OneTapSingInUseCase<com...BeginSignInResult> is injected at
com...LoginViewModel(�, oneTapUseCase)
com...LoginViewModel is injected at
com...LoginViewModel_HiltModules.BindsModule.binds(arg0)
@dagger.hilt.android.internal.lifecycle.HiltViewModelMap java.util.Map<java.lang.String,javax.inject.Provider<androidx.lifecycle.ViewModel>> is requested at
dagger.hilt.android.internal.lifecycle.HiltViewModelFactory.ViewModelFactoriesEntryPoint.getHiltViewModelMap() [com....App_HiltComponents.SingletonC ? com...App_HiltComponents.ActivityRetainedC ? com...App_HiltComponents.ViewModelC]

解决方案 #

1. 修复组件作用域不匹配问题 #

AuthRepoImpl标注了@Singleton（归属SingletonComponent），但绑定它的AuthModule安装在ViewModelComponent，作用域不兼容导致Hilt无法解析依赖。

修复方式二选一：

• 将AuthModule的@InstallIn改为SingletonComponent：

  @Module
  @InstallIn(SingletonComponent::class)
  abstract class AuthModule {
      @Binds
      abstract fun provideAuthRepository(
          authRepoImpl: AuthRepoImpl
      ): AuthRepo<BeginSignInResult>
  }
  

• 或移除AuthRepoImpl的@Singleton，改用@ViewModelScoped：

  @ViewModelScoped
  class AuthRepoImpl @Inject constructor(
     ...
     @Named(SING_IN_RESULT)
     private val singInResult: BeginSignInResult,
     @Named(SING_UP_RESULT)
     private val singUpResult: BeginSignInResult,
     ...
  ) : AuthRepo<BeginSignInResult>
  

2. 修正挂起函数注入的逻辑问题 #

Hilt不支持直接注入suspend函数提供的实例（注入过程为同步），且BeginSignInResult是登录操作的动态结果，不适合作为构造参数注入（注入实例为一次性，无法满足每次登录获取新结果的需求）。

正确做法：将获取BeginSignInResult的逻辑移到仓库方法中，直接注入依赖的SignInClient和BeginSignInRequest：

@Singleton
class AuthRepoImpl @Inject constructor(
    private val oneTapClient: SignInClient,
    @Named(AuthConstant.SIGN_IN_REQUEST)
    private val signInRequest: BeginSignInRequest,
    @Named(AuthConstant.SIGN_UP_REQUEST)
    private val signUpRequest: BeginSignInRequest,
    ...
) : AuthRepo<BeginSignInResult> {
    override suspend fun oneTapSignInWithGoogle(): BeginSignInResult {
        return oneTapClient.beginSignIn(signInRequest).await()
    }

    // 同理实现其他登录方法
}

3. 检查命名常量拼写错误 #

代码中存在SING_IN_RESULT与SIGN_IN_REQUEST的拼写差异（SING vs SIGN），需确保所有@Named注解的常量字符串完全一致，避免Hilt无法匹配依赖。

内容的提问来源于stack exchange，提问作者chrrissoft