Android Hilt ViewModel 无法检测依赖项

Question

申请

@HiltAndroidApp
class MyApplication : Application()

模块

@Module
@InstallIn(ActivityComponent::class, FragmentComponent::class)
class ApplicationModule {
    @Provides
    fun provideService(): Service = ServiceImpl()
}

片段

@AndroidEntryPoint
class MyFragment: Fragment() {
    @Inject lateinit var service: Service
}

到目前为止一切正常，现在我尝试创建一个 ViewModel 并将服务移入 viewModel

视图模型

@HiltViewModel
class WinnersViewModel @Inject constructor(
    private val service: Service
) : ViewModel()

更新片段

@AndroidEntryPoint
class MyFragment: Fragment() {
    private val viewModel: WinnersViewModel by viewModels()
}

此时我开始出现编译错误

/Users/user/Desktop/Repos/App/Android/app/build/generated/source/kapt/debug/com/app/Application_HiltComponents.java:124: error: [Dagger/MissingBinding] com.comp.app.services.Service cannot be provided without an @Provides-annotated method.
  public abstract static class SingletonC implements Application_GeneratedInjector,
                         ^
      com.comp.app.services.Service is injected at
          com.comp.app.winners.WinnersViewModel(service)
      com.comp.app.winners.WinnersViewModel is injected at
          com.comp.app.winners.WinnersViewModel_HiltModules.BindsModule.binds(vm)
      @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.comp.app.Application_HiltComponents.SingletonC → com.comp.app.Application_HiltComponents.ActivityRetainedC → com.comp.app.Application_HiltComponents.ViewModelC]

知道问题出在哪里吗？

Answer 1

您必须在模块中选择 SingletonComponent，如下所示：

@Module
@InstallIn(SingletonComponent::class)
class ApplicationModule {

    @Provides
    fun provideService(): Service = ServiceImpl()
}

Android Hilt ViewModel 无法检测依赖项

Android Hilt ViewModel can't detect dependency

android

dagger

android-viewmodel

dagger-hilt