Q:

Using @Subcomponent android dagger 2.x not working

I'm facing an issue while trying to use Dagger's subcomponent. When I try to build this I get this error.

@Subcomponent.Builder setter methods must return void, the builder, or a supertype of the builder. Inherited method: create(T).

Does anyone have any idea what I'm doing wrong here?
Thanks.
@FragmentScope
@Subcomponent(modules = [OnBoardingWelcomeFragmentModule::class])
interface OnBoardingWelcomeFragmentComponent: AndroidInjector<OnBoardingWelcomeFragment> {

  @Subcomponent.Builder
  interface Builder: AndroidInjector.Factory<OnBoardingWelcomeFragment>

}

@Module
open class OnBoardingWelcomeFragmentModule {

  @Provides
  @FragmentScope
  fun provideUI() = OnBoardingWelcomeFragmentUi()

  @Provides
  @ViewModelForDagger
  fun providesViewModelForDagger(sharedPrefsStorage: SharedPrefsStorage): OnboardingViewModel =
    OnboardingViewModel(sharedPrefsStorage)

  @Provides
  fun providesViewModelFactory(@ViewModelForDagger
                               viewModel: Lazy<OnboardingViewModel>): ViewModelFactory<OnboardingViewModel> =
    ViewModelFactory(viewModel)

}

A:

You should switch AndroidInjector.Factory to AndroidInjector.Builder instead which implements AndroidInjector.Factory.
abstract class Builder: AndroidInjector.Builder<OnBoardingWelcomeFragment>

The Factory interface adds a method for dagger.android to use which you would have to implement yourself, since Dagger doesn't know how to—hence the error.

