相关组件中的Dagger2和限定符 [英] Dagger2 and qualifiers in dependent components

问题描述

我有一个应用程序组件和一个从属组件.应用程序组件声明显式依赖项，并且依赖项组件可以注入这些依赖项.但是，当我有一个必须与@Qualifier消除歧义的依赖项时，该依赖项组件将无法注入该依赖项.

I have an app component and a dependent component. The app component declares explicit dependencies, and the dependent component can inject those. However, when I have a dependency that I have to disambiguate with a @Qualifier, the dependent component is not able to inject that dependency.

这是应用程序组件

@Component(modules = [AppModule::class, SchedulersModule::class, StorageModule::class])

@ApplicationScope
interface AppComponent {
    fun inject(app: Application)
    /* other stuff omitted for brevity */
    val bitmapCache: BitmapCache        
    @UiScheduler fun uiScheduler(): Scheduler
}

这是调度程序模块:

@Module
class SchedulersModule {
    @ApplicationScope
    @Provides
    @IoScheduler
    fun provideIoScheduler(): Scheduler = Schedulers.io()

    @ApplicationScope
    @Provides
    @UiScheduler
    fun provideMainThreadScheduler(): Scheduler = AndroidSchedulers.mainThread()
}

这是预选赛:

@Qualifier
@Retention(AnnotationRetention.RUNTIME)
annotation class UiScheduler

这是从属组件:

@Component(
        dependencies = [AppComponent::class],
        modules = [EditEntryActivityModule::class, ViewModelModule::class]
)

@ActivityScope
interface EditEntryActivityComponent {
    fun inject(editEntryActivity: EditEntryActivity)
    fun inject(editEntryFragment: EditEntryFragment)
}

这是将调度程序注入片段的方式:

This is how the scheduler is injected in the fragment:

class EditEntryFragment : Fragment() {
    @Inject @UiScheduler lateinit var uiScheduler: Scheduler
    /* other stuff */
}

那么为什么从属组件可以注入在父组件中声明的位图缓存，而不是UI调度程序?这是我得到的错误:

So why can the dependent component inject the bitmap cache, declared in the parent component, but not the UI scheduler? This is the error I get:

error: io.reactivex.Scheduler cannot be provided without an @Provides- or @Produces-annotated method.
  io.reactivex.Scheduler is injected at
      com.test.edit.EditEntryFragment.uiScheduler
  com.test.edit.EditEntryFragment is injected at
      com.test.edit.EditEntryActivityComponent.inject(arg0)
1 error

推荐答案

在类EditEntryFragment中使用@field:UiScheduler

Using @field:UiScheduler in class EditEntryFragment

这篇关于相关组件中的Dagger2和限定符的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！