Question

我使用Dagger 2作为DI工具，我有多个数据源：

本地数据库远程服务器我有以下用例：

GetNewspaperUseCase 现在我希望能够从本地数据库和远程服务器获取报纸。

我有两个资格：

DatabaseQualifer
NetworkQualifer

这是Database qualifer：

@Qualifier
@Documented
@Retention(RUNTIME)
public @interface DatabaseQualifer {
 }

这是网络资格：

@Qualifier
@Documented
@Retention(RUNTIME)
public @interface NetworkQualifer {
}

我有模块：

@Module
public class NewspaperModule {

private GetNewspaperView getNewspaperView;
private DownloadNewspaperView downloadNewspaperView;
private SaveNewspaperView saveNewspaperView;

public NewspaperModule(GetNewspaperView getNewspaperView, DownloadNewspaperView downloadNewspaperView, SaveNewspaperView saveNewspaperView) {
    this.getNewspaperView = getNewspaperView;
    this.downloadNewspaperView = downloadNewspaperView;
    this.saveNewspaperView = saveNewspaperView;
}

@Provides
@FragmentScoped
@NetworkQualifer
NewspaperDataSource providesDataSource(Retrofit retrofit){
    return new NewspaperNetworkDataSource(retrofit);
}

@Provides
@FragmentScoped
@DatabaseQualifer
NewspaperDataSource providesDatabaseDataSource(AppDatabase appDatabase){
    return new NewspaperDatabaseDataSource(appDatabase);
}


@Provides
@FragmentScoped
NewspaperRepository provideRepository(NewspaperDataSource dataSource){
    return new NewspaperRepositoryImpl(dataSource);
}

@Provides
@FragmentScoped
@NetworkQualifer
GetNewspapersInteractor provideGetNewspaperInteractor(NewspaperRepository repository){
    return new GetNewspapersInteractorImpl(repository);
}

@Provides
@FragmentScoped
@DatabaseQualifer
GetNewspapersInteractor provideGetNewspaperFromDatabase(NewspaperRepository repository){
    return new GetNewspapersFromDatabaseInteractor(repository);
}

@Provides
@FragmentScoped
@NetworkQualifer
GetNewspaperPresenter provideGetNewspaperPresenter(GetNewspapersInteractor interactor){
    return new GetNewspaperPresenterImpl(interactor, getNewspaperView);
}

@Provides
@FragmentScoped
@DatabaseQualifer
GetNewspaperPresenter provideGetNewspaperFromDatabasePresenter(GetNewspapersInteractor interactor){
    return new GetNewspapersFromDatabasePresenter(interactor, getNewspaperView);
}

@Provides
@FragmentScoped
DownloadNewspaperInteractor provideDownloadNewspaperInteractor(NewspaperRepository repository){
    return new DownloadNewspaperInteractorImpl(repository);
}

@Provides
@FragmentScoped
DownloadNewspaperPresenter provideDownloadNewspaperPresenter(DownloadNewspaperInteractor interactor){
    return new DownloadNewspaperPresenterImpl(interactor, downloadNewspaperView);
}

@Provides
@FragmentScoped
SaveNewspaperInteractor provideSaveNewspaperInteractor(NewspaperRepository repository){
    return new SaveNewspaperInteractorImpl(repository);
}

@Provides
@FragmentScoped
SaveNewspaperPresenter provideSaveNewspaperPresenter(SaveNewspaperInteractor interactor){
    return new SaveNewspaperPresenterImpl(interactor, saveNewspaperView);
}

}

以下是Component：

中的代码

@FragmentScoped
@Component(dependencies = DataComponent.class, modules =    NewspaperModule.class)
public interface NewspaperComponent {
void inject(NewspaperFragment fragment);
}

现在我有片段，我正在尝试使用@NetworkQualifer @Inject，但是我收到了错误。

以下是Fragment的代码：

@Inject @NetworkQualifer GetNewspaperPresenter getNewspapersPresenter;

这是错误：

错误：（14,10）错误：如果没有@ Provide-annotated方法，则无法提供at.volksoper.volksoperrefactored.domain.newspapers.get.GetNewspapersInteractor。 at.volksoper.volksoperrefactored.domain.newspapers.get.GetNewspapersInteractor注入 at.volksoper.volksoperrefactored.presentation.newspapers.NewspaperModule.provideGetNewspaperPresenter（交互器） @ at.volksoper.volksoperrefactored.presentation.newspapers.NetworkQualifer at.volksoper.volksoperrefactored.presentation.newspapers.get.GetNewspaperPresenter注入 at.volksoper.volksoperrefactored.presentation.newspapers.NewspaperFragment.getNewspapersPresenter at.volksoper.volksoperrefactored.presentation.newspapers.NewspaperFragment注入 at.volksoper.volksoperrefactored.presentation.newspapers.NewspaperComponent.inject（片段）

如何使用@Qualifers与Dagger 2相同类型的多个实例？

0 个答案: