我在服务中有2个单独的数据集合。
Featured
和Standard
内容。
我进行了2次api调用,以返回这些项目。它们可以单独使用,但是当我想同时使用两组数据,根据条件提供一些充实然后将它们返回给消费者时,我也有用例。
我希望我可以做这样的事情:
class ContentService: ContentServiceType {
let featured = PublishSubject<[Content]>()
let standard = PublishSubject<[Content]>()
let content: Observable<(featured: [Content], standard: [Content])>
private let client: Client<ContentAPI>
private let disposeBag = DisposeBag()
init(client: Client<ContentAPI>) {
self.client = client
content = Observable
.combineLatest(featured, standard)
.map { (featured, standard) -> (featured: [Content], standard: [Content]) in
/*
Do some enrichment and create then return new, updated versions
*/
return (featured: updatedFeatured, standard: updatedStandard)
}.share()
}
func fetchStandardContent(page: Int = 0, size: Int = 100) -> Single<Void> {
let params = ["page": page, "size": size]
let request: Single<Content> = client.request(.getStandardContent(params))
return request.map { [unowned self] launchers in
self.standard.onNext(content.props)
return ()
}
}
func fetchFeaturedContent(page: Int = 0, size: Int = 100) -> Single<Void> {
let params = ["page": page, "size": size]
let request: Single<Content> = client.request(.getFeaturedContent(params))
return request.map { [unowned self] content in
self.featured.onNext(content.props)
return ()
}
}
}
然后我希望在应用程序的其他地方可以做类似的事情
contentSvc.content
.observeOn(MainScheduler.instance)
.subscribeOn(ConcurrentDispatchQueueScheduler(qos: .background))
.subscribe(onNext: { content in
/* do something w/ content */
}).disposed(by: disposeBag)
然后每当调用contentSvc.fetchFeaturedContent
或contentSvc.fetchStandardContent
时,上方的contentSvc.content
用户将获得新数据。
相反,content
似乎没有发出任何值。
combineLatest
要求两个光源都必须先发射,然后才能发射自己。
我可能会考虑使用BehaviorSubject
或BehaviorRelay
代替PublishSubject。