ios - RxSwift - 使用两个可观察对象进行异步调用

Question

假设我有一个接受两个参数的函数 - Observable<String?>和 Observable<Person? > 并返回 Observable

下面是我的示例代码:

return  Observable.combineLatest(self.id, personStream)
                  map { [weak self] (id,person) -> Person? in

     guard let person = person as? Person else {
       return nil
     }

    if let id = id {
       // How do I return this updated person
       self?.updatePersonDetails(for: person, completion: { (updatedPerson) in
            return updatedPerson
       })     
    } else {
       return person
    }
}

我如何在这个映射函数中返回这个更新的人？

更新:

public func updatePerson(personStream: Observable<Person>) -> Observable<Person> {
    return Observable.combineLatest(
            self.id,
            personStream
        ).flatMap { [weak self] (id,person) -> Observable<Person?> in

            guard let person = person as? Double else {
                return Observable.just(nil)
            }

            if let id = id {
                // How do I return this updated person
                return Observable.create { [weak self] observer in
                    self?.updatePersonDetails(for: person, completion: { (updatedPerson) in
                        observer.on(.next(updatedPerson))
                        observer.on(.completed)
                    })
                    return Disposables.create()
                }
            } else {
                return Observable.just(person)
            }
        }
}

上面的函数调用如下:

let personUpdateStream = personService.updatePerson(personStream: personDataStream)
Observable.combineLatest(personUpdateStream, nameStream,profileEnabledStream)
.subscribe(onNext: { [weak self] (person, name, isEnabled) in
                print(name)
                self?.updatePersonView(person: person, name: name, isLocked: !isEnabled)
            })
            .disposed(by: disposeBag)

问题:combineLatest 中的 block 与 print(name)从不运行。我可以知道这里有什么问题吗？

personUpdateStream 的描述

personUpdateStream RxSwift.FlatMap<(String?, Person?), RxSwift.Observable<Person?>> 0x0000604001e5af70

Answer 1

您应该使用 flatMap 而不是 map 并且要集成您的 updatePersonDetails 的非 Rx 调用，您应该使用 Observable.create.

您的最终代码应类似于:

return Observable.combineLatest(
            self.id,
            personStream
        ).flatMap { [weak self] (id,person) -> Observable<Person?> in

            guard let person = person as? Double else {
                return Observable.just(nil)
            }

            if let id = id {
                // How do I return this updated person
                return Observable.create { [weak self] observer in
                    self?.updatePersonDetails(for: person, completion: { (updatedPerson) in
                        observer.on(.next(updatedPerson))
                        observer.on(.completed)
                    })
                    return Disposables.create()
                }
            } else {
                return Observable.just(person)
            }
        }