Question

我想映射一个字典和flatMap一起返回一个新的Observable。我正在尝试Observable，因为我可能是一个单个对象或一个对象数组。

func fetchRibsList() -> Observable<[LCLRibAccount]>  {
        return provider.rxDict(service: .fetchRibsList)
            .map({ (dict, _) -> [String: Any] in
                return dict
            })
            .filter({ dict -> Bool in
                dict["ribs"] != nil
            })
            .filter({ dict -> Bool in
                dict["rib"] != nil
            })
            .flatMap({ dict -> Observable<Any> in

                //return either list of ribs or 1 single rib
                if let ribs = dict["ribs"] as? [String: Any] {
                    return Observable.just(LCLRib.parseAccountList(with: ribs))
                }

                if let rib = dict["rib"] as? [String: Any] {
                    return Observable.just(LCLRib.parseRib(with: rib))
                }

                return Observable.empty()
            })
    }

是否可以包含带有2个flatMap的条件并返回一个数组或一个单个对象问题是我需要具体使用Observable类型：

这是我得到的错误：无法转换类型＆＃39; Observable＆＃39;的返回表达式返回类型＆＃39; Observable＆lt; [LCLRibAccount]＆gt;＆＃39;

Answer 1

问题是你的函数的返回类型func fetchRibsList() -> Observable<[LCLRibAccount]>。它期望一个数组的Observable。也许你可以将单个对象包装在一个数组中。像这样：

func fetchRibsList() -> Observable<[LCLRibAccount]>  {
    return provider.rxDict(service: .fetchRibsList)
        .map({ (dict, _) -> [String: Any] in
            return dict
        })
        .filter({ dict -> Bool in
            dict["ribs"] != nil
        })
        .filter({ dict -> Bool in
            dict["rib"] != nil
        })
        .flatMap({ dict -> Observable<[LCLRibAccount]> in

            //return either list of ribs or 1 single rib
            if let ribs = dict["ribs"] as? [String: Any] {
                return Observable.just(LCLRib.parseAccountList(with: ribs))
            }

            if let rib = dict["rib"] as? [String: Any] {
                return Observable.just([LCLRib.parseRib(with: rib)]) //wrap single object in array
            }

            return Observable.empty()
        })
}

使用rx Swift过滤条件

1 个答案: