创建可观察对象数组后在RxSwift中使用zip运算符

时间:2018-08-16 05:17:32

标签: ios swift rx-swift rx-cocoa

我有一个newBid对象,其中包含一些数据和图像数组。我想将所有图像和数据上传到服务器,并zip上载可观察的图像。如果我为driversdataimage1创建单独的image2,则成功。

但是我真正想做的是不对图像进行硬编码,因为数组可能包含0到10张图像。我想以编程方式创建可观察对象数组,并zip

let dataSaved = saveTaps.withLatestFrom(newBid)
    .flatMapLatest { bid in
        return CustomerManager.shared.bidCreate(bid: bid)
            .trackActivity(activityIndicator)
            .asDriver(onErrorJustReturn: false)
}

let photoSaved0 = saveTaps.withLatestFrom(newBid)
    .flatMapLatest { bid in
        return CustomerManager.shared.bidUploadFile(image: bid.images[0])
            .trackActivity(activityIndicator)
            .asDriver(onErrorJustReturn: false)
}

let photoSaved1 = saveTaps.withLatestFrom(newBid)
    .flatMapLatest { bid in
        return CustomerManager.shared.bidUploadFile(image: bid.images[1])
            .trackActivity(activityIndicator)
            .asDriver(onErrorJustReturn: false)
}

saveCompleted = Driver.zip(dataSaved, photoSaved0, photoSaved1){ return $0 && $1 && $2 }

/*
// 0. Getting array of images from newBid
let images = newBid.map { bid in
    return bid.images
}

// 1. Creating array of upload drivers from array of images
let imageUploads = images.map { (images: [UIImage]) -> [Driver<Bool>] in
    var temp = [Driver<Bool>]()
    return temp
}

// 2. Zipping array of upload drivers to photoSaved driver
photoSaved = Driver
    .zip(imageUploads) // wait for all image requests to finish
    .subscribe(onNext: { results in
        // here you have every single image in the 'images' array
        results.forEach { print($0) }
    })
    .disposed(by: disposeBag)*/

在带注释的部分中,如果我尝试进行zip imageUploads,则会收到错误消息:

Argument type 'SharedSequence<DriverSharingStrategy, [SharedSequence<DriverSharingStrategy, Bool>]>' does not conform to expected type 'Collection'

2 个答案:

答案 0 :(得分:1)

这样的事情怎么样?

let saves = saveTaps.withLatestFrom(newBid)
    .flatMapLatest { (bid: Bid) -> Observable<[Bool]> in
        let dataSaved = CustomerManager.shared.bidCreate(bid: bid)
            .catchErrorJustReturn(false)

        let photosSaved = bid.images.map {
            CustomerManager.shared.bidUploadFile(image: $0, bidID: bid.id)
                .catchErrorJustReturn(false)
        }

        return Observable.zip([dataSaved] + photosSaved)
            .trackActivity(activityIndicator)
    }
    .asDriver(onErrorJustReturn: []) // remove this line if you want an Observable<[Bool]>.

答案 1 :(得分:0)

最终解决方案

let bidID: Driver<Int> = saveTaps.withLatestFrom(newBid)
    .flatMapLatest { bid in
        return CustomerManager.shared.bidCreate(bid: bid)
            .trackActivity(activityIndicator)
            .asDriver(onErrorJustReturn: 0)
}

saveCompleted = Driver.combineLatest(bidID, newBid) { bidID, newBid in
    newBid.uploadedImages.map {
        CustomerManager.shared.bidUploadFile(image: $0, bidID: bidID).asDriver(onErrorJustReturn: false)
    }
    }.flatMap { imageUploads in
        return Driver.zip(imageUploads).trackActivity(activityIndicator).asDriver(onErrorJustReturn: [])
    }.map{ (results:[Bool]) -> Bool in
        return !results.contains(false)
}

这是等效的组合版本:

let imageUploads: Driver<[Driver<Bool>]> = Driver.combineLatest(bidID, newBid) { bidID, newBid in
    newBid.uploadedImages.map {
        CustomerManager.shared.bidUploadFile(image: $0, bidID: bidID).asDriver(onErrorJustReturn: false)
    }
}

let photosSaved: Driver<[Bool]> = imageUploads.flatMap { imageUploads in
    return Driver.zip(imageUploads).trackActivity(activityIndicator).asDriver(onErrorJustReturn: [])
}

saveCompleted = photosSaved.map{ (results:[Bool]) -> Bool in
    return !results.contains(false)
}