无法展开Promise<[CLPlacemark]> ]

Question

我有一种方法试图更新我的授权状态。

使用PromiseKit 6，SWIFT4.2，我似乎不能让我的Promise成为一个CLPlacemark。

这将导致一系列错误。

Value of type 'Promise<[CLPlacemark]>' has no member 'foo'

下面看看我的代码：

func updateAuthStatus(status: CLAuthorizationStatus) {
    if status == .authorizedWhenInUse {
        titleLabel.isHidden = true
        bigIconView.isHidden = true
        descriptionLabel.isHidden = true
        grantBtn.isHidden = true
        titleLabel1.isHidden = false
        loaderView.isHidden = false
        loaderView.resumeSpinning()
        CLLocationManager.requestLocation().compactMapValues { location in
            return self.coder.reverseGeocode(location: location)
        }.compactMapValues { placemark -> Void in
            if placemark.ISOcountryCode == "CA" {
                self.seal.fulfill(())
            } else if placemark.ISOcountryCode == "US" {
                if self.allowedStates.contains(placemark.administrativeArea ?? "") {
                    self.seal.fulfill(())
                } else {
                        self.seal.reject(LocationError.InvalidState(placemark.administrativeArea ?? ""))
                }
            } else {
        self.seal.reject(LocationError.InvalidCountry(placemark.ISOcountryCode ?? ""))
            }
        }
    }
    else if status == .denied || status == .restricted {
        if denied == false {
            self.seal.reject(LocationError.Unknown)
        }
        denied = true
    }
}

Answer 1

正如您所提到的，这个promise正在返回一个CLPlacemark对象数组，因此您需要从array中获取特定的placemark，然后使用它。下面是通过访问first placemark在array中的示例。

.compactMapValues { placemarks -> Void in
            guard let placemark = placemarks.first else { return }

            if placemark.ISOcountryCode == "CA" {
                self.seal.fulfill(())
            } else if placemark.ISOcountryCode == "US" {
                if self.allowedStates.contains(placemark.administrativeArea ?? "") {
                    self.seal.fulfill(())
                } else {
                  self.seal.reject(LocationError.InvalidState(placemark.administrativeArea ?? ""))
                }
            } else {
        self.seal.reject(LocationError.InvalidCountry(placemark.ISOcountryCode ?? ""))
            }
        }

编辑

要处理美国和CA，可以提取该国的相关地名如下，

.compactMapValues { placemarks -> Void in
       if let ca = placemarks.filter{ $0.ISOcountryCode == "CA"}.first {
            self.seal.fulfill(())
       } else if let usa = placemarks.filter{ $0.ISOcountryCode == "US"}.first {
            if self.allowedStates.contains(usa.administrativeArea ?? "") {
                self.seal.fulfill(())
            } else {
                let error = LocationError.InvalidState(usa.administrativeArea ?? "")
                self.seal.reject(error)
            }
    } else {
         let error = LocationError.InvalidCountry(placemarks.first?.ISOcountryCode ?? "")
         self.seal.reject(error)
     }
 }