ios - 升级到 Xcode 8 和 Swift 3.0 后使用 Google Places iOS SDK 出现无法解释的异常

Question

在将其转换为 swift 3.0 后，我什至无法使用演示代码。我已经尝试了我能想到的一切都无济于事。

异常非常无用，堆栈跟踪也是如此。 (见截图)

这是 swift 2.3 代码，运行良好:

@IBAction func getCurrentPlace(sender: UIButton) {

    placesClient?.currentPlaceWithCallback({
    (placeLikelihoodList: GMSPlaceLikelihoodList?, error: NSError?) -> Void in
        if let error = error {
            print("Pick Place error: \(error.localizedDescription)")
            return
        }

        self.nameLabel.text = "No current place"
        self.addressLabel.text = ""

        if let placeLikelihoodList = placeLikelihoodList {
            let place = placeLikelihoodList.likelihoods.first?.place
            if let place = place {
                self.nameLabel.text = place.name
                self.addressLabel.text = place.formattedAddress!.componentsSeparatedByString(", ")
                    .joinWithSeparator("\n")
            }
        }
    })
}

这在 swift 3.0 中是等价的:

@IBAction func go(_ sender: AnyObject) {
    var placesClient: GMSPlacesClient?
    placesClient = GMSPlacesClient.shared()
    placesClient?.currentPlace(callback: {
        (placeLikelihoodList: GMSPlaceLikelihoodList?, error: NSError?) in

        if let error = error {
            print("Pick Place error: \(error.localizedDescription)")
            let alert = UIAlertController(title: "Error", message: "Couldn't find a location", preferredStyle: UIAlertControllerStyle.alert)
            alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil))
            self.present(alert, animated: true, completion: nil)

            return
        }

        if let placeLikelihoodList = placeLikelihoodList {
            let place = placeLikelihoodList.likelihoods.first?.place
            if let place = place {
                self.testlabel.text = place.name
            }
        }


        } as! GMSPlaceLikelihoodListCallback)
}

异常阻止了我:as! GMSPlaceLikelihoodListCallback

有人知道发生了什么事吗？

Answer 1

    var placesClient: GMSPlacesClient?
    placesClient = GMSPlacesClient.shared()
    placesClient?.currentPlace(callback: { (place, error) in
        if let error = error {
            print("Pick Place error: \(error.localizedDescription)")
            let alert = UIAlertController(title: "Error", message: "Couldn't find a location", preferredStyle: UIAlertControllerStyle.alert)
            alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil))
            self.present(alert, animated: true, completion: nil)

            return
        }

        if let placeLikelihoodList = place {
            let place = placeLikelihoodList.likelihoods.first?.place
            if let place = place {
                self.lblOrigem.text = place.formattedAddress
            }
        }
    })