ios - Swift - 无法调用类型 'NSDictionary' 的初始值设定项

Question

自升级到 Xcode7 后，出现以下错误:

Cannot invoke initializer for type 'NSDictionary' with an argument list of type '(objects: [AnyObject!], forKeys: [String])'

在这行代码中:

self.sessionBids!.addObject(NSDictionary(objects: [PFUser.currentUser().objectId, PFUser.currentUser().objectForKey("username"), self.bidTextField.text], forKeys: ["user", "name", "bid"]))

谁能解释一下为什么？

编辑:这是完整的代码块

if(self.bidTextField.text!.rangeOfString("^[0-9]*$", options: .RegularExpressionSearch) != nil) {
                    self.sessionBids = array[0].objectForKey("bids") as? NSMutableArray
                    var lastSessionBid : NSDictionary
                    SVProgressHUD.showProgress(50)
                    var previousHighBid : Int! = 0
                    if(self.sessionBids == nil) {
                        self.sessionBids = NSMutableArray()

                    } else {
                        lastSessionBid = self.sessionBids.objectAtIndex(self.sessionBids.count - 1) as! NSDictionary
                        previousHighBid = Int(lastSessionBid.objectForKey("bid") as! String)
                    }

                    if( previousHighBid >= Int(self.bidTextField.text!)) {
                        print("bid is lower than current bid")
                        SVProgressHUD.showErrorWithStatus("Bid is lower than current bid!")
                        return

                    } else {

                        self.sessionBids!.addObject(NSDictionary(objects: [PFUser.currentUser().objectId, PFUser.currentUser().objectForKey("username"), self.bidTextField.text], forKeys: ["user", "name", "bid"]))
                        SVProgressHUD.showProgress(75)
                        self.session.setObject(self.sessionBids, forKey: "bids")
                        self.session.save()
                        self.keyboardShowing = false
                        self.reloadSessionBids()
                        SVProgressHUD.showProgress(100)
                        SVProgressHUD.showSuccessWithStatus("Successfully Added Bid")
                    }

                } else {
                    SVProgressHUD.showErrorWithStatus("Bid must be a number!")
                }

Answer 1

您正在尝试调用 NSDictionary 的 init(objects: [AnyObject], forKeys keys: [NSCopying]) 初始化程序。 objects: [AnyObject] 不能包含 Optionals(根据它的声明)，似乎 PFUser.currentUser().objectId, PFUser.currentUser( ).objectForKey("username"), self.bidTextField.text 都是可选的，这就是你得到错误的原因。

要解决这个问题，如 vadian建议，您需要解包该数组中的所有 Optionals。