Question

import UIKit
import Firebase
class LeaderBoardViewController: UIViewController {
    struct Person{
        var placePoints:Int
        var placeNames:String
    }
    var firstPlace = Person(placePoints:2,placeNames:"")
    var secondPlace = Person(placePoints:1,placeNames:"")
    var thirdPlace = Person(placePoints:1,placeNames:"")
    var check = 0
    var uid = ""
    var uniqueNumber:Int?
    var documentdata:[String:Any] = ["":""]
    @IBOutlet weak var firstPlaceLabel: UILabel!

    @IBOutlet weak var secondPlaceLabel: UILabel!

    @IBOutlet weak var thirdPlaceLabel: UILabel!

    @IBOutlet weak var reloadLabel: UILabel!
    override func viewDidLoad() {
        super.viewDidLoad()
        createLeaderboard()

        // Do any additional setup after loading the view.
    }

    func createLeaderboard(){
        let db = Firestore.firestore()
        db.collection("users").document("0UniqueNumber").getDocument { (document,error) in
            print("wheat the he")
            if error != nil{
                print("cant get data")

            }
            if document != nil && document!.exists{
                print("its here")
                if let documentdata = document?.data() {
                    self.uniqueNumber = documentdata["tally"] as? Int
                    print(self.uniqueNumber)
                    print("FDSFSF")
                    self.rat()
                }
            }
        }
    }
    func rat(){
        //var firstPlacePoints:Int?
        //var firstPlaceName:String?
        //var secondPlacePoints:Int?
        //var secondPlaceName:String?
        //var thirdPlacePoints:Int?
        //var thirdPlaceName:String?

        let db = Firestore.firestore()
        for index in 0...self.uniqueNumber!-1{
            let indexString = String(index)
            db.collection("leaderboard").document(indexString).getDocument { (document,error) in

                if error != nil{
                    print("cant get data")

                }
                if document != nil && document!.exists{

                    if let documentdata = document?.data() {
                        self.check = documentdata["points"] as! Int
                        self.uid = documentdata["uid"] as! String
                        print("ahwehfesfhsadfsfdsdfsdfsdfsdf")
                        if (self.check > self.firstPlace.placePoints){
                            self.secondPlace.placePoints = self.firstPlace.placePoints
                            self.secondPlace.placeNames = self.firstPlace.placeNames
                            self.firstPlace.placePoints = self.check
                            self.firstPlace.placeNames = self.uid

                            print("hi")
                        }else if(self.check < self.firstPlace.placePoints && self.secondPlace.placePoints < self.check){
                            self.thirdPlace.placePoints = self.secondPlace.placePoints
                            self.thirdPlace.placeNames = self.secondPlace.placeNames
                            self.secondPlace.placePoints = self.check
                            self.secondPlace.placeNames = self.uid

                        }else if(self.check < self.secondPlace.placePoints && self.thirdPlace.placePoints < self.check){
                            self.thirdPlace.placePoints = self.check
                            self.thirdPlace.placeNames = self.uid
                        }
                    }
                }
            }

            //setGuys()

        }
        print(self.firstPlace.placePoints)
    }
}

最后，当我打印self.firstPlace.placePoints时，它会在初始化时打印原始值。它会更改if语句中的值，然后使用print语句进行检查。但是就像我说的那样，当我运行print语句时，它不会更新。这是否与局部变量有关？谢谢您的帮助。

Answer 1

问题是您正在循环运行并正在调用异步方法。循环可能在异步方法完成之前完成。您应该等到异步方法完成后才能再次调用它。因此，可能会发生以下情况：

func createLeaderboard() {
    let db = Firestore.firestore()
    db.collection("users").document("0UniqueNumber").getDocument { document, error in
        guard let document = document,
            let documentData = document.data(),
            let tally = documentData["tally"] as? Int,
                document.exists,
                error == nil else {
                    print("Failed")
                    return
            }
        self.rat(index: 0, tally: tally)
    }
}

func rat(index: Int, tally: Int) {
    guard index < tally else {
        return
    }

    let indexString = String(index)
    let db = Firestore.firestore()
    db.collection("leaderboard").document(indexString).getDocument { document, error in
        guard let document = document,
            let documentData = document.data(),
            document.exists,
            error == nil else {
                print("Failed")
                return
        }

        guard let check = documentData["points"] as? Int,
            let uid = documentData["uid"] as? String else {
                print("Missing data")
                return
        }

        // ...
        // Do whatever else you have to do here
        // ...

        // Now you're ready make the next call
        self.rat(index: index + 1, tally: tally)
    }
}

即使在if状态菜单中运行，变量也不会更改

1 个答案: