for循环，始终显示HTTP请求后的最后一个数组值swift 3 [英] for loop cycle showing always the last array value swift 3 after HTTP request

问题描述

我已经用另一篇文章来解决问题的一部分，所以现在我可以等待请求结束.我使用Almofire发出了http请求，并解析了生成的JSON文件.我认为myGroup.notify中的代码在请求完成后正确执行(如果我打印allCards.count返回正确的值).为什么如果我将for循环放入其中总是显示最后一张卡片呢?

I already used another post to solver part of the problem,so now I am able to wait the end of the request. I made a http request with Almofire and parse the resulting JSON file. the code inside the myGroup.notify i think is correctly executed ater the request is completed (if I print allCards.count returns the correct value). Why if I put the for loop inside it is always showing the last card?

感谢您的帮助

import UIKit
mport SwiftyJSON
import Alamofire

class ViewController: UIViewController {
//variables Declaration
var allCard = [Card]()
let allCardsHTTP: String = "https://omgvamp-hearthstone-v1.p.mashape.com/cards?mashape-key="

override func viewDidLoad() {
    super.viewDidLoad()
    let myGroup = DispatchGroup()

    //get HTTp request with Alamofire

    myGroup.enter()
    Alamofire.request(allCardsHTTP, method: .get).responseJSON {
         response in
         if response.result.isSuccess {
             let jsonCards : JSON = JSON(response.result.value!)
             print("success")
             self.updateJSONCards(json: jsonCards)
          }
        else {
             print("error")
         }
         myGroup.leave()
    }

    myGroup.notify(queue: .main) {
         //Updte UI here
         print(self.allCard[10].name) //This is Working

         for card in self.allCard {
            if card.cardsSet == "Basic" {
                print(card.name)
            }
        } //For loop always showing last card ???


    }
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


//MARK: - JSON Parsing


//Write the updateJSONCards method here:
func updateJSONCards(json: JSON) {
    //create the cards
     for (set, value) in json {
         var card = Card()
         card.cardsSet = set
         if json[set].count != 0 {
            for i in 0...json[set].count - 1 {
                card.name = json[set][i]["name"].stringValue
                allCard.append(card)
             }
         }
         else {
             print("The set \(set) has no cards")
         }
     }
  }

}

推荐答案

您在错误的位置创建了Card实例.

You are creating the Card instance at the wrong place.

在内部重复循环之前，您将创建一个实例并将相同实例附加到allCard数组.如果Card是类(引用语义)，则该实例的所有出现都包含相同的数据(最后一个循环项).

Before the inner repeat loop you are creating one instance and appending the same instance to the allCard array. If Card is a class (reference semantics) all occurrences of that instance contain the same data (the last loop item).

将两行放入重复循环中.

//Write the updateJSONCards method here:
func updateJSONCards(json: JSON) {
    //create the cards
     for (set, value) in json {
         if !json[set].isEmpty {
            for i in 0..<json[set].count {
                let card = Card()
                card.cardsSet = set
                card.name = json[set][i]["name"].stringValue
                allCard.append(card)
             }
         }
         else {
             print("The set \(set) has no cards")
         }
     }
  }

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