iOS 图表显示从 API 检索数据之前 - swift

Question

我正在尝试使用 iOS 图表创建我的第一个实时图表并从数据库中提取数据。

我的数据库中的数据包括获胜、平局、失败的比赛。这些是整数(但是 iOS 图表要求它们是 double ，但这是另一个问题)。

我的主要问题是图表没有随我的数据更新 - 如果我在行中手动输入数据，即 let games = [4.0, 8.0, 2.0]，它就可以工作。但是从数据库中提取数据后我什么也没得到。

import UIKit
import Charts

class ShowCommunityViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {

//********CHART VARIABLES**************//

var totalWins: Double = 0.0
var totalDraws: Double = 0.0
var totalLosses: Double = 0.0

//**************************************

override func viewDidLoad() {

    results =  ["Won", "Drawn", "Lost"]
    let games = [totalWins, totalDraws, totalLosses]
    setChart(dataPoints: results, values: games)

}

// ******* CHARTS FUNCTIONS ************

func setChart(dataPoints: [String], values: [Double]){

    barChartView.noDataText = "you need to provide some data for the chart."

    var dataEntries: [BarChartDataEntry] = Array()

    for i in 0..<dataPoints.count {
        let dataEntry = BarChartDataEntry(x: Double(i), y: values[i])
        dataEntries.append(dataEntry)
    }

    let chartDataSet = BarChartDataSet(values: dataEntries, label: "Games Played")

    let chartData = BarChartData()
    self.barChartView.xAxis.labelPosition = XAxis.LabelPosition.bottom
    barChartView.leftAxis.granularityEnabled = true
    barChartView.rightAxis.enabled = false
    barChartView.leftAxis.granularity = 1.0
    chartData.addDataSet(chartDataSet)
    barChartView.data = chartData

}

// ********* API CALL *****

 override func viewDidAppear(_ animated: Bool) {

    let defaults = UserDefaults.standard
    let playerId = defaults.string(forKey: "playerId")
    let email = defaults.string(forKey: "userEmail")

    self.personalSelf = true

    let myUrl = URL(string: "http://www.xxx.uk/xxx/xxx.php?");
    var request = URLRequest(url:myUrl!);
    request.httpMethod = "POST";

    let postString = "community_id=\(comIds[communityId!])&player_id=\(playerId!)&email=\(email!)";

    request.httpBody = postString.data(using: String.Encoding.utf8);

    let task = URLSession.shared.dataTask(with: request) { (data: Data?, response: URLResponse?, error: Error?) in

        DispatchQueue.main.async
            {

                if error != nil {
                    print("error=\(error)")
                    return
                }

                do{
                    let json = try JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? [String:AnyObject]
                    print (json!)

                if let dict = json?["Stats"] as? [String:AnyObject] {
                    if  let total_Wins = dict["totalWins"] as? Double,
                        let total_Draws = dict["totalDraws"] as? Double,
                        let total_Losses = dict ["totalLosses"] as? Double{
                    self.totalWins = total_Wins
                    self.totalDraws = total_Draws
                    self.totalLosses = total_Losses
                    }


                } catch{
                    print(error)
                }
        }
        }
    task.resume()


}

我的问题是图表没有更新。我猜这是因为图表是在获取数据之前显示的？

...顺便说一句，我更愿意显示 Int 而不是 Floats 但它要求所有内容都是 double

我哪里出错了？

更新:

解决方案有效 - 显示 float 而不是整数，并且图表底部缺少标签，显示数字而不是“赢”、“画”、“输”

Answer 1

self.totalWins = total_Wins
 self.totalDraws = total_Draws
 self.totalLosses = total_Losses

//在您的响应中添加此行

results =  ["Won", "Drawn", "Lost"]
let games = [total_Wins, total_Draws, total_Losses]
setChart(dataPoints: results, values: games)

检查输出。