swift - LineCharts 不显示来自 Realm 的数据

Question

我想向 LineCharts 显示我的数据。我检查了 Realm Studio，Realm 中保存了数据。它只是没有显示任何视图。也许我的代码出了点问题。

import UIKit
import Charts
import RealmSwift

class GraphViewController: UIViewController {

    @IBOutlet weak var linechart: LineChartView!
    weak var axisFormatDelegate: IAxisValueFormatter?

    override func viewDidLoad() {
        super.viewDidLoad()
        axisFormatDelegate = self
        // Do any additional setup after loading the view.
    
        //setLineGraph()
        updateChartWithData()
    }


    func updateChartWithData() {
        var dataEntries: [ChartDataEntry] = []
        let scoreCounts = getScoreFromDatabase()
        //let visitorCounts = getScoreFromDatabase()
        for i in 0..<scoreCounts.count {
            let timeIntervalForDate: TimeInterval =     scoreCounts[i].exactdate.timeIntervalSince1970
            let dataEntry = ChartDataEntry(x: Double(timeIntervalForDate), y: Double(scoreCounts[i].datesc))
        dataEntries.append(dataEntry)
        }
        let chartDataSet = LineChartDataSet(entries: dataEntries, label: "Score count" )
        linechart.data = LineChartData(dataSet: chartDataSet)
    
        linechart.chartDescription?.text = "Your Score"
    
        let xaxis = linechart.xAxis
        xaxis.valueFormatter = axisFormatDelegate
    }


    func getScoreFromDatabase() -> Results<DateScore> {
        let realm = try! Realm(configuration: Realm.Configuration(inMemoryIdentifier: "MyInMemoryRealm"))
        return realm.objects(DateScore.self)
      
        }

}
extension GraphViewController: IAxisValueFormatter {

  func stringForValue(_ value: Double, axis: AxisBase?) -> String {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "YYYY/MM/DD"
    return dateFormatter.string(from: Date(timeIntervalSince1970: value))
  }
}

这是我的领域类

import Foundation
import RealmSwift

class DateScore: Object {
    @objc dynamic var datesc : Int16 = 0
    @objc dynamic var exactdate : Date = Date()
}

我在下面收到错误消息这是相关的吗？

[未知进程名称] CGAffineTransformInvert：奇异矩阵。

我是初学者。谁能帮我？

标签： swiftxcodechartsrealmlinechart