swift - iosChart 不在 UITableViewCell 中显示 LineChartView 点

Question

以下基于 LineChartView 示例 ( from youtube )，它在标准 View (单 View 应用程序)中运行良好，而 BarChartView 在 TableViewCell 使用与下面所示相同的习惯用法。我有一个每两秒到期的时间来更新单元格，但尚未连接。

x,y 轴生成正确(最终图形仅显示 9 个单元格中的 2 个)，只是没有绘制点。但是，失败仅发生在 LineChartView 中。我查看了有关此问题的其他引用资料，但尚未找到我的具体修复方法。有什么想法吗？

TableViewController

class GraphTableTableViewController: UITableViewController {

    let model = [1,2,3,4,5,6,7,8,9]
    var timer: Timer? = nil
    var noSamples = 0

    override func viewDidLoad() {
        super.viewDidLoad()

        timer = Timer.scheduledTimer(timeInterval: 2.0, target: self, selector: #selector(fireTimer), userInfo: nil, repeats: true)
    }

    // MARK: - Table view data source

    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return model.count
    }


    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "lineChart_cell", for: indexPath)
        let graphCell = cell as? LineGraphCell

        graphCell!.setChartValues()
        print("\(model[indexPath.row])")
        return graphCell!
    }

    @objc func fireTimer() {
        print("Timer Fired")
        noSamples += 1
        (view as? UITableView)?.reloadData()
    }

}

TableViewCell 实现如下所示:

class LineGraphCell: UITableViewCell {

    @IBOutlet weak var lineChart: LineChartView!

    let x = [0,1,2,3,4,5,6,7,8,9]
    let y = [0,1,2,3,4,5,6,7,8,9]

    func setChartValues() {

        var values = [ChartDataEntry]()
        for index in x {
            let value = ChartDataEntry(x: Double(index), y: Double(y[index]))
            values.append(value)
        }

        let set1 = ChartDataSet(entries: values, label: "Set1")
        let data = ChartData(dataSet: set1)

        // Some debug output
        if data.entryCount > 0 {
            let yValue = "\(values[data.entryCount-1].y)"
            print("Y : \(yValue)")
            for value in values {
                print("\(value.y) ", terminator: "")
            }
        }
        self.lineChart.data = data
    }

}

Storyboard设置如下:

Answer 1

尝试使用以下...

let x = [0,1,2,3,4,5,6,7,8,9]
let y = [0,1,2,3,4,5,6,7,8,9]
func setChartValues() {

    var values = [ChartDataEntry]()
    for index in x {
        let value = ChartDataEntry(x: Double(index), y: Double(y[index]))
        values.append(value)
    }

let set1 = LineChartDataSet(entries: values, label: "Set1")
set1.color = UIColor.blue // red // green whatever you want. 
let data = LineChartData()
data.addDataSet(data:set1)

    // Some debug output
    if data.entryCount > 0 {
        let yValue = "\(values[data.entryCount-1].y)"
        print("Y : \(yValue)")
        for value in values {
            print("\(value.y) ", terminator: "")
        }
    }
    self.lineChart.data = data
}