Swift 3折线图获取索引

import UIKit
import Charts

class ViewController: UIViewController {

    @IBOutlet weak var lineChartView: LineChartView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建折线图数据
        let dataEntries = [
            ChartDataEntry(x: 0, y: 10),
            ChartDataEntry(x: 1, y: 20),
            ChartDataEntry(x: 2, y: 15),
            ChartDataEntry(x: 3, y: 25),
            ChartDataEntry(x: 4, y: 18)
        ]
        
        // 创建折线图数据集
        let chartDataSet = LineChartDataSet(entries: dataEntries, label: "折线图")
        
        // 创建折线图数据集数组
        let chartData = LineChartData(dataSet: chartDataSet)
        
        // 设置折线图视图属性
        lineChartView.data = chartData
        lineChartView.xAxis.labelPosition = .bottom
        
        // 获取折线图的索引
        let index = lineChartView.getHighlightByTouchPoint(CGPoint(x: 100, y: 100))?.x
        
        // 打印索引值
        if let index = index {
            print("折线图索引：\(index)")
        }
    }
}