import UIKit
import Charts
 
class ViewController: UIViewController {
     
    //折线图
    var chartView: LineChartView!
     
    override func viewDidLoad() {
        super.viewDidLoad()
         
        //创建折线图组件对象
        chartView = LineChartView()
        chartView.frame = CGRect(x: 20, y: 80, width: self.view.bounds.width - 40,
                                 height: 250)
        self.view.addSubview(chartView)
         
        //设置交互样式
        chartView.scaleXEnabled = false //允取消X轴缩放
        chartView.scaleYEnabled = false //取消Y轴缩放
        chartView.doubleTapToZoomEnabled = false //双击缩放
         
         
        //生成100条随机数据
        var dataEntries = [ChartDataEntry]()
        for i in 0..<100 {
            let y = arc4random()%100
            let entry = ChartDataEntry.init(x: Double(i), y: Double(y))
            dataEntries.append(entry)
        }
        //这50条数据作为1根折线里的所有数据
        let chartDataSet = LineChartDataSet(values: dataEntries, label: "客流量（天）")
        //目前折线图只包括1根折线
        let chartData = LineChartData(dataSets: [chartDataSet])
         
        //设置折线图数据
        chartView.data = chartData
         
        //图表最多显示10个点
       chartView.setVisibleXRangeMaximum(10)
        //默认显示最一个数据
       chartView.moveViewToX(99)
    }
}

import UIKit
import Charts
 
class ViewController: UIViewController, ChartViewDelegate {
     
    //折线图
    var chartView: LineChartView!
     
    override func viewDidLoad() {
        super.viewDidLoad()
         
        //创建折线图组件对象
        chartView = LineChartView()
        chartView.frame = CGRect(x: 20, y: 80, width: self.view.bounds.width - 40,
                                 height: 250)
        chartView.delegate = self //设置代理
        self.view.addSubview(chartView)
         
        //设置交互样式
        chartView.scaleXEnabled = false //允取消X轴缩放
        chartView.scaleYEnabled = false //取消Y轴缩放
        chartView.doubleTapToZoomEnabled = false //双击缩放
         
        //生成100条随机数据
        var dataEntries = [ChartDataEntry]()
        for i in 0..<100 {
            let y = arc4random()%100
            let entry = ChartDataEntry.init(x: Double(i), y: Double(y))
            dataEntries.append(entry)
        }
        //这50条数据作为1根折线里的所有数据
        let chartDataSet = LineChartDataSet(values: dataEntries, label: "客流量（天）")
        //目前折线图只包括1根折线
        let chartData = LineChartData(dataSets: [chartDataSet])
         
        //设置折线图数据
        chartView.data = chartData
         
        //图表最多显示10个点
        chartView.setVisibleXRangeMaximum(10)
        //默认显示最一个数据
        chartView.moveViewToX(99)
    }
     
    //折线上的点选中回调
    func chartValueSelected(_ chartView: ChartViewBase, entry: ChartDataEntry,
                            highlight: Highlight) {
        //将该点居中（其实就是将该点左边第5个点移动道图表左侧）
        self.chartView.moveViewToAnimated(xValue: entry.x - 5, yValue: 0,
                                          axis: .left, duration: 1)
    }
}