Change data if button press

[sheldy995]

In UIView I have buttons( 1,2,3,4) and UIView with Charts

I want if button1 press - remove old data line and show new with new data^ and if press button2 similar reload

func populateData(withCount countA: [Double], countB: [Double]) {
     for index in 0..<countB.count{
               let dataEntry = ChartDataEntry(x: countB[index], y: countA[index])
               values.append(dataEntry)
           }
    let set = LineChartDataSet(values: values, label: "")
           set.mode = .cubicBezier
           set.cubicIntensity = 0.2
           set.drawCirclesEnabled = true
           set.lineWidth = 2.7
           set.circleRadius = 2.8
           set.setCircleColor(.green)
           set.setColor(#colorLiteral(red: 0.3176470588, green: 0.9960784314, blue: 0.6549019608, alpha: 1))
           set.fillColor = .green
           set.fillAlpha = 1.0
           set.drawHorizontalHighlightIndicatorEnabled = false
           set.drawVerticalHighlightIndicatorEnabled = false
            let gradientColors = [UIColor.cyan.cgColor, UIColor.clear.cgColor] as CFArray 
           let colorLocations:[CGFloat] = [1.0, 0.0] 
           let gradient = CGGradient.init(colorsSpace: CGColorSpaceCreateDeviceRGB(), colors: gradientColors, locations: colorLocations
           set.fill = Fill.fillWithLinearGradient(gradient!, angle: 90.0) 
           set.drawFilledEnabled = true 
           
           
           let data = LineChartData(dataSet: set)
           data.setDrawValues(false)
           chartView.data = data
       }

In viewDidLoad I load data from button1:

let a: [Double] = [2.530, 2.014, 2.625, 1.898, 0.556, 2.3767, 2.554, 2.6676, 1.8777, 2.098, 2.567, 3.0, 3.5, 3.7, 3.2]
      let b: [Double] = [1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0]
      
      let c: [Double] = [1.530, 3.014, 0.625, 3.898, 2.556, 3.3767, 1.554, 1.6676, 3.8777, 1.098, 3.567, 2.0, 2.5, 1.7, 2.2]
      let d: [Double] = [1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0, 13.0, 14.0, 15.0]
  
          override func viewDidLoad() {
          super.viewDidLoad()
          populateData(withCount: a, countB: b)
          }

In button1:

chartView.clear()
    populateData(withCount: a, countB: b)

In button2:

 chartView.clear()
     populateData(withCount: c, countB: d)

But it's not work, data does't change, only add and show 2 lines

How can I delete and put new data?

[sheldy995]

Create

func populateData(withCount countA: [Double], countB: [Double]) {
  values = []
  for index in 0..<countB.count{
      let dataEntry = ChartDataEntry(x: countB[index], y: countA[index])
      values.append(dataEntry)
        }

[liuxuan30]

ask on stack overflow please.