can not draw circle on axis as the picture

[zhpt]

can not draw circle on axis as the picture, please help me solve it. Thanks a lot.

This is my code

chartView1.chartDescription?.enabled = false
chartView1.dragEnabled = true
chartView1.setScaleEnabled(false)
// chartView1.setScaleMinima(3, scaleY: 0)
chartView1.pinchZoomEnabled = false
chartView1.dragDecelerationEnabled = true //拖拽后是否有惯性效果
chartView1.dragDecelerationFrictionCoef = 0.1 //拖拽后惯性效果的摩擦系数(0~1)，数值越小，惯性越不明显
chartView1.delegate = self // built in delegate for user interaction
chartView1.legend.enabled = false

    let xAxis = chartView1.xAxis
    xAxis.labelFont = .systemFont(ofSize: 11)
    xAxis.labelTextColor = .white
    xAxis.axisMaximum = 30
    xAxis.axisMinimum = 0
    xAxis.labelPosition = .bottom
    xAxis.axisLineColor = .white //轴颜色
    xAxis.axisLineWidth = 1 //x轴宽度
    // 设置坐标间隔
    xAxis.labelCount = 30
    xAxis.granularityEnabled = true
    xAxis.granularity = 1
    xAxis.gridColor = UIColor(red: 0.85, green: 0.85, blue: 0.85, alpha: 0.1) //x轴对应网格线的颜色
   
    
    let leftAxis = chartView1.leftAxis
    leftAxis.labelFont = .systemFont(ofSize: 11)
    leftAxis.labelTextColor = .white
    leftAxis.axisMaximum = 260
    leftAxis.axisMinimum = 0
    leftAxis.zeroLineColor = .white
    leftAxis.zeroLineWidth = 2
    // 设置坐标间隔
    leftAxis.labelCount = 13
    leftAxis.granularityEnabled = true
    leftAxis.granularity = 1
    leftAxis.gridColor = UIColor(red: 0.85, green: 0.85, blue: 0.85, alpha: 0.1) //轴对应网格线的颜色
    leftAxis.axisLineColor = .white //轴颜色
    leftAxis.axisLineWidth = 2 //x轴宽度
    leftAxis.drawTopYLabelEntryEnabled = false
    leftAxis.drawBottomYLabelEntryEnabled = false
    
    //        let targetLine = ChartLimitLine(limit: 250, label: "")
    //        leftAxis.addLimitLine(targetLine)
    //        targetLine.lineColor = .white
    
    chartView1.rightAxis.enabled = false

let set1 = LineChartDataSet(values: dataEntry, label: "DataSet")
set1.axisDependency = .left
set1.setColor(items[index].color) // 折线本身的颜色
set1.setCircleColor(items[index].color) // 拐点颜色
set1.lineWidth = 2
set1.drawCirclesEnabled = true // 是否绘制拐点

        if self.canEdit {
            set1.circleRadius = 6 // 圆的半径
            set1.drawCircleHoleEnabled = true //是否画空心圆
            set1.circleHoleRadius = 4// 空心圆的半径
            set1.circleHoleColor = .white // 空心圆的颜色
        }else {
             set1.circleRadius = 3
            set1.drawCircleHoleEnabled = false
        }
        set1.highlightColor = UIColor(red: 0.84, green: 0.6, blue: 0.38, alpha: 1) //十字线颜色
        set1.highlightLineWidth = 2 //十字线线宽
        set1.highlightLineDashLengths = [4, 2] //使用虚线样式的十字线
        set1.drawVerticalHighlightIndicatorEnabled = true
        set1.drawHorizontalHighlightIndicatorEnabled = true
        set1.highlightEnabled = canEdit

[liuxuan30]

fixed