iOS Charts - single values not showing Swift

Question

When I have multiple points in an array for a line on a line graph, everything shows perfectly. But when there is only one point, the dot does not show. I dont know why? the delegate is being set elsewhere, but this doesnt seem to be the issue.

The below examples shows Test 2 and Test exercise. The first image is where each has one value, the second they each have 2.

heres my code

    func startChart(){

        chart.dragEnabled = true
        chart.legend.form = .circle
        chart.drawGridBackgroundEnabled = false

        let xaxis = chart.xAxis

        xaxis.valueFormatter = axisFormatDelegate
        xaxis.labelCount = dataSets.count
        xaxis.labelPosition = .bottom

        xaxis.granularityEnabled = true
        xaxis.granularity = 1.0
        xaxis.avoidFirstLastClippingEnabled = true
        xaxis.forceLabelsEnabled = true
        let rightAxis = chart.rightAxis

        rightAxis.enabled = false
        rightAxis.axisMinimum = 0

        let leftAxis = chart.leftAxis
        leftAxis.drawGridLinesEnabled = true
        leftAxis.axisMinimum = 0

        let chartData = LineChartData(dataSets: dataSets)
        chart.data = chartData
 }

If I add

chart.setVisibleXRangeMinimum(myMinDate)

the value will show correctly. however it squashes the value to the left and overlaps 2 x value dates

Answer 1

The only way I could get around this was to add an additional invisible line.

I created a clear line that started the day before and ended the day after my single values.

As long as there is a line on the chart that goes from one point to another, the other single values show.

  var singleValue = false
    for i in 0...(dataSets.count - 1) {
        if dataSets[i].values.count > 1{
            singleValue = true
        }
    }
    var data = dataSets
    if singleValue == false {
        let minNS = Calendar.current.date(byAdding: .day, value: -1, to: minNSDate as! Date)
        let maxNS =  Calendar.current.date(byAdding: .day, value: 1, to: maxNSDate as! Date)

        var dataEntries: [ChartDataEntry] = []

        let dataEntry1 = ChartDataEntry(x:Double(String(format: "%.2f",Double((minNS?.timeIntervalSince1970)!)))!,y:00.00)
        let dataEntry2 = ChartDataEntry(x:Double(String(format: "%.2f",Double((maxNS?.timeIntervalSince1970)!)))!,y:00.00)
        dataEntries.append(dataEntry1)
        dataEntries.append(dataEntry2)
        let set = LineChartDataSet(values: dataEntries, label: "")
        set.setCircleColor(UIColor.clear)
        set.circleHoleColor = UIColor.clear
        set.setColor(UIColor.white, alpha: 0.0)
        set.drawValuesEnabled = false
        data.append(set)

    }
    chart.chartDescription?.text = ""
    let chartData = LineChartData(dataSets: data)
    chart.data = chartData