IOS Swift, Пользовательский рендер для значений гистограммы в гистограмме

Question

Я использую библиотеку диаграмм (https://github.com/danielgindi/Charts, Спасибо Даниэлю) для рисования различных диаграмм в приложениях Android и IOS.Мне нужны сгруппированные гистограммы и значения баров высоки.Поэтому, когда я отображаю, значения перекрываются.Я использовал пользовательский рендерер для своего приложения Android, и он будет показывать значения по вертикали, как на скриншоте.Теперь мне нужно то же самое для приложения IOS.

Вот мой быстрый код для ios:

func setBarChart(barchart: BarChartView, chartData: BarData){

        let groupSpace = 0.16
        let barSpace = 0.03
        let barWidth = 0.25

        let yearlyData = [YearlyData] (chartData.data!)

        var months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]


        let tempData1 = [ReportData] (yearlyData[0].data!)
        let tempData2 = [ReportData] (yearlyData[1].data!)
        let tempData3 = [ReportData] (yearlyData[2].data!)

        var yearlyData1 = [Double]()
        var yearlyData2 = [Double]()
        var yearlyData3 = [Double]()

        for i in 0..<12 {
            yearlyData1.append(Double(tempData1[i].value!)!)
            yearlyData2.append(Double(tempData2[i].value!)!)
            yearlyData3.append(Double(tempData3[i].value!)!)
        }

        barchart.noDataText = "no_data_found".localized
        barchart.noDataTextColor = textColour
        barchart.chartDescription?.text = ""
        barchart.drawValueAboveBarEnabled = true
        barchart.legend.enabled = true

        barchart.xAxis.drawGridLinesEnabled = false
        barchart.xAxis.labelTextColor = textColour
        barchart.xAxis.labelPosition = .bottom
        barchart.xAxis.labelCount = months.count
        barchart.xAxis.labelRotationAngle = 0.0
        barchart.xAxis.valueFormatter = IndexAxisValueFormatter(values:months)
        barchart.xAxis.granularityEnabled = true
        barchart.xAxis.granularity = 1
        barchart.xAxis.axisMinimum = 0
        barchart.xAxis.centerAxisLabelsEnabled = true
        barchart.xAxis.axisMaximum = 12
        barchart.xAxis.labelPosition = .top
        barchart.rightAxis.enabled = false
        barchart.leftAxis.labelTextColor = textColour
        barchart.leftAxis.drawGridLinesEnabled = false
        barchart.leftAxis.axisMinimum = 0

        barchart.fitBars = true

        var dataEntries1: [BarChartDataEntry] = []
        var dataEntries2: [BarChartDataEntry] = []
        var dataEntries3: [BarChartDataEntry] = []
        var counter = 0.0

        for i in 0..<months.count {
            let dataEntry1 = BarChartDataEntry(x: counter, y: yearlyData1[i])
            dataEntries1.append(dataEntry1)
            let dataEntry2 = BarChartDataEntry(x: counter, y: yearlyData2[i])
            dataEntries2.append(dataEntry2)
            let dataEntry3 = BarChartDataEntry(x: counter, y: yearlyData3[i])
            dataEntries3.append(dataEntry3)
            counter += 1.0
        }

        let chartDataSet1 = BarChartDataSet(values: dataEntries1, label: "2017")
        chartDataSet1.colors = [UIColor.red]
        chartDataSet1.valueColors = [textColour]

        let chartDataSet2 = BarChartDataSet(values: dataEntries2, label: "2018")
        chartDataSet2.colors = [UIColor.orange]
        chartDataSet2.valueColors = [textColour]

        let chartDataSet3 = BarChartDataSet(values: dataEntries3, label: "2019")
        chartDataSet3.colors = [UIColor.green]
        chartDataSet3.valueColors = [textColour]

        let chartData = BarChartData()
        chartData.addDataSet(chartDataSet1)
        chartData.addDataSet(chartDataSet2)
        chartData.addDataSet(chartDataSet3)
        chartData.barWidth = barWidth
        barchart.data = chartData

        barchart.setVisibleXRangeMaximum(4.0)

        barchart.groupBars(fromX: 0, groupSpace: groupSpace, barSpace: barSpace)
        barchart.animate(yAxisDuration: 0.5, easingOption: .easeInExpo)
    }