IOS图表仅在中间突出显示X轴上的特定标签和虚线虚线

时间:2019-02-20 02:44:54

标签: ios swift ios-charts

我试图根据当月的当前日期为X轴上的标签设置不同的颜色,但是我似乎无法单独配置它们。我还尝试使网格线的中线带有破折号,而天花板线则不带破折号。这在左轴上。但是我似乎也不能单独设置它。

目前如何:

enter image description here

我想要实现的目标:

enter image description here

到目前为止,我的代码:

func setBarChart(dataPoints: [String], values: [String]){
    barChartView.noDataTextColor = UIColor.white
    barChartView.noDataText = "No data for the chart"
    barChartView.backgroundColor = UIColor.white

    for i in 0..<dataPoints.count {
        let dataPoint = BarChartDataEntry(x: Double(i), y: Double(values[i])!)
        dataEntry.append(dataPoint)
    }

    let chartDataSet = BarChartDataSet(values: dataEntry, label: "BPM")
    let chartData =  BarChartData()
    chartData.addDataSet(chartDataSet)
    chartData.setDrawValues(false)
    chartData.barWidth = Double(0.5)
    chartDataSet.colors = [UIColor(red: 0, green: 158/255, blue: 237/255, alpha: 1)]


    let formatter: ChartFormatter = ChartFormatter ()
    formatter.setValues(values: dataPoints)
    let floatValue: [CGFloat] = [4,4]
    barChartView.xAxis.valueFormatter = formatter
    barChartView.xAxis.labelTextColor = UIColor(red: 141/255, green: 141/255, blue: 141/255, alpha: 1)
    barChartView.getAxis(.right).labelTextColor = UIColor(red: 141/255, green: 141/255, blue: 141/255, alpha: 1)
    barChartView.xAxis.axisLineColor = UIColor.clear
    barChartView.getAxis(.right).axisLineColor = UIColor.clear
    barChartView.getAxis(.left).axisLineColor = UIColor.clear
    barChartView.xAxis.labelPosition = .bottom
    barChartView.xAxis.drawGridLinesEnabled = false
    barChartView.xAxis.drawLabelsEnabled = true
    barChartView.chartDescription?.enabled = false
    barChartView.legend.enabled = false
    barChartView.rightAxis.enabled = true
    barChartView.rightAxis.labelCount = Int(2)
    barChartView.rightAxis.drawGridLinesEnabled = false
    barChartView.leftAxis.drawGridLinesEnabled = true
    barChartView.leftAxis.gridColor = UIColor(red: 235/255, green: 235/255, blue: 235/255, alpha: 1)
    barChartView.leftAxis.gridLineWidth = CGFloat(1.5)
    barChartView.leftAxis.gridLineDashLengths = floatValue
    barChartView.leftAxis.drawLabelsEnabled = false
    barChartView.data = chartData
}

1 个答案:

答案 0 :(得分:1)

该功能在库中不可用。


但是,这不应该阻止您自己实现它,甚至不能将其添加到库中。

首先,请查看具有drawLabels(context:pos:anchor:)的{​​{3}}。

这里,它基本上遍历xAxis.entries并通过调用drawLabel(context:formattedLabel:x:y:attributes:constrainedToSize:anchor:angleRadians:)并为其传递一个labelAttrs来绘制每个标签,该标签具有有关要应用的颜色的信息。
但是目前... labelAttrs设置为循环之前的一种颜色,该颜色引用自xAxis.labelTextColor

此处的关键是将labelAttrs[NSAttributedString.Key.foregroundColor]设置为相对于条目的颜色,例如,在此行附近:

let label = xAxis.valueFormatter?.stringForValue(xAxis.entries[i], axis: xAxis) ?? ""

如果颜色也要由xAxis.valueFormatter提供,那可能是最好的,而这反过来又需要更改IAxisValueFormatter才能提供。

希望这对您有所帮助。