具有ios-charts的特定欄上方文本的屬性

Question

如何更改BarChart中特定條形圖上方文本的屬性（例如字體大小，文本顏色等）？

在這個例子中，我想要紅色的“ - $ 5,000.00”並增加條形上方每個文本的字體大小。

這是一些代碼：

@IBOutlet weak var barChartView: BarChartView!


// init barChartView --------------------------------------
barChartView.descriptionText = ""

barChartView.legend.enabled = false

// grid lines
barChartView.xAxis.drawAxisLineEnabled = false
barChartView.xAxis.drawGridLinesEnabled = false
barChartView.leftAxis.drawAxisLineEnabled = false
barChartView.leftAxis.drawGridLinesEnabled = false
barChartView.rightAxis.drawAxisLineEnabled = false
barChartView.rightAxis.drawGridLinesEnabled = false

// X-axis line
barChartView.xAxis.drawAxisLineEnabled = true
barChartView.xAxis.axisLineColor = axisGridsAndLabelsColor

// X-axis labels
barChartView.xAxis.labelTextColor = axisGridsAndLabelsColor
barChartView.xAxis.labelPosition = .Bottom

// Y-axis labels
accountsBarChartView.leftAxis.labelTextColor = axisGridsAndLabelsColor
accountsBarChartView.rightAxis.drawLabelsEnabled = false
//---------------------------------------------------------


// bar chart's data
var dataPoints = [String]()
var values = [Double]()
var colors = [UIColor]()

// build bar chart's data...


// dataEntries and barChartDataSet
var dataEntries = [ChartDataEntry]()
for i in 0..<dataPoints.count
{
    let dataEntry = BarChartDataEntry(value: values[i], xIndex: i)
    dataEntries.append(dataEntry)
}

let barChartDataSet = BarChartDataSet(yVals: dataEntries, label: "")
barChartDataSet.colors = colors


// valueFormatter
let currencyNumberFormatter = NSNumberFormatter()
currencyNumberFormatter.numberStyle = .CurrencyStyle
currencyNumberFormatter.minimumFractionDigits = 2
currencyNumberFormatter.maximumFractionDigits = 2

barChartDataSet.valueFormatter = currencyNumberFormatter


// barChartData
let barChartData = BarChartData(xVals: dataPoints, dataSet: barChartDataSet)
barChartView.data = barChartData

Answer 1

要設置自己的顏色/字體，可以使用BarChartDataSet類的屬性valueColors和'valueFont'

所以它會是這樣的

...

var valueColors = [UIColor]()
// dataEntries and barChartDataSet
var dataEntries = [ChartDataEntry]()
for i in 0..<dataPoints.count
{
    let dataEntry = BarChartDataEntry(value: values[i], xIndex: i)
    dataEntries.append(dataEntry)
    if values[i] < 0 {
        valueColors.append(UIColor.redColor())
    }
    else {
        valueColors.append(UIColor.greenColor())
    }
}

let barChartDataSet = BarChartDataSet(yVals: dataEntries, label: "")
barChartDataSet.colors = colors
barChartDataSet.valueColors = valueColors
barChartDataSet.valueFont = *font you want*

Answer 2

如果要更改條形下方標簽的文本屬性，可以使用：

barChartView.xAxis.labelFont = UIFont.systemFont(ofSize: 5)

barChartView.xAxis.labelTextColor = UIColor.red