我正在使用图表框架（由 Daniel gindi 设计）。工作正常但是 如何在饼图上显示%（符号）？
我还尝试使用 NSNumberFormatter() 方法将数据值转换为百分比，但没有得到 % 符号。
我在这里上传代码

    @IBOutlet var pieChart: PieChartView!
    override func viewDidLoad() {
            super.viewDidLoad()
            var data = [25.0,37.5,12.5,12.5,12.5] // pie chart data 
            var status = ["A","B","C","D","E"] // status
            setChart(status, values: data)
            self.pieChart.drawSliceTextEnabled = false

    }
    func setChart(dataPoints: [String], values: [Double]) {

            pieChart.noDataText = "you need to provide data for chart"
            pieChart.noDataTextDescription = ""
            self.pieChart.descriptionText = ""

            var dataEntries: [ChartDataEntry] = []
            //pieChart.centerText = " "
            for i in 0..<dataPoints.count {

                let dataEntry = ChartDataEntry(value: values[i], xIndex: i)
                dataEntries.append(dataEntry)

            }

            let pieChartDataSet = PieChartDataSet(yVals: dataEntries, label: "")

            var colors: [UIColor] = []


            for _ in 0..<dataPoints.count {
                let red = Double(arc4random_uniform(256))
                let green = Double(arc4random_uniform(256))
                let blue = Double(arc4random_uniform(256))

                let color = UIColor(red: CGFloat(red/255), green: CGFloat(green/255), blue: CGFloat(blue/255), alpha: 1)
                colors.append(color)

                pieChartDataSet.colors = colors

            }

            let pieChartData = PieChartData(xVals: dataPoints, dataSet: pieChartDataSet)

            pieChart.data = pieChartData
            pieChart.animate(yAxisDuration: 2.0, easingOption: .EaseInOutBack)
}

输出：=>

On Swift3与最新版本的charts https://github.com/danielgindi/Charts你可以做%饼图的格式如下：

    let formatter = NumberFormatter()
    formatter.numberStyle = .percent
    formatter.maximumFractionDigits = 1
    formatter.multiplier = 1.0
    pieChartData.setValueFormatter(DefaultValueFormatter(formatter:formatter))