Charts是一个强大的图表框架，MPAndroidChart 在 iOS 上的移植。可以绘制线形图，直方图，饼状图等等。(由于在项目中只做了饼状图，这里就只有饼状图的代码了，其它的图基本上用法类似)

更新：适配3.0版本

首先需要import Charts

绘制饼状图：

var viewPie: PieChartView!

创建饼状图:

func initChart () {
        // 基本样式
        viewPie?.setExtraOffsets(left: 0, top: 0, right: 0, bottom: 0) //饼状图距离边缘的间隙
        viewPie?.usePercentValuesEnabled = false //是否根据所提供的数据, 将显示数据转换为百分比格式
        viewPie?.dragDecelerationEnabled = false //拖拽饼状图后是否有惯性效果
        viewPie?.drawSliceTextEnabled = false //是否显示区块文本
        // 空心圆样式
        viewPie?.drawHoleEnabled = true //饼状图是否是空心
        viewPie?.rotationEnabled = false // 旋转指示
        viewPie?.descriptionText = "" // 文本内容
        viewPie?.holeRadiusPercent = 0.5 //空心半径占比
        viewPie.holeColor = UIColor.clearColor() //中心颜色
        viewPie?.transparentCircleRadiusPercent = 0.6 //半透明空心半径占比
        viewPie.drawCenterTextEnabled = true //中心的文本启用
    }

没有数据时饼状图的状态:

func setChartDataEmpty() {
        var yValues:[BarChartDataEntry] = []
        let entryValue = BarChartDataEntry.init(x: 0, yValues: [Double(1)])
        yValues.append(entryValue)
        
        let dataSet = PieChartDataSet.init(yVals: yValues, label: "")
        dataSet.drawValuesEnabled = false
        dataSet.selectionShift = 0
        dataSet.valueLineVariableLength = false
        
        var colors: [UIColor] = []
        colors.append(UIColor.init(hexValue: "c0c0c0"))
        
        dataSet.colors = colors
        
        let data = PieChartData.init(xVals: xValues, dataSet:dataSet)
        viewPie?.data = data
}

数据为空的圆饼图

填充数据:

// 动画效果
func doAnimate() -> Void {
        viewPie?.animate(xAxisDuration: 1, easingOption: ChartEasingOption.EaseOutSine)
    }
    
func setChartData() {
        doAnimate()
        //此处填入展示的相应数字
        let value1 = Double(1)
        let value2= Double(1)
    
        if value1 + value2 == 0 {
            setChartDataEmpty()
            return
        }
        let xValues:[String] = []
        
        var yValues:[ChartDataEntry] = []
        let entryValue1 = BarChartDataEntry.init(x: 1, yValues: [value1])
        let entryValue2 = BarChartDataEntry.init(x: 2, yValues: [value2] )
        
        yValues.append(entryValue1)
        yValues.append(entryValue2)
        
        let dataSet = PieChartDataSet.init(yVals: yValues, label: "")
        dataSet.drawValuesEnabled = false
        dataSet.selectionShift = 0
        dataSet.valueLineVariableLength = false
        
        var colors: [UIColor] = []
        colors.append(UIColor.init(hexValue: "eb9837"))
        colors.append(UIColor.init(hexValue: "90c549"))
        
        dataSet.colors = colors
        
        let data = PieChartData.init(xVals: xValues, dataSet: dataSet)
        
        viewPie?.data = data
    }

填充数据后的饼状图