let data = CSPieChartData(key: "test", value: 70)

public protocol CSPieChartDataSource {

    ///  Component data
    func numberOfComponentData() -> Int
    func pieChart(_ pieChart: CSPieChart, dataForComponentAt index: Int) -> CSPieChartData

    ///  Component colors
    func numberOfComponentColors() -> Int
    func pieChart(_ pieChart: CSPieChart, colorForComponentAt index: Int) -> UIColor

    ///  If you are implement this, you can show subView. example) 'UIImageView' or 'UILable'
    @objc optional func numberOfComponentSubViews() -> Int
    @objc optional func pieChart(_ pieChart: CSPieChart, viewForComponentAt index: Int) -> UIView

    ///  If you are implement this, you apply color to line path
    ///  Otherwish line color is applied default 'black'
    @objc optional func numberOfLineColors() -> Int
    @objc optional func pieChart(_ pieChart: CSPieChart, lineColorForComponentAt index: Int) -> UIColor
}

public protocol CSPieChartDelegate {

    /// Component select
    @objc optional func pieChart(_ pieChart: CSPieChart, didSelectComponentAt index: Int)
}

    //  Pie chart radius rate that is percentage of frames in the superview. default is 0.7
    public var pieChartRadiusRate: CGFloat = 0.7
    
    // Pie chart line length between component and subview. default is 10
    public var pieChartLineLength: CGFloat = 10
    
    //  This is piechart component selecting animation. default is none
    public var seletingAnimationType: SelectingAnimationType = .none
}

  func ViewDidLoad(...) {
      ....
      pieChart.show(animated: true)
  }