@IBOutlet weak var iosSlidder: UISlider!

@IBOutlet weak var macSlidder: UISlider!

@IBOutlet weak var pieChart: PieChartView!

var iosDataEntry = PieChartDataEntry(value: 0)
var macDataEntry = PieChartDataEntry(value: 0)

var numberOfDownloadsDataEntries = [PieChartDataEntry]()

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.
    pieChart.chartDescription?.text = ""

    iosDataEntry.value = Double(iosSlidder.value)
    iosDataEntry.label = "iOS"

    macDataEntry.value = Double(macSlidder.value)
    macDataEntry.label = "iOS"

    numberOfDownloadsDataEntries = [iosDataEntry, macDataEntry]
    updateChartData()
}
@IBAction func changeiOS(_ sender: UISlider)
{
    iosDataEntry.value = Double(sender.value)
    updateChartData()

}
@IBAction func changeMac(_ sender: UISlider)
{
    macDataEntry.value = Double(sender.value)
    updateChartData()
}

func updateChartData()
{
    let chartDataSet =  PieChartDataSet(entries: numberOfDownloadsDataEntries , label:nil)
    let charData = PieChartData(dataSet: chartDataSet)
    let colors = [UIColor(named: "iosColor"), UIColor(named: "macColor")]
    chartDataSet.colors = colors as! [NSUIColor]
    pieChart.data = charData
}