danielgindi/Charts Pie Chart selected index

Question

I am using Charts to draw a pie chart. It is working fine but i need to pass the selected portion index to next viewcontroller. I used below code and also read their release notes for Charts 3.0. I am working in Swift 3. In previous version the selected index was got from entry.dataSetIndex.

By this code i always get 0 index. Any help please.

extension ViewController: ChartViewDelegate {

    func chartValueSelected(_ chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight) {

        print(highlight.dataSetIndex)
    }

}

Answer 1

Using iOS Charts 3.0.0, the following code outputs the selected index:

class ChartController: UIViewController, ChartViewDelegate {

func chartValueSelected(_ chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight) {

    if let dataSet = chartView.data?.dataSets[ highlight.dataSetIndex] {

        let sliceIndex: Int = dataSet.entryIndex( entry: entry)
        print( "Selected slice index: \( sliceIndex)")
    }
}

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear( animated)

    // 1. create chart view
    let chart = PieChartView( frame: self.view.frame)
    chart.delegate = self

    // TODO: exercise for reader...add data, styles, etc.
}