func chartValueSelected(_ chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight) {
    let translation1 = CGAffineTransform(scaleX: 1.5, y: 1.5)
    let translation2 = CGAffineTransform(translationX: 1.0, y: 1.0)
    UIView.animate(withDuration: 0.4, animations: { in
        entry.transform = translation1
    }) { didComplete in
        UIView.animate(withDuration: 0.4, animations: {
            entry.transform = translation2
        })
    }
}

self.pieChart.highlightPerTapEnabled = true