danielgindi/iOSCharts chartValueSelected not called - ios

Question

I am using danielgindi/iOSCharts library to crate combined line&bar charts like below.
My chart is rendered correctly and it has user interactions like tap and pinch zoom. Also chart is able to detect my tap gesture. But somehow
func chartValueSelected(chartView: ChartViewBase, entry: ChartDataEntry, dataSetIndex: Int, highlight: Highlight){
print("###################")
}
cannot be called. Really need some help here.
What I want to implement is that both balloon mark with same X value would show if I click on either a bar or a point on line. (both mark in above two pictures will display at same time when I tap a bar or a point)
Below is my entire controller code:
class FirstViewController: UIViewController,ChartViewDelegate {
#objc(ChartFormatter)
public class ChartFormatter: NSObject, IAxisValueFormatter{
var months: [String]! = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
public func stringForValue(_ value: Double, axis: AxisBase?) -> String {
return months[Int(value)]
}
}
#IBOutlet weak var chartView: CombinedChartView!
var lineChartData = LineChartData()
var barChartData = BarChartData()
override func viewDidLoad() {
super.viewDidLoad()
chartView.delegate = self
chartView.chartDescription?.enabled = true
chartView.dragEnabled = true
chartView.setScaleEnabled(true)
chartView.pinchZoomEnabled = true
chartView.drawGridBackgroundEnabled = false
let xAxis:XAxis = chartView.xAxis
xAxis.labelPosition = .bottom
xAxis.labelFont = UIFont.systemFont(ofSize: 11.0)
xAxis.labelTextColor = UIColor.black
xAxis.drawGridLinesEnabled = true
xAxis.drawAxisLineEnabled = false
xAxis.drawLabelsEnabled = false
let leftAxis:YAxis = chartView.leftAxis;
leftAxis.labelTextColor = UIColor(red: 1, green: 165/255, blue: 0, alpha: 1)
leftAxis.axisMaximum = 5.0
leftAxis.axisMinimum = -5.0
leftAxis.drawGridLinesEnabled = false
leftAxis.drawZeroLineEnabled = true
leftAxis.granularityEnabled = true
leftAxis.drawLabelsEnabled = false
let rightAxis:YAxis = chartView.rightAxis
rightAxis.enabled = false
let credit: [Double] = [1.0, 4.0, 2.0, 3.0, 3.0, 1.0, 3.0, 0.0, 0.0, 0.0, 0.0]
let gpa: [Double] = [-1.0, -4.0, -1.5, -1.4, -1.3, -1.0, -3.0, 0.0, 0.0, 0.0, 0.0]
let chartDescription = ""
let marker = BalloonMarker(color: UIColor(white: 180/255, alpha: 1.0), font: UIFont.systemFont(ofSize:12.0), textColor: UIColor.white, insets: UIEdgeInsetsMake(8.0, 8.0, 20.0, 8.0))
marker.chartView = chartView
marker.minimumSize = CGSize(width:80.0, height:40.0)
chartView.marker = marker
self.setLineChart(dataPoints: gpa, chartDescription: chartDescription)
self.setBarChart(dataPoints: credit)
self.setChartData()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func setLineChart(dataPoints: [Double], chartDescription: String) {
let formatter:ChartFormatter = ChartFormatter()
let xaxis:XAxis = XAxis()
var dataEntries: [ChartDataEntry] = Array()
for i in 0..<dataPoints.count {
let dataEntry = ChartDataEntry(x: Double(i), y: dataPoints[i])
dataEntries.append(dataEntry)
formatter.stringForValue(Double(i), axis: xaxis)
}
let lineChartDataSet = LineChartDataSet(values: dataEntries, label: "Credit")
self.lineChartData = LineChartData(dataSet: lineChartDataSet)
xaxis.valueFormatter = formatter
chartView.xAxis.valueFormatter = xaxis.valueFormatter
xaxis.drawGridLinesEnabled = false
lineChartDataSet.mode = .linear
lineChartDataSet.drawCirclesEnabled = false
lineChartDataSet.drawValuesEnabled = false
lineChartDataSet.colors = [UIColor.brown]
chartView.descriptionText = chartDescription
}
func setBarChart(dataPoints: [Double]) {
let formatter:ChartFormatter = ChartFormatter()
let xaxis:XAxis = XAxis()
var dataEntries: [BarChartDataEntry] = Array()
for i in 0..<dataPoints.count {
let dataEntry = BarChartDataEntry(x: Double(i), y: dataPoints[i])
dataEntries.append(dataEntry)
formatter.stringForValue(Double(i), axis: xaxis)
}
let barChartDataSet = BarChartDataSet(values: dataEntries, label: "GPA")
self.barChartData = BarChartData(dataSet: barChartDataSet)
xaxis.valueFormatter = formatter
chartView.xAxis.valueFormatter = xaxis.valueFormatter
xaxis.drawGridLinesEnabled = false
barChartDataSet.drawValuesEnabled = false
}
func setChartData() {
let data:CombinedChartData = CombinedChartData()
data.lineData = self.lineChartData
data.barData = self.barChartData
chartView.data = data
chartView.data?.highlightEnabled = true
//chartView.autoScaleMinMaxEnabled = true
//chartView.setNeedsDisplay()
}
#objc func chartValueSelected(chartView: ChartViewBase, entry: ChartDataEntry, dataSetIndex: Int, highlight: Highlight){
print("###################")
}
#objc func chartValueNothingSelected(chartView: ChartViewBase){
NSLog("chartValueNothingSelected");
}
}

Answer 1

Chiming in very late here, but the method signature has changed in Swift 3.0 (see this answer), and no longer includes dataSetIndex.
You should be able to see this firing in the console by changing your function signature (and implementation) to the following:
func chartValueSelected(chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight){
print("###################")
}

Answer 2

Now it's
func chartValueSelected(_ chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight){
print("Point: \(entry.x) Value: \(entry.y)")
}