IAxisValueFormatter Error: Index out of range

[chetanpanchal94]

What did you do?

I have created one IAxisValueFormatter which returns xAxis label value as string.
Chart is being displayed and xAxis labels are also being displayed using the formatter which i have created. Once chart is displayed, when I am zooming in the line chart and stack bar chart till all xAxsis labels are visible and change device orientation from portrait to landscape app crashes and gives me error index out of range

My XAxisValueFormatter

// Stores xAxis labels

var xAxisLabels = [String]()

public class XAxisValueFormatter: NSObject, IAxisValueFormatter {

    private let dateFormatter = DateFormatter()

    public func stringForValue(_ value: Double, axis: AxisBase?) -> String {
    
    return xAxisLabels[Int(value)] // error

    }
}

What did you expect to happen?

After zooming in line and stack bar chart till all its xAxis labels are visible and change device orientation from portrait to landscape chart should be displayed in landscape mode.

What happened instead?

App is crashing and gives me error on the below line
" return xAxisLabels[Int(value)] "

Solution

Need help or suggest me other IAxisValueFormatter which can be used to display xAxis label value as string

[chetanpanchal94]

Easy fix

var xAxisLabels = [String]()

public class XAxisValueFormatter: NSObject, IAxisValueFormatter 
{
     private let dateFormatter = DateFormatter()
     public func stringForValue(_ value: Double, axis: AxisBase?) -> String 
     {
        if(Int(value) >= xAxisLabels.count) 
        {
           return ""
        }
      return xAxisLabels[Int(value)]
   }
 }

[denys-meloshyn]

Did you have any chance to find why it is happening?