How to set a custom x axis 0 label in charts ios

Question

I am using Charts by Daniel Gindi

How can I set a String 0 label on x Axis? I want it to show "Now" instead of a Date type. I've seen the function that helps to format one particular label only, but I can't get how it works. Moreover, I haven't seen any examples of it. So, how does getFormattedLabel(index: Int) work? This is what I need my xAxis to look like:

Thank you!

Answer 1

This is a snippet that helps me convert an X axis into timeline and also make the last label on the chart of a String type.

index == count - 2 was used because the label count on X axis was set to 3 by force:

chart.xAxis.setLabelCount(3, force: true)
chart.xAxis.avoidFirstLastClippingEnabled = false
chart.xAxis.forceLabelsEnabled = true

class ChartXAxisFormatter: NSObject, IAxisValueFormatter {

    func stringForValue(_ value: Double, axis: AxisBase?) -> String {

        if let index = axis?.entries.firstIndex(of: value), let count = axis?.entries.count  , index == count - 2 {
            return "Now"
        }

        let dateFormatterPrint = DateFormatter()
        dateFormatterPrint.dateFormat = "HH:mm:ss"

        let date = Date(timeIntervalSince1970: value)
        let time = dateFormatterPrint.string(from: date)

            return time
      }
}