SciChart iOS Date on line chart

Question

I'm having trouble appending the date to my SciChart line chart. I'm getting this error at runtime.

Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Axis does not support type.'

I'm following along with the supplied examples, here is my code to append my data to the axis.

var sciChartSurface: SCIChartSurface?

var lineDataSeries: SCIXyDataSeries!

var lineRenderableSeries: SCIFastLineRenderableSeries!

func createDataSeries(){

    lineDataSeries = SCIXyDataSeries(xType: .dateTime, yType: .double)

    lineDataSeries.acceptUnsortedData = true

    let items = self.dataFeed.priceHistory

    let dateFormatter = DateFormatter()

    dateFormatter.dateFormat = "yyyy-MM-dd"

    for i in 0..<(items.count) - 1 {

        let date:Date = dateFormatter.date(from: items[i].date!)!
        print("\(date) \(items[i].close!)")
        lineDataSeries.appendX(SCIGeneric(date), y: SCIGeneric(Double(items[i].close!)))
    }
}

this is what my output from the print statement

2017-08-09 07:00:00 +0000 2474.02
2017-08-08 07:00:00 +0000 2474.92
2017-08-07 07:00:00 +0000 2480.91
2017-08-04 07:00:00 +0000 2476.83
2017-08-03 07:00:00 +0000 2472.16
2017-08-02 07:00:00 +0000 2477.57

Any idea what I'm doing wrong? Glad to include the entire ViewController if needed.

Answer 1

the error was in how I set up the axix and it must be set up as a datetimeaxis....

func setUpUI() {
    // Create a SCIChartSurface. This is a UIView so can be added directly to the UI
    sciChartSurface = SCIChartSurface(frame: self.view.bounds)
    sciChartSurface?.translatesAutoresizingMaskIntoConstraints = true

    // Add the SCIChartSurface as a subview
    self.view.addSubview(sciChartSurface!)

    // Create an XAxis and YAxis. This step is mandatory before creating series
    sciChartSurface?.xAxes.add(SCIDateTimeAxis())
    sciChartSurface?.yAxes.add(SCINumericAxis())
}