iOS Charts 3 - Align X Labels (dates) with plots - charts

Question

I have found a similar question on here, but the answer did not help me. I think due to my data structure.
I have an array made up of individual arrays, each for its own line in the chart. this is then made up of multiple structs for the plot points of that line.
My issue is that values/lines are correct, but are not aligning correctly with the dates. In the example below. the dates start at 3rd May and end 8th May. Please help
here is my code
struct chartPoint {
let date:String
var total:Double
let exercise:String
}
var sets:[[chartPoint]] = []
func setupLineChart() {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
var dataSets:[LineChartDataSet] = []
var color:[UIColor] = [UIColor.red,UIColor.blue, UIColor.green,UIColor.red,UIColor.red,UIColor.red,UIColor.red]
for i in sets { //Array of array of structs
let sort = i.sorted { // sort the internal array by date
item1, item2 in
let date1 = dateFormatter.date(from:item1.date)
let date2 = dateFormatter.date(from:item2.date)
return date1!.compare(date2!) == ComparisonResult.orderedAscending
}
var dataEntries: [ChartDataEntry] = []
for stat in 0...(sort.count - 1) {
let date = dateFormatter.date(from:sort[stat].date)
let timeIntervalForDate: TimeInterval = date!.timeIntervalSince1970
let dataEntry = ChartDataEntry(x: Double(timeIntervalForDate), y: sort[stat].total)
dataEntries.append(dataEntry)
if stat == (sort.count - 1){
let chartDataSet = LineChartDataSet(values: dataEntries, label: "\(sort[stat].exercise)")
chartDataSet.setCircleColor(color[stat])
chartDataSet.setColor(color[stat], alpha: 1.0)
chartDataSet.drawValuesEnabled = true
dataSets.append(chartDataSet)
startChart(dataSets: dataSets)
}
}
}
}
func startChart(dataSets:[LineChartDataSet]){
testLineChartView.animate(xAxisDuration: 0.7, yAxisDuration: 0.7)
testLineChartView.dragEnabled = true
testLineChartView.legend.form = .circle
testLineChartView.drawGridBackgroundEnabled = false
let xaxis = testLineChartView.xAxis
xaxis.valueFormatter = axisFormatDelegate
xaxis.labelCount = dataSets.count
xaxis.granularityEnabled = true
xaxis.granularity = 1.0
xaxis.centerAxisLabelsEnabled = true
xaxis.avoidFirstLastClippingEnabled = true
xaxis.drawLimitLinesBehindDataEnabled = true
let rightAxis = testLineChartView.rightAxis
rightAxis.enabled = false
let leftAxis = testLineChartView.leftAxis
leftAxis.drawZeroLineEnabled = true
leftAxis.drawGridLinesEnabled = true
axisFormatDelegate = self
testLineChartView.delegate = self
let chartData = LineChartData(dataSets: dataSets)
testLineChartView.data = chartData
testLineChartView.chartDescription?.text = ""
}
extension ChartViewController: IAxisValueFormatter {
func stringForValue(_ value: Double, axis: AxisBase?) -> String {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "dd MMM"
let date = Date(timeIntervalSince1970: value)
return dateFormatter.string(from: date)
}
}

Answer 1

I am using dates on the x-axis as well in one of my projects and I simply changed each date to a string and passed an array of string values to an IndexAxisValueFormatter.
testLineChartView.xAxis.valueFormatter = IndexAxisValueFormatter(values: xvalues)
If this is not what you are looking for, can you show a sample of what "sets" includes? Then I will be able to run your code.

Answer 2

Here is another thread I started with an issue around a single value not showing. It includes the code that also fixed this.
I think the main point being
xaxis.forceLabelsEnabled = true
iOS Charts - single values not showing Swift