ios charts not displaying line/bar in charts - ios

Question

I am working on ios-charts by Daniel Gindi on swift 3.0. I have written following code for bar charts
var dataEntries: [BarChartDataEntry] = []
for i in 0..<dateTime.count {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "MM/dd/yyyy hh:mm:ss aa"
let dateObj = dateFormatter.date(from: dateTime[i])
let timeIntervalForDate = dateObj!.timeIntervalSince1970
let dataEntry = BarChartDataEntry(x: Double(timeIntervalForDate), y: Double(readings[i]))
dataEntries.append(dataEntry)
}
let chartDataSet = BarChartDataSet(values: dataEntries, label: "Units")
let chartData = BarChartData(dataSet: chartDataSet)
self.ChartsView.data = chartData
i get following result in emulator:
you can see no red line reflecing my values. I even zoomed to charts but nothing was shown.
I also tried line chart with sample values. Here is the code:
let dollars1 = [20.0, 4.0, 6.0, 3.0, 12.0, 16.0, 4.0, 18.0, 2.0, 4.0, 5.0, 4.0]
let months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
var yValues : [ChartDataEntry] = [ChartDataEntry]()
for i in 0 ..< months.count {
yValues.append(ChartDataEntry(x: Double(i + 1), y: dollars1[i]))
}
let LineData = LineChartData()
let ds = LineChartDataSet(values: yValues, label: "Months")
LineData.addDataSet(ds)
self.ChartsView.data = LineData
Its result is even more weird. No grid lines are shown either in this chart. Here is the image.
I am not sure what is wrong with these graphs. Am I missing something. So far i am unable to look any furthur as most solutions are using old version of charts(or may be it is something else i am not aware). Please guide me to proper direction. Thanks

Answer 1

I am struggling with Version 3.0 and Swift 3 and the lack of documentation... May I point you to the best text on the subject which can be found here
Xvals as Parameters are gone, instead you use two-dimensional data on axis
Regarding your problem with timevalues.. you could use the "timeIntervalSince1970" of the date-object and format things with an extension
return dateFormatter.string(from: Date(timeIntervalSince1970: value))
all of which is to be found at the link mentioned above

Answer 2

There is a bug in ios-charts try to use index of timestamp rather than using timestamp or date to show on the x-axis.
// i is the index of that timestamp in data.
let dataEntry = BarChartDataEntry(x: i, y: Double(readings[i]))

Answer 3

hey nothing is disabled in iOS charts everything is working fine..Here is the code that I have used in my app to display horizontal chart as well as vertical chart hope it helps to anyone who is stucked on IOS chart...stay tune with StackOverflow... enjoy coding :)
import UIKit
import Charts
class DashboardViewController: UIViewController, ChartViewDelegate
{
#IBOutlet weak var barview: BarChartView!
#IBOutlet weak var horizontalview: HorizontalBarChartView!
var attendencelabels = [String]()
let Present = [60.0, 60.0]
let Absent = [20.0,40.0]
var subjects : [String]!
var maxUnits : Double!
override func viewDidLoad() {
super.viewDidLoad()
barview.delegate = self
barview.noDataText = "You need to provide data for the chart."
barview.chartDescription?.text = ""
attendencelabels.append("March")
attendencelabels.append("April")
subjects = ["Physics","Chemistry","Biology","English","Maths"]
horizontalview.delegate = self
var marks = [60.0,70.0,60.0,80.0,90.0]
maxUnits = marks.max()
setHorizontalChart(dataPoints: subjects, values: marks)
//legend
let legend = barview.legend
legend.enabled = true
legend.horizontalAlignment = .center
legend.verticalAlignment = .bottom
legend.orientation = .horizontal
legend.drawInside = false
legend.yOffset = 10.0;
legend.xOffset = 10.0;
legend.yEntrySpace = 0.0;
let xaxis = barview.xAxis
xaxis.valueFormatter = DefaultAxisValueFormatter.self as! IAxisValueFormatter
xaxis.drawGridLinesEnabled = true
xaxis.labelPosition = .top
xaxis.centerAxisLabelsEnabled = true
xaxis.valueFormatter = IndexAxisValueFormatter(values:self.attendencelabels)
xaxis.granularity = 1
let leftAxisFormatter = NumberFormatter()
leftAxisFormatter.maximumFractionDigits = 1
let yaxis = barview.leftAxis
yaxis.spaceTop = 0.35
yaxis.axisMinimum = 0
yaxis.drawGridLinesEnabled = false
barview.rightAxis.enabled = false
setChart()
}
func setChart() {
barview.noDataText = "You need to provide data for the chart."
var dataEntries: [BarChartDataEntry] = []
var dataEntries1: [BarChartDataEntry] = []
for i in 0..<self.attendencelabels.count
{
let dataEntry = BarChartDataEntry(x: Double(i) , y: self.Present[i])
dataEntries.append(dataEntry)
let dataEntry1 = BarChartDataEntry(x: Double(i) , y: self.self.Absent[i])
dataEntries1.append(dataEntry1)
//stack barchart
//let dataEntry = BarChartDataEntry(x: Double(i), yValues: [self.unitsSold[i],self.unitsBought[i]], label: "groupChart")
}
let chartDataSet = BarChartDataSet(values: dataEntries, label: "Working Days")
let chartDataSet1 = BarChartDataSet(values: dataEntries1, label: "Present Days")
let dataSets: [BarChartDataSet] = [chartDataSet,chartDataSet1]
chartDataSet.colors = [UIColor(red: 0/255, green: 255/255, blue: 25/255, alpha: 1)]
chartDataSet1.colors = [UIColor(red: 255/255, green: 0/255, blue: 61/255, alpha: 1)]
//chartDataSet.colors = ChartColorTemplates.colorful()
//let chartData = BarChartData(dataSet: chartDataSet)
let chartData = BarChartData(dataSets: dataSets)
let groupSpace = 0.3
let barSpace = 0.05
let barWidth = 0.3
// (0.3 + 0.05) * 2 + 0.3 = 1.00 -> interval per "group"
let groupCount = self.attendencelabels.count
let startYear = 0
chartData.barWidth = barWidth;
barview.xAxis.axisMinimum = Double(startYear)
let gg = chartData.groupWidth(groupSpace: groupSpace, barSpace: barSpace)
print("Groupspace: \(gg)")
barview.xAxis.axisMaximum = Double(startYear) + gg * Double(groupCount)
chartData.groupBars(fromX: Double(startYear), groupSpace: groupSpace, barSpace: barSpace)
//chartData.groupWidth(groupSpace: groupSpace, barSpace: barSpace)
barview.notifyDataSetChanged()
barview.data = chartData
//background color
barview.backgroundColor = UIColor.white
//chart animation
barview.animate(xAxisDuration: 1.5, yAxisDuration: 1.5, easingOption: .linear)
}
func setHorizontalChart(dataPoints: [String], values: [Double]) {
horizontalview.noDataText = "You need to provide data for the chart."
let formato: horizontalbarformatter = horizontalbarformatter()
let xaxiss: XAxis = XAxis()
var dataEntriesss: [BarChartDataEntry] = []
for i in 0..<dataPoints.count {
let dataEntryy = BarChartDataEntry(x: Double(Int(i)), y: values[i])
dataEntriesss.append(dataEntryy)
formato.stringForValue(Double(i), axis: xaxiss)
}
xaxiss.valueFormatter = formato
let chartHorizontalDataSet = BarChartDataSet(values: dataEntriesss, label: "Marks")
let horizontalchartData = BarChartData(dataSet: chartHorizontalDataSet)
chartHorizontalDataSet.colors = ChartColorTemplates.colorful()
horizontalview.xAxis.valueFormatter = xaxiss.valueFormatter
horizontalview.data = horizontalchartData
horizontalview.backgroundColor = UIColor.white
horizontalview.descriptionText = ""
horizontalview.xAxis.labelPosition = .bottom
horizontalview.leftAxis.axisMinimum = 0
horizontalview.leftAxis.axisMaximum = maxUnits + 1
//barChartView.animate(xAxisDuration: 2.0, yAxisDuration: 2.0)
horizontalview.animate(xAxisDuration: 2.0, yAxisDuration: 2.0, easingOption: .easeInBounce)
let ll = ChartLimitLine(limit: 10.0, label: "Target")
horizontalview.rightAxis.addLimitLine(ll)
}
func chartValueSelected(chartView: ChartViewBase, entry: ChartDataEntry, highlight: Highlight) {
print("\(entry.y) in \(attendencelabels[Int(entry.x)])")
}
}