Convert a histogram to a grouped histogram using danielgindi / ios-charts and Swift

Question

I created a simple histogram with a library in https://github.com/danielgindi/ios-charts still can not figure out how to make this grouped histogram, I added an array of units sold to the diagram, but I do not know how to get an array unitBought on a chart to make it grouped using chart.please.

@IBOutlet weak var barChartView: BarChartView! override func viewDidLoad() { super.viewDidLoad() months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"] let unitsSold = [20.0, 4.0, 6.0, 3.0, 12.0, 16.0, 4.0, 18.0, 2.0, 4.0, 5.0, 12.8] let unitsBought = [20.0, 4.0, 6.0, 3.0, 12.0, 16.0, 4.0, 18.0, 2.0, 4.0, 5.0, 12.8] setChart(months, values: unitsSold) } //functions func setChart(dataPoints: [String], values: [Double]) { barChartView.noDataText = "You need to provide data for the chart." var dataEntries: [BarChartDataEntry] = [] for i in 0..<dataPoints.count { let dataEntry = BarChartDataEntry(value: values[i], xIndex: i) dataEntries.append(dataEntry) } let chartDataSet = BarChartDataSet(yVals: dataEntries, label: "Units Sold") let chartData = BarChartData(xVals: months, dataSet: chartDataSet) barChartView.data = chartData barChartView.backgroundColor = UIColor(red: 255/255, green: 255/255, blue: 255/255, alpha: 1) barChartView.gridBackgroundColor = UIColor(red: 255/255, green: 255/255, blue: 255/255, alpha: 1) barChartView.legend.enabled = false barChartView.leftAxis.drawGridLinesEnabled = false barChartView.leftAxis.drawAxisLineEnabled = true barChartView.rightAxis.drawGridLinesEnabled = false barChartView.rightAxis.drawAxisLineEnabled = false barChartView.rightAxis.drawLabelsEnabled = false barChartView.xAxis.drawGridLinesEnabled = false barChartView.xAxis.drawLabelsEnabled = true } 

Answer 1

In fact, you did nothing with unitsBought .

For a bar chart, you can do two things:

• Add another DataSet with unitsBought
• Use another overload of BarCharDataEntry(values: [Double], xIndex: Int) or BarCharDataEntry(values: [Double], xIndex: Int, label: String) to pass multiple values ​​for each record, which makes it complex.

Answer 2

 let months = ["Jan", "Feb", "Mar", "Apr", "May"] let unitsSold = [20.0, 4.0, 6.0, 3.0, 12.0] let unitsBought = [10.0, 14.0, 60.0, 13.0, 2.0] override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib. barChartView.delegate = self barChartView.noDataText = "You need to provide data for the chart." barChartView.chartDescription?.text = "sales vs bought " //legend let legend = barChartView.legend legend.enabled = true legend.horizontalAlignment = .right legend.verticalAlignment = .top legend.orientation = .vertical legend.drawInside = true legend.yOffset = 10.0; legend.xOffset = 10.0; legend.yEntrySpace = 0.0; let xaxis = barChartView.xAxis xaxis.valueFormatter = axisFormatDelegate xaxis.drawGridLinesEnabled = true xaxis.labelPosition = .bottom xaxis.centerAxisLabelsEnabled = true xaxis.valueFormatter = IndexAxisValueFormatter(values:self.months) xaxis.granularity = 1 let leftAxisFormatter = NumberFormatter() leftAxisFormatter.maximumFractionDigits = 1 let yaxis = barChartView.leftAxis yaxis.spaceTop = 0.35 yaxis.axisMinimum = 0 yaxis.drawGridLinesEnabled = false barChartView.rightAxis.enabled = false //axisFormatDelegate = self setChart() } func setChart() { barChartView.noDataText = "You need to provide data for the chart." var dataEntries: [BarChartDataEntry] = [] var dataEntries1: [BarChartDataEntry] = [] for i in 0..<self.months.count { let dataEntry = BarChartDataEntry(x: Double(i) , y: self.unitsSold[i]) dataEntries.append(dataEntry) let dataEntry1 = BarChartDataEntry(x: Double(i) , y: self.self.unitsBought[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: "Unit sold") let chartDataSet1 = BarChartDataSet(values: dataEntries1, label: "Unit Bought") let dataSets: [BarChartDataSet] = [chartDataSet,chartDataSet1] chartDataSet.colors = [UIColor(red: 230/255, green: 126/255, blue: 34/255, 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.months.count let startYear = 0 chartData.barWidth = barWidth; barChartView.xAxis.axisMinimum = Double(startYear) let gg = chartData.groupWidth(groupSpace: groupSpace, barSpace: barSpace) print("Groupspace: \(gg)") barChartView.xAxis.axisMaximum = Double(startYear) + gg * Double(groupCount) chartData.groupBars(fromX: Double(startYear), groupSpace: groupSpace, barSpace: barSpace) //chartData.groupWidth(groupSpace: groupSpace, barSpace: barSpace) barChartView.notifyDataSetChanged() barChartView.data = chartData //background color barChartView.backgroundColor = UIColor(red: 189/255, green: 195/255, blue: 199/255, alpha: 1) //chart animation barChartView.animate(xAxisDuration: 1.5, yAxisDuration: 1.5, easingOption: .linear) } 

Answer 3

 func setChartBarGroupDataSet(dataPoints: [String], values: [Double], values2: [Double],sortIndex:Int) { var dataEntries: [BarChartDataEntry] = [] var dataEntries2: [BarChartDataEntry] = [] for i in 0..<dataPoints.count { let dataEntry = BarChartDataEntry(value: values[i], xIndex: i) dataEntries.append(dataEntry) } for i in 0..<dataPoints.count { let dataEntry = BarChartDataEntry(value: values2[i], xIndex: i) dataEntries2.append(dataEntry) } let chartDataSet = BarChartDataSet(yVals: dataEntries, label: " ") let chartDataSet2 = BarChartDataSet(yVals: dataEntries2, label: " ") chartDataSet2.colors = [UIColor(red: 255/255, green: 70/255, blue: 108/255, alpha: 1)] chartDataSet.colors = [UIColor(red: 49/255, green: 27/255, blue: 146/255, alpha: 1)] let dataSets: [BarChartDataSet] = [chartDataSet,chartDataSet2] let data = BarChartData(xVals: dataPoints, dataSets: dataSets) barChartView.data = data barChartView.descriptionText = "" barChartView.rightAxis.drawGridLinesEnabled = false barChartView.rightAxis.drawAxisLineEnabled = false barChartView.rightAxis.drawLabelsEnabled = false barChartView.animate(xAxisDuration: 2.0, yAxisDuration: 2.0, easingOption: .EaseInBounce) }