Many Gradient Fill in same lineChart Swift for iOS-Charts

Question

let gradientColors = [UIColor.cyanColor().CGColor, UIColor.clearColor().CGColor] // Colors of the gradient
let colorLocations:[CGFloat] = [1.0, 0.0] // Positioning of the gradient
let gradient = CGGradientCreateWithColors(CGColorSpaceCreateDeviceRGB(), gradientColors, colorLocations) // Gradient Object
set.fill = ChartFill.fillWithLinearGradient(gradient!, angle: 90.0) // Set the Gradient
set.drawFilledEnabled = true // Draw the Gradient

Result

I want to have many fill depending of xAxis value like this :

It's possible to do this ??

Solution:

The solution is to use many dataset, from the second one, the first value for each data need to be same the last value of the previous dataset so at the end it will look like you have one dataset

ex:

let dollars1 = [1453.0,2352,5431,1442] // last value = first value of next dataset
let dollars2 = [1442.0,2234,8763,4453] // last value = first value of next dataset
let dollars3 = [4453.0,3456,7843,5678] // last value = first value of next dataset

func setChartData(months : [String]) {

    var yVals1 : [ChartDataEntry] = [ChartDataEntry]()
    for var i = 0; i < months.count; i++ {
        yVals1.append(ChartDataEntry(value: dollars1[i], xIndex: i))
    }

    let set1: LineChartDataSet = LineChartDataSet(yVals: yVals1, label: "First Set")
    set1.axisDependency = .Left // Line will correlate with left axis values
    set1.setColor(UIColor.redColor().colorWithAlphaComponent(0.5))
    set1.setCircleColor(UIColor.redColor())
    set1.lineWidth = 2.0
    set1.circleRadius = 6.0
    set1.fillAlpha = 1
    set1.fillColor = UIColor.redColor()
    set1.drawFilledEnabled = true

    var yVals2 : [ChartDataEntry] = [ChartDataEntry]()
    for var i = 0; i < months.count; i++ {
        yVals2.append(ChartDataEntry(value: dollars2[i], xIndex: i))
    }

    let set2: LineChartDataSet = LineChartDataSet(yVals: yVals2, label: "Second Set")
    set2.axisDependency = .Left // Line will correlate with left axis values
    set2.setColor(UIColor.greenColor().colorWithAlphaComponent(0.5))
    set2.setCircleColor(UIColor.greenColor())
    set2.lineWidth = 2.0
    set2.circleRadius = 6.0
    set2.fillAlpha = 1
    set2.fillColor = UIColor.greenColor()
    set2.drawFilledEnabled = true

    var yVals3 : [ChartDataEntry] = [ChartDataEntry]()
    for var i = 0; i < months.count; i++ {
        yVals3.append(ChartDataEntry(value: dollars3[i], xIndex: i))
    }

    let set3: LineChartDataSet = LineChartDataSet(yVals: yVals3, label: "Second Set")
    set3.axisDependency = .Left // Line will correlate with left axis values
    set3.setColor(UIColor.blueColor().colorWithAlphaComponent(0.5))
    set3.setCircleColor(UIColor.blueColor())
    set3.lineWidth = 2.0
    set3.circleRadius = 6.0
    set3.fillAlpha = 65 / 255.0
    set3.fillColor = UIColor.blueColor()
    set3.drawFilledEnabled = true

    //3 - create an array to store our LineChartDataSets
    var dataSets : [LineChartDataSet] = [LineChartDataSet]()
    dataSets.append(set1)
    dataSets.append(set2)
    dataSets.append(set3)

    //4 - pass our months in for our x-axis label value along with our dataSets
    let data: LineChartData = LineChartData(xVals: months, dataSets: dataSets)
    data.setValueTextColor(UIColor.whiteColor())

    //5 - finally set our data
    self.lineChartView.data = data

}

Answer 1

Yes its possible to do that gradient fill you want ,just replace below line and add some color so you can check.

set.fill = ChartFill.fillWithLinearGradient(gradient!, angle: 90.0)

Set the angle 180 so it will work

set.fill = ChartFill.fillWithLinearGradient(gradient!, angle: 180.0)