Show loading indicator while graph is loading in Highcharts - ios

Question

I am generating a graph using Highcharts framework in one of the iOS projects using Swift language.
The function for generating graph is as follows.
private func createBUGraph()
{
let chartView = HIChartView(frame: self.chartHolderViewOutlet.bounds)
let options = HIOptions()
let title = HITitle()
title.text = "UTS"
options.title = title
let subtitle = HISubtitle()
subtitle.text = "Sales & Margin"
options.subtitle = subtitle
let xAxis = HIXAxis()
xAxis.categories = ["A", "B", "C", "D"]//
options.xAxis = [xAxis]
let yAxis = HIYAxis()
//yAxis.min = 0
yAxis.title = HITitle()
yAxis.title.text = "Sales"
yAxis.lineWidth = 1
let y2Axis = HIYAxis()
y2Axis.title = HITitle()
y2Axis.title.text = "Margin"
y2Axis.lineWidth = 1
y2Axis.tickPositions = [5,10,15,20]
y2Axis.opposite = true
options.yAxis = [yAxis,y2Axis]
let Sales = HIColumn()
Sales.name = "Sales"
Sales.data = [3, 2, 1, 3]
let SalesForecast = HIColumn()
SalesForecast.name = "Sales Forecast"
SalesForecast.data = 2, 3, 5, 7]
let Margin = HISeries()
Margin.name = "Margin"
Margin.data = [2.5, 1.2, 8.5, 5.5]
Margin.marker = HIMarker()
Margin.marker.lineWidth = 2
Margin.marker.symbol = "circle"
let MarginForeast = HISeries()
MarginForeast.name = "Margin Foreast"
MarginForeast.data = [3, 2.67, 3, 6.33] //
MarginForeast.marker = HIMarker()
MarginForeast.marker.lineWidth = 2
MarginForeast.marker.symbol = "circle"
options.series = [Sales, SalesForecast, Margin, MarginForeast]
chartView.options = options
self.chartHolderViewOutlet.addSubview(chartView)
}
While the graph is being loaded, I need to show a loading indicator in the graph. Is there any way to show that?
Or is there any way to know whether the graph has completed loading or not?
Thanks in advance

Answer 1

Add any loader when ever you call Chart method and stop loader when your charts load.
These are library for loader you can use any other or by default loader by apple.
1.https://github.com/ninjaprox/NVActivityIndicatorView
2.https://github.com/relatedcode/ProgressHUD

Answer 2

You may try this
func createBUGraph(completion: (Bool) -> ()) {
// do stuff here
completion(true)
}
createBUGraph(completion: { (success) -> Void in
// add loader
if success {
print("true")
// hide loader
}
})

Answer 3

You might as well use your own loader and show it when the chart is loading.
Then you can hide it using the chartViewDidLoad function from HIChartViewDelegate
API: https://api.highcharts.com/ios/highcharts/Protocols/HIChartViewDelegate.html#//api/name/chartViewDidLoad