core-plot swift version of barFillForPlotColor - core-plot

Question

Good day to all of you;
I have recently started working with CorePlot in my iOS projects and have learned how to create bar charts from my data (thank you RayWenderlich tutorial).
Now, rather than using one colour for all the bars I would like to colour them based on their values. For example, values below 1.0 are red, values of 1.0 are blue, and values above 1.0 are green.
I know this can be done and I have read numerous articles that talk about using the -(nullable CPTFill *)barFillForBarPlot:(nonnull CPTBarPlot *)barPlot recordIndex:(NSUInteger)index function. In fact I have looked at the coloredBarChart example in the CorePlot Examples - Plot Gallery and see how they are using this function. The problem I am having is that I am programming in Swift and need to have a Swift version of this function that I can use, or an explanation of how I can use this version in my Swift code.
Any assistance that you can provide is greatly appreciated.

Answer 1

The Swift compiler automatically renames Objective-C methods to make them more "Swifty". Try this in the bar plot datasource:
func barFill(for plot: CPTBarPlot, record: UInt) -> CPTFill?
{
return CPTFill(color: .red()) // or whatever color you want based on the data value
}

Answer 2

Ah, I see; the function call gets converted to be Swift like. Based on that information I was able to take a look at some Swift calls I was already using from CorePlot and the associated Objective C code to figure out how to convert it.
This is what I came up with:
// original function
-(nullable CPTFill *)barFillForBarPlot:(nonnull CPTBarPlot *)barPlot recordIndex:(NSUInteger)index
{
return CPTFill(color: .red()) // or whatever color you want based on the data value
}
// Swift version of the function (updated 2018/Oct(10)/07)
func barFill(for barPlot: CPTBarPlot, record index: UInt ) -> CPTFill?
{
return CPTFill(color: .red()) // or whatever color you want based on the data value
}
Thanks Eric.