Custom legends in Swift Charts for iOS 16 - swift

Question

How do I obtain colour imagery, or more generally, styling information for each legend entry to construct a custom legend in a chart in Swift Charts?
I have a chart here, with a legend positioned on the right, but using the content: argument of chartLegend does not pass any info into the closure to use. I would like to wrap the legend into a scroll view, so when there are too many entries, the chart will appear correctly on the screen, and the user can scroll through the legend below the chart.
Chart(points, id: \.self) { point in
LineMark(
x: .value("time/s", point.timestamp),
y: .value("potential/mV", point.potential)
)
.foregroundStyle(by: .value("Electrode", point.electrode.symbol))
}
.chartLegend(position: .bottom)
// ...
Here is the chart with too many legend entries interfering with the chart sizing, resulting in cropping:
And here is the chart with only a few entries so that the chart is sized correctly, with no cropping, and the legend has text to discern between the electrodes they represent:
Any help is much appreciated.

Answer 1

Not scrolling but the chart legend can be placed on the side with code like this:
.chartLegend(position: .trailing, alignment: .top)
This gives more room for a legend. The legend won't scroll but all the items will be listed even if going past the end of the chart. The frame height can be increased. The example shows a before(default) and after(using the code above).
The colors can be assigned manually using the chartForegroundStyleScale like this after the end of the chart:
.chartForegroundStyleScale([
"Hong Kong": Color.green,
"London": Color.red,
"Taipei": Color.purple,
"New York": Color.teal,
"Paris": Color.pink,
"Sydney": Color.orange
])
Symbols can be created based on the series:
.symbol(by: .value("City", series.city))