Building a pie chart
We know that a pie chart is a way to represent proportional numeric values, using slices that form a circle—a pie.
With a pie chart being made up of a slice and a circle – simple geometric shapes – it is simple enough to implement them in SwiftUI.
This recipe will use a dataset on the number of pets in three different European cities.
Getting ready
This recipe doesn't have any external resources, so it is enough just to create a SwiftUI project called PieChartApp
.
How to do it...
This recipe is slightly more complicated than usual because it has two main parts:
- Manipulating datapoints
- Visualizing datapoints
Regarding the datapoints, given the list of data, we must scale the value to adapt to the maximum, meaning that we must calculate the maximum value in the series and then scale the other values so that each value can fit the pie chart. Also, we must calculate the angles for each slice – the...