Request a color scheme change

[jinjee89]

Here is the code to get the default color when activeBgColor is not specified:
final activeBgColor =
widget.activeBgColor ?? [Theme.of(context).primaryColor];
However, changing it to the following would allow for consistency when using a color scheme:
final activeBgColor =
widget.activeBgColor ?? [Theme.of(context).colorScheme.primary];