getRangeDecoration function

BoxDecoration getRangeDecoration({ required BuildContext context, required int i, required int? rangeStart, required int? rangeEnd, BoxDecoration? defaultDecoration, required Color baseColor, })

Returns a BoxDecoration for a date cell based on its position in a selected date range.

This function applies custom styling depending on whether the date i is:

• The start of the selected range
• The end of the selected range
• Within the selected range (but not start or end)

If the date is not within the range, it returns a default fallback decoration.

Parameters:

• context: The build context (can be used for theme access if needed).
• i: The day of the month (1-based).
• rangeStart: The starting day of the selected range.
• rangeEnd: The ending day of the selected range.
• defaultDecoration: The fallback decoration to use when not in range.
• baseColor: The color used for range highlight decorations.

Returns:

A BoxDecoration customized based on the range position.

Implementation

BoxDecoration getRangeDecoration({
  required BuildContext context,
  required int i,
  required int? rangeStart,
  required int? rangeEnd,
  BoxDecoration? defaultDecoration,
  required Color baseColor,
}) {
  if (rangeStart == rangeEnd) {
    return BoxDecoration(
      color: baseColor.withAlpha(100),
      borderRadius: BorderRadius.circular(32),
    );
  }
  if (i == rangeStart) {
    return BoxDecoration(
      color: baseColor.withAlpha(100),
      borderRadius: const BorderRadius.horizontal(left: Radius.circular(32)),
    );
  }

  if (i == rangeEnd) {
    return BoxDecoration(
      color: baseColor.withAlpha(100),
      borderRadius: const BorderRadius.horizontal(right: Radius.circular(32)),
    );
  }

  if (rangeStart != null &&
      rangeEnd != null &&
      i > rangeStart &&
      i < rangeEnd) {
    return BoxDecoration(
      color: baseColor.withAlpha(100),
      borderRadius: BorderRadius.zero,
    );
  }

  return defaultDecoration ??
      BoxDecoration(
        color: Colors.transparent,
        borderRadius: BorderRadius.circular(6),
      );
}