estimateMaxScrollOffset method Null safety

double estimateMaxScrollOffset(
  1. SliverConstraints constraints,
  2. {int? firstIndex,
  3. int? lastIndex,
  4. double? leadingScrollOffset,
  5. double? trailingScrollOffset}

Called to estimate the total scrollable extents of this object.

Must return the total distance from the start of the child with the earliest possible index to the end of the child with the last possible index.


double estimateMaxScrollOffset(
  SliverConstraints constraints, {
  int? firstIndex,
  int? lastIndex,
  double? leadingScrollOffset,
  double? trailingScrollOffset,