getLayout method

  1. @override
SliverGridLayout getLayout (SliverConstraints constraints)
override

Returns information about the size and position of the tiles in the grid.

Implementation 

@override
SliverGridLayout getLayout(SliverConstraints constraints) {
  assert(_debugAssertIsValid());
  final int crossAxisCount = (constraints.crossAxisExtent / (maxCrossAxisExtent + crossAxisSpacing)).ceil();
  final double usableCrossAxisExtent = constraints.crossAxisExtent - crossAxisSpacing * (crossAxisCount - 1);
  final double childCrossAxisExtent = usableCrossAxisExtent / crossAxisCount;
  final double childMainAxisExtent = childCrossAxisExtent / childAspectRatio;
  return SliverGridRegularTileLayout(
    crossAxisCount: crossAxisCount,
    mainAxisStride: childMainAxisExtent + mainAxisSpacing,
    crossAxisStride: childCrossAxisExtent + crossAxisSpacing,
    childMainAxisExtent: childMainAxisExtent,
    childCrossAxisExtent: childCrossAxisExtent,
    reverseCrossAxis: axisDirectionIsReversed(constraints.crossAxisDirection),
  );
}