extent property
The total extent of this axis.
It is the sum of the extents of all headers, custom sized or not.
Implementation
late final double extent = (() {
var customSizesCount = 0;
final allCustomSizes = _customSizedHeaders.entries.fold<double>(
0.0,
(value, entry) {
if (entry.key >= totalCount) {
return value;
}
customSizesCount++;
return value + (entry.value.effectiveExtent);
},
);
final allRegularSizes =
(totalCount - customSizesCount) * defaultHeaderExtent;
return allCustomSizes + allRegularSizes;
})();