maxScrollObstructionExtentBefore method
- @override
override
Returns the total scroll obstruction extent of all slivers in the viewport
before child.
This is the extent by which the actual area in which content can scroll is reduced. For example, an app bar that is pinned at the top will reduce the area in which content can actually scroll by the height of the app bar.
Implementation
@override
double maxScrollObstructionExtentBefore(RenderSliver child) {
assert(child.parent == this);
assert(child.constraints.growthDirection == GrowthDirection.forward);
double pinnedExtent = 0.0;
RenderSliver current = firstChild;
while (current != child) {
pinnedExtent += current.geometry.maxScrollObstructionExtent;
current = childAfter(current);
}
return pinnedExtent;
}