willDetachRenderer method
A render object previously associated with this Node will be / has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderer.
Implementation
@override
void willDetachRenderer([flutter.RenderObjectElement? flutterWidgetElement]) {
super.willDetachRenderer(flutterWidgetElement);
// Remove all intersection change listeners.
renderStyle.clearIntersectionChangeListeners(flutterWidgetElement);
}