buildUpdatedItemWidget method
Implementation
@override
Widget buildUpdatedItemWidget(E newItem) {
assert(updateItemBuilder != null);
// We need to override this method, as AnimatedBuilder is not
// supported as a top-level item widget in reorderable lists.
final value = updateAnimController.value;
final oldItem = changes[newItem];
final item = value < 0.5 ? oldItem : newItem;
return updateItemBuilder!(context, updateAnimation, item!);
}