[ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: 'package:flutter/src/widgets/animated_scroll_view.dart': Failed assertion: line 1082 pos 12: 'itemIndex >= 0 && itemIndex < _itemsCount': is not true.

This error occurs in the Flutter framework when using the AnimatedScrollView widget and passing an invalid index value for the itemsCount parameter. The itemsCount parameter represents the total number of items in the scrollable list, and the itemIndex parameter represents the index of the currently selected item.

To fix this error, ensure that the itemIndex value is within the valid range of 0 to (_itemsCount - 1). Also, make sure that the _itemsCount value is correctly initialized and updated when adding or removing items from the scrollable list.