onMove method
Implementation
Future<void> onMove(BuildContext context, int index) async {
int? newIndex = await showMoveTo(context, (value.length), index);
if (newIndex != null && onChanged != null) {
List<ModernFormBottomSheetModel<T>> _v =
List<ModernFormBottomSheetModel<T>>.from(value);
ModernFormBottomSheetModel<T> tmp = _v[index];
_v.removeAt(index);
_v.insert(newIndex, tmp);
onChanged!(_v);
}
}