in example/lib/preload/ali_sliding_window.dart [112:127]
void moveTo(int position) {
if (position < 0 || position >= _itemList.length) return;
if (_currentIndex == position) return;
final currentWindow = getWindowIndices(position);
if (currentWindow.isEmpty) return;
final previousWindow = getWindowIndices(_currentIndex);
final toLoad = _difference(currentWindow, previousWindow);
final toCancel = _difference(previousWindow, currentWindow);
_processItems(toCancel, _cancelItem);
_processItems(toLoad, _executeItem);
_currentIndex = position;
}