This package provides the scroll to index mechanism for fixed/variable row height for Flutter scrollable widget.

In the pubspec.yaml of your flutter project, add the following dependency:

dependencies: ... scroll_to_index: any

In your library add the following import:

import 'package:scroll_to_index/scroll_to_index.dart';

For help getting started with Flutter, view the online documentation.

This is a widget level library, means you can use this mechanism inside any Flutter scrollable widget.

Example for Flutter ListView

ListView( scrollDirection: scrollDirection, controller: controller, children: randomList.map<Widget>((data) { final index = data[0]; final height = data[1]; return AutoScrollTag( key: ValueKey(index), controller: controller, index: index, child: Text('index: $index, height: $height'), highlightColor: Colors.black.withOpacity(0.1), ); }).toList(), ) 

you can wrap any of your row widget which has dynamic row height

AutoScrollTag( key: ValueKey(index), controller: controller, index: index, child: child )

with the AutoScrollController controller.

when you need to trigger scroll to a specified index, you can call

controller.scrollToIndex(index, preferPosition: AutoScrollPosition.begin) 

even more, with a fixed row height, you can give it a suggested height for more efficient scrolling. there are more configuration.

final controller = AutoScrollController( //add this for advanced viewport boundary. e.g. SafeArea viewportBoundaryGetter: () => Rect.fromLTRB(0, 0, 0, MediaQuery.of(context).padding.bottom), //choose vertical/horizontal axis: scrollDirection, //this given value will bring the scroll offset to the nearest position in fixed row height case. //for variable row height case, you can still set the average height, it will try to get to the relatively closer offset //and then start searching. suggestedRowHeight: 200 ); 

for full example, please see this Demo.

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