issue_109983 (c)

main.dart

import 'package:flutter/material.dart';

void main() => runApp(const MaterialApp(home: MyHomePage()));

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key});

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  late final ValueNotifier<List<String>> _notifier;
  late final ScrollController _controller;

  @override
  void initState() {
    _notifier = ValueNotifier([])..addListener(_onAdded);
    _controller = ScrollController();
    super.initState();
  }

  @override
  void dispose() {
    _notifier
      ..removeListener(_onAdded)
      ..dispose();
    _controller.dispose();
    super.dispose();
  }

  void _onAdded() =>
      WidgetsBinding.instance.addPostFrameCallback((_) => _controller.animateTo(
            _controller.position.maxScrollExtent,
            duration: kThemeAnimationDuration,
            curve: Curves.easeOut,
          ));

  void _add() =>
      _notifier.value = [..._notifier.value, '${_notifier.value.length}'];

  @override
  Widget build(context) => Scaffold(
        appBar: AppBar(title: const Text('AppBar')),
        body: LayoutBuilder(
          builder: (context, contraints) => ListView(
            controller: _controller,
            children: [
              const Text('header'),
              SizedBox(
                height: contraints.maxHeight * .9,
                child: const ColoredBox(
                  color: Colors.green,
                  child: Text('body'),
                ),
              ),
              const Text('footer'),
              MyListView(notifier: _notifier),
            ],
          ),
        ),
        floatingActionButton: FloatingActionButton(
          onPressed: _add,
          child: const Icon(Icons.add),
        ),
      );
}

class MyListView extends StatelessWidget {
  final ValueNotifier<List<String>> notifier;
  const MyListView({
    required this.notifier,
    super.key,
  });

  @override
  Widget build(context) => ValueListenableBuilder<List<String>>(
        valueListenable: notifier,
        builder: (context, strings, child) => Column(
          children: [for (final string in strings) Text(string)],
        ),
      );
}