[ios] ValueListenableBuilder rebuild interrupts ongoing scroll gesture #173225
Description
Steps to reproduce
- Have a ValueListenableBuilder inside SingleChildScrollView.
- Scroll so much that there is rubber banding effect.
- Keep finger on display to "over scroll".
- When ValueNotifier value changes ValueListenableBuilder builds, scrolling is ended and causes ScrollView to go to begining(or end) of view.
Expected results
When ValueListenableBuilder rebuilds, scrolling should continue seamlessly.
Actual results
Scroll gesture ends when ValueListenableBuilder rebuilds.
Code sample
Code sample
import 'package:flutter/material.dart';
import 'dart:async';
class MainApp extends StatefulWidget {
const MainApp({super.key});
@override
State<MainApp> createState() => _MainAppState();
}
class _MainAppState extends State<MainApp> {
final titleValue = ValueNotifier<String>('0');
int counter = 0;
@override
void initState() {
super.initState();
Timer.periodic(const Duration(milliseconds: 1500), (timer) {
counter++;
titleValue.value = counter.toString();
});
}
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
body: SingleChildScrollView(
child: ConstrainedBox(
constraints: BoxConstraints(
minHeight: MediaQuery.sizeOf(context).height * 1.2,
),
child: Column(
children: [
const SizedBox(height: 300),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
const Text('Time: ', style: TextStyle(color: Colors.red)),
ValueListenableBuilder(
valueListenable: titleValue,
builder: (context, value, child) {
return Text(
value,
style: const TextStyle(
color: Colors.blue,
fontFeatures: [FontFeature.tabularFigures()],
),
);
},
),
],
),
Container(width: 200, height: 200, color: Colors.blue),
],
),
),
),
),
);
}
}
void main() {
runApp(const MainApp());
}
Screenshots or Video
Screenshots / Video demonstration
example.mp4
Logs
Flutter Doctor output
Doctor output
[✓] Flutter (Channel stable, 3.32.8, on macOS 15.6 24G84 darwin-arm64, locale en-US) [257ms]
• Flutter version 3.32.8 on channel stable at /Users/mm/Coding/flutter/flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision edada7c56e (10 days ago), 2025-07-25 14:08:03 +0000
• Engine revision ef0cd00091
• Dart version 3.8.1
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• Java version OpenJDK Runtime Environment (build 21.0.6+-13368085-b895.109)
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• Xcode at /Applications/Xcode.app/Contents/Developer
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• Flutter plugin can be installed from:
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• Java version OpenJDK Runtime Environment (build 21.0.6+-13368085-b895.109)
[✓] VS Code (version 1.102.3) [8ms]
• VS Code at /Applications/Visual Studio Code.app/Contents
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[✓] Connected device (4 available) [5.7s]
• GoldenEye (2) (wireless) (mobile) • 00008110-000279691122801E • ios • iOS 18.6 22G86
• iPhone 16 (mobile) • AC5080C6-540F-4CBD-B01C-FC0146903FC7 • ios • com.apple.CoreSimulator.SimRuntime.iOS-18-5 (simulator)
• macOS (desktop) • macos • darwin-arm64 • macOS 15.6 24G84 darwin-arm64
• Chrome (web) • chrome • web-javascript • Google Chrome 138.0.7204.184
[✓] Network resources [262ms]
• All expected network resources are available.