Hi

Thank you for the great lib 👍 I found that this comment is not working. https://github.com/idootop/custom_nested_scroll_view/blob/main/lib/src/nested_scroll_view.dart#L341

To implement infinite scroll loading I wanted to obtain the inner scrolling state so I wanted to access _NestedScrollViewState.

What I wanted to do was:

final GlobalKey<CustomNestedScrollViewState> documentsNestedKey = GlobalKey();

@override
void initState() {
  WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
    documentsNestedKey.currentState!.innerController.addListener(() {
      print("Scrolling nested scrollview. ${documentsNestedKey.currentState!.innerController.positions}");
      print("Now we can do infinite scroll loading!");
    });
  }
}

@override
Widget build(BuildContext context) {
  return CustomNestedScrollView(
    key:  documentsNestedKey,
    ...
  );
}

Please look into it if you like ✋

Describe the issue:

When user overscrolls, a layout exception is thrown

══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
The following assertion was thrown during performLayout():
SliverGeometry is not valid: The "scrollExtent" is negative.
The RenderSliver that returned the offending geometry was: _RenderSliverOverlapAbsorberX#c28e4 relayoutBoundary=up1 NEEDS-PAINT:
  needs compositing
  creator: CustomSliverOverlapAbsorber ← _ProfileSliverAppBar ← BlocListener<AuthWatcherCubit,
    AuthWatcherState> ← BlocSelector<AuthWatcherCubit, AuthWatcherState, User?> ←
    _NestedScrollViewViewport ← IgnorePointer-[GlobalKey#eb7c8] ← Semantics ← Listener ←
    _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#e565b] ←
    Listener ← _ScrollableScope ← ⋯
  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
  constraints: SliverConstraints(AxisDirection.down, GrowthDirection.forward, ScrollDirection.forward,
    scrollOffset: 0.0, remainingPaintExtent: 748.0, overlap: -148.0, crossAxisExtent: 414.0,
    crossAxisDirection: AxisDirection.right, viewportMainAxisExtent: 896.0, remainingCacheExtent:
    998.0, cacheOrigin: 0.0)
  geometry: SliverGeometry(scrollExtent: -0.0, paintExtent: 296.0, paintOrigin: -148.0, layoutExtent:
    148.0, maxPaintExtent: 296.0, hasVisualOverflow: true, cacheExtent: 148.0)
  handle: _SliverOverlapAbsorberHandle(0.0null)

The relevant error-causing widget was:
  CustomSliverOverlapAbsorber
  CustomSliverOverlapAbsorber:file:///Users/brendan/Mobile/FlutterProjects/sorosoke/lib/features/dashboard/presentation/screens/profile_sc
  reen.dart:125:12

When the exception was thrown, this was the stack:
#0      SliverGeometry.debugAssertIsValid.<anonymous closure>.verify (package:flutter/src/rendering/sliver.dart:712:9)
#1      SliverGeometry.debugAssertIsValid.<anonymous closure> (package:flutter/src/rendering/sliver.dart:721:7)
#2      SliverGeometry.debugAssertIsValid (package:flutter/src/rendering/sliver.dart:751:6)
#3      RenderSliver.debugAssertDoesMeetConstraints (package:flutter/src/rendering/sliver.dart:1205:22)
#4      RenderObject.layout.<anonymous closure> (package:flutter/src/rendering/object.dart:2138:9)
#5      RenderObject.layout (package:flutter/src/rendering/object.dart:2140:8)
#6      RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:516:13)
#7      RenderViewport._attemptLayout (package:flutter/src/rendering/viewport.dart:1600:12)
#8      RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:1507:20)
#9      RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1973:7)
#10     PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:999:18)
#11     RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:513:19)
#12     WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:884:13)
#13     RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:378:5)
#14     SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1175:15)
#15     SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1104:9)
#16     SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:1015:5)
#20     _invoke (dart:ui/hooks.dart:150:10)
#21     PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:318:5)
#22     _drawFrame (dart:ui/hooks.dart:115:31)
(elided 3 frames from dart:async)

The following RenderObject was being processed when the exception was fired: _RenderSliverOverlapAbsorberX#c28e4 relayoutBoundary=up1
NEEDS-PAINT:
  needs compositing
  creator: CustomSliverOverlapAbsorber ← _ProfileSliverAppBar ← BlocListener<AuthWatcherCubit,
    AuthWatcherState> ← BlocSelector<AuthWatcherCubit, AuthWatcherState, User?> ←
    _NestedScrollViewViewport ← IgnorePointer-[GlobalKey#eb7c8] ← Semantics ← Listener ←
    _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#e565b] ←
    Listener ← _ScrollableScope ← ⋯
  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
  constraints: SliverConstraints(AxisDirection.down, GrowthDirection.forward, ScrollDirection.forward,
    scrollOffset: 0.0, remainingPaintExtent: 746.7, overlap: -149.3, crossAxisExtent: 414.0,
    crossAxisDirection: AxisDirection.right, viewportMainAxisExtent: 896.0, remainingCacheExtent:
    996.7, cacheOrigin: 0.0)
  geometry: SliverGeometry(scrollExtent: -1.3, paintExtent: 297.3, paintOrigin: -149.3, layoutExtent:
    148.0, maxPaintExtent: 297.3, hasVisualOverflow: true, cacheExtent: 148.0)
  handle: _SliverOverlapAbsorberHandle(0.0null)
This RenderObject had the following descendants (showing up to depth 5):
    child: _RenderSliverPinnedPersistentHeaderForWidgets#10042 relayoutBoundary=up2 NEEDS-PAINT
      child: RenderSemanticsAnnotations#f31e0 relayoutBoundary=up3 NEEDS-PAINT
        child: RenderAnnotatedRegion<SystemUiOverlayStyle>#434e1 relayoutBoundary=up4 NEEDS-PAINT
          child: RenderPhysicalModel#bf5d5 relayoutBoundary=up5 NEEDS-PAINT
            child: _RenderInkFeatures#eba97 relayoutBoundary=up6 NEEDS-PAINT
════════════════════════════════════════════════════════════════════════════════════════════════════

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Another exception was thrown: SliverGeometry is not valid: The "scrollExtent" is negative.

Steps to Reproduce:

Use the default example in the Readme.md

• Change minHeight to 100
• Change maxHeight to 120
• Pull down the ScrollView past 120 (maxHeight)
• Platform - iOS

class Home extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: DefaultTabController(
        length: 2,
        child: CustomNestedScrollView(
          overscrollType: CustomOverscroll.outer,
          // !important
          physics: const BouncingScrollPhysics(
            parent: AlwaysScrollableScrollPhysics(),
          ),
          headerSliverBuilder: (context, innerScrolled) => <Widget>[
            MySliverAppBar(),
          ],
          body: TabBarView(
            children: [
              CustomScrollView(
                // !important
                physics: const BouncingScrollPhysics(
                  parent: AlwaysScrollableScrollPhysics(),
                ),
                slivers: <Widget>[
                  TopOverlapInjector(),
                  // scroll view
                  SliverFixedExtentList(
                    delegate: SliverChildBuilderDelegate(
                      (_, index) => ListTile(
                        key: Key('$index'),
                        title: Center(
                          child: Text('ListTile ${index + 1}'),
                        ),
                      ),
                      childCount: 30,
                    ),
                    itemExtent: 50,
                  ),
                ],
              ),
              CustomScrollView(
                physics: NeverScrollableScrollPhysics(),
                slivers: <Widget>[
                  TopOverlapInjector(),
                  // some widget
                  SliverFillRemaining(
                    child: Center(
                      child: Text('Test'),
                    ),
                  ),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class TopOverlapInjector extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Builder(
      builder: (context) => CustomSliverOverlapInjector(
        overscrollType: CustomOverscroll.outer,
        handle: CustomNestedScrollView.sliverOverlapAbsorberHandleFor(context),
      ),
    );
  }
}

class MySliverAppBar extends StatelessWidget {
  ///Header collapsed height
  final minHeight = 100.0;

  ///Header expanded height
  final maxHeight = 120.0;

  final tabBar = TabBar(
    tabs: <Widget>[Text('Tab1'), Text('Tab2')],
  );

  @override
  Widget build(BuildContext context) {
    final topHeight = MediaQuery.of(context).padding.top;
    return CustomSliverOverlapAbsorber(
      overscrollType: CustomOverscroll.outer,
      handle: CustomNestedScrollView.sliverOverlapAbsorberHandleFor(
        context,
      ),
      sliver: SliverAppBar(
        pinned: true,
        stretch: true,
        toolbarHeight: minHeight - tabBar.preferredSize.height - topHeight,
        collapsedHeight: minHeight - tabBar.preferredSize.height - topHeight,
        expandedHeight: maxHeight - topHeight,
        flexibleSpace: FlexibleSpaceBar(
          centerTitle: true,
          title: Center(child: Text('Example')),
          stretchModes: <StretchMode>[
            StretchMode.zoomBackground,
            StretchMode.blurBackground,
          ],
          background: Image.network(
            'https://pic1.zhimg.com/80/v2-fc35089cfe6c50f97324c98f963930c9_720w.jpg',
            fit: BoxFit.cover,
          ),
        ),
        bottom: tabBar,
      ),
    );
  }
}

There are some breaking changes in the API of flutter 3.4:

1. ScrollActivityDelegate has a new method updateBallisticAnimation which must be implemented
2. BallisticScrollActivity has a new parameter in its constructor: shouldIgnorePointer

Has someone already looked into this?

I'm using Flutter master branch, and I just pulled the lastest update and try starting my app, however I got an error from this plugin file.

My Flutter and Dart version info is below:

Flutter 3.7.0-13.0.pre.79 • channel master • https://github.com/flutter/flutter.git
Framework • revision 91c3f80c8c (15 hours ago) • 2022-12-27 04:44:24 -0500
Engine • revision 790604a09f
Tools • Dart 3.0.0 (build 3.0.0-64.0.dev) • DevTools 2.20.0

And in this version of Flutter, after I tried to start my app, I got this error (I tried flutter clean and pub get however the problem still there):

Launching lib\main.dart on sdk gphone64 x86 64 in debug mode...
lib\main.dart:1
: Error: The method '_NestedScrollMetrics.copyWith' doesn't have the named parameter 'devicePixelRatio' of overridden method 'Object with ScrollMetrics.copyWith'.
../…/src/nested_scroll_view.dart:526
  _NestedScrollMetrics copyWith({
                       ^
/C:/flutter/packages/flutter/lib/src/widgets/scroll_metrics.dart:43:17: Context: This is the overridden method ('copyWith').
  ScrollMetrics copyWith({
                ^

: Error: The superclass, 'FixedScrollMetrics', has no unnamed constructor that takes no arguments.
../…/src/nested_scroll_view.dart:514
  _NestedScrollMetrics({
  ^^^^^^^^^^^^^^^^^^^^
Target kernel_snapshot failed: Exception
2

FAILURE: Build failed with an exception.

* Where:
Script 'C:\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 1157

* What went wrong:
Execution failed for task ':app:compileFlutterBuildDebug'.
> Process 'command 'C:\flutter\bin\flutter.bat'' finished with non-zero exit value 1

* Try:
> Run with --stacktrace option to get the stack trace.
> Run with --info or --debug option to get more log output.
> Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 16s
Exception: Gradle task assembleDebug failed with exit code 1
Exited (sigterm)

: Warning: Operand of null-aware operation '!' has type 'SchedulerBinding' which excludes null.

• 'SchedulerBinding' is from 'package:flutter/src/scheduler/binding.dart' ('../../fvm/versions/3.0.0/packages/flutter/lib/src/scheduler/binding.dart'). SchedulerBinding.instance!.addPostFrameCallback( ^ Restarted application in 3,635ms. flutter: ^[[38;5;12m┌───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────<…> flutter: ^[[38;5;12m│ #0 AuthGuard.onNavigation (package:fullpass/routes/auth_guard.dart:15:14)<…> flutter: ^[[38;5;12m│ #1 StackRouter._canNavigate (package:auto_route/src/router/controller/routing_controller.dart:1093:13)<…> flutter: ^[[38;5;12m├┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄┄<…> flutter: ^[[38;5;12m│ 💡 AuthAuthorizedState()<…> flutter: ^[[38;5;12m└───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────<…>