feat: Change default value of keyboardDismissBehavior (#158580)

This PR aim to let developer choose the default
ScrollViewKeyboardDismissBehavior value.

I removed all default values of keyboardDismissBehavior and instead use
the one from `ScrollConfiguration`, which use as default value
`ScrollViewKeyboardDismissBehavior.manual`.

This PR try to fix : flutter/flutter#158566

<details/> 

<summary> Code Example </summary>

```dart
import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @OverRide
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      scrollBehavior: const MaterialScrollBehavior().copyWith(
        keyboardDismissBehavior: ScrollViewKeyboardDismissBehavior.onDrag,
      ),
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(),
    );
  }
}

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

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

class _MyHomePageState extends State<MyHomePage> {
  @OverRide
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: TextField(),
      ),
      body: ListView.builder(
        itemCount: 100,
        itemBuilder: (context, index) => ListTile(title: Text('Item $index')),
      ),
    );
  }
}
```

</details>


https://github.com/user-attachments/assets/8341c3da-2685-4f55-b8e9-11d2aae907db



## Pre-launch Checklist

- [X] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [X] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [X] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [X] I signed the [CLA].
- [X] I listed at least one issue that this PR fixes in the description
above.
- [X] I updated/added relevant documentation (doc comments with `///`).
- [X] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [X] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [X] All existing and new tests are passing.

<!-- Links -->
[Contributor Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview
[Tree Hygiene]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md
[test-exempt]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests
[Flutter Style Guide]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md
[Features we expect every widget to implement]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement
[CLA]: https://cla.developers.google.com/
[flutter/tests]: https://github.com/flutter/tests
[breaking change policy]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes
[Discord]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md
[Data Driven Fixes]:
https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md

---------

Co-authored-by: Kate Lovett <[email protected]>

Author: EArminjon

packages/flutter/lib/src/material/reorderable_list.dart

@@ -98,7 +98,7 @@ class ReorderableListView extends StatefulWidget {
     this.anchor = 0.0,
     this.cacheExtent,
     this.dragStartBehavior = DragStartBehavior.start,
-    this.keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual,
+    this.keyboardDismissBehavior,
     this.restorationId,
     this.clipBehavior = Clip.hardEdge,
     this.autoScrollerVelocityScalar,
@@ -169,7 +169,7 @@ class ReorderableListView extends StatefulWidget {
     this.anchor = 0.0,
     this.cacheExtent,
     this.dragStartBehavior = DragStartBehavior.start,
-    this.keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual,
+    this.keyboardDismissBehavior,
     this.restorationId,
     this.clipBehavior = Clip.hardEdge,
     this.autoScrollerVelocityScalar,
@@ -271,8 +271,9 @@ class ReorderableListView extends StatefulWidget {
 
   /// {@macro flutter.widgets.scroll_view.keyboardDismissBehavior}
   ///
-  /// The default is [ScrollViewKeyboardDismissBehavior.manual]
-  final ScrollViewKeyboardDismissBehavior keyboardDismissBehavior;
+  /// If [keyboardDismissBehavior] is null then it will fallback to the inherited
+  /// [ScrollBehavior.getKeyboardDismissBehavior].
+  final ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior;
 
   /// {@macro flutter.widgets.scrollable.restorationId}
   final String? restorationId;

packages/flutter/lib/src/widgets/reorderable_list.dart

@@ -168,7 +168,7 @@ class ReorderableList extends StatefulWidget {
     this.anchor = 0.0,
     this.cacheExtent,
     this.dragStartBehavior = DragStartBehavior.start,
-    this.keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual,
+    this.keyboardDismissBehavior,
     this.restorationId,
     this.clipBehavior = Clip.hardEdge,
     this.autoScrollerVelocityScalar,
@@ -280,8 +280,9 @@ class ReorderableList extends StatefulWidget {
 
   /// {@macro flutter.widgets.scroll_view.keyboardDismissBehavior}
   ///
-  /// The default is [ScrollViewKeyboardDismissBehavior.manual]
-  final ScrollViewKeyboardDismissBehavior keyboardDismissBehavior;
+  /// If [keyboardDismissBehavior] is null then it will fallback to the inherited
+  /// [ScrollBehavior.getKeyboardDismissBehavior].
+  final ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior;
 
   /// {@macro flutter.widgets.scrollable.restorationId}
   final String? restorationId;

packages/flutter/lib/src/widgets/scroll_configuration.dart

@@ -18,6 +18,7 @@ import 'package:flutter/services.dart' show LogicalKeyboardKey;
 import 'framework.dart';
 import 'overscroll_indicator.dart';
 import 'scroll_physics.dart';
+import 'scroll_view.dart';
 import 'scrollable.dart';
 import 'scrollable_helpers.dart';
 import 'scrollbar.dart';
@@ -89,6 +90,7 @@ class ScrollBehavior {
     Set<LogicalKeyboardKey>? pointerAxisModifiers,
     ScrollPhysics? physics,
     TargetPlatform? platform,
+    ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior,
   }) {
     return _WrappedScrollBehavior(
       delegate: this,
@@ -99,6 +101,7 @@ class ScrollBehavior {
       pointerAxisModifiers: pointerAxisModifiers,
       physics: physics,
       platform: platform,
+      keyboardDismissBehavior: keyboardDismissBehavior,
     );
   }
 
@@ -264,6 +267,12 @@ class ScrollBehavior {
   /// method returns false, the rebuilds might be optimized away.
   bool shouldNotify(covariant ScrollBehavior oldDelegate) => false;
 
+  /// The default keyboard dismissal behavior for [ScrollView] widgets.
+  ///
+  /// Defaults to [ScrollViewKeyboardDismissBehavior.manual].
+  ScrollViewKeyboardDismissBehavior getKeyboardDismissBehavior(BuildContext context) =>
+      ScrollViewKeyboardDismissBehavior.manual;
+
   @override
   String toString() => objectRuntimeType(this, 'ScrollBehavior');
 }
@@ -278,6 +287,7 @@ class _WrappedScrollBehavior implements ScrollBehavior {
     Set<LogicalKeyboardKey>? pointerAxisModifiers,
     this.physics,
     this.platform,
+    this.keyboardDismissBehavior,
   }) : _dragDevices = dragDevices,
        _pointerAxisModifiers = pointerAxisModifiers;
 
@@ -286,6 +296,7 @@ class _WrappedScrollBehavior implements ScrollBehavior {
   final bool overscroll;
   final ScrollPhysics? physics;
   final TargetPlatform? platform;
+  final ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior;
   final Set<PointerDeviceKind>? _dragDevices;
   final MultitouchDragStrategy? multitouchDragStrategy;
   final Set<LogicalKeyboardKey>? _pointerAxisModifiers;
@@ -327,6 +338,7 @@ class _WrappedScrollBehavior implements ScrollBehavior {
     Set<LogicalKeyboardKey>? pointerAxisModifiers,
     ScrollPhysics? physics,
     TargetPlatform? platform,
+    ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior,
   }) {
     return delegate.copyWith(
       scrollbars: scrollbars ?? this.scrollbars,
@@ -336,6 +348,7 @@ class _WrappedScrollBehavior implements ScrollBehavior {
       pointerAxisModifiers: pointerAxisModifiers ?? this.pointerAxisModifiers,
       physics: physics ?? this.physics,
       platform: platform ?? this.platform,
+      keyboardDismissBehavior: keyboardDismissBehavior ?? this.keyboardDismissBehavior,
     );
   }
 
@@ -349,6 +362,11 @@ class _WrappedScrollBehavior implements ScrollBehavior {
     return physics ?? delegate.getScrollPhysics(context);
   }
 
+  @override
+  ScrollViewKeyboardDismissBehavior getKeyboardDismissBehavior(BuildContext context) {
+    return keyboardDismissBehavior ?? delegate.getKeyboardDismissBehavior(context);
+  }
+
   @override
   bool shouldNotify(_WrappedScrollBehavior oldDelegate) {
     return oldDelegate.delegate.runtimeType != delegate.runtimeType ||

packages/flutter/lib/src/widgets/scroll_view.dart

@@ -118,7 +118,7 @@ abstract class ScrollView extends StatelessWidget {
     this.cacheExtent,
     this.semanticChildCount,
     this.dragStartBehavior = DragStartBehavior.start,
-    this.keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual,
+    this.keyboardDismissBehavior,
     this.restorationId,
     this.clipBehavior = Clip.hardEdge,
     this.hitTestBehavior = HitTestBehavior.opaque,
@@ -374,10 +374,14 @@ abstract class ScrollView extends StatelessWidget {
   final DragStartBehavior dragStartBehavior;
 
   /// {@template flutter.widgets.scroll_view.keyboardDismissBehavior}
-  /// [ScrollViewKeyboardDismissBehavior] the defines how this [ScrollView] will
+  /// The [ScrollViewKeyboardDismissBehavior] defines how this [ScrollView] will
   /// dismiss the keyboard automatically.
   /// {@endtemplate}
-  final ScrollViewKeyboardDismissBehavior keyboardDismissBehavior;
+  ///
+  /// If [keyboardDismissBehavior] is null then it will fallback to
+  /// [scrollBehavior]. If that is also null, the inherited
+  /// [ScrollBehavior.getKeyboardDismissBehavior] will be used.
+  final ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior;
 
   /// {@macro flutter.widgets.scrollable.restorationId}
   final String? restorationId;
@@ -505,7 +509,12 @@ abstract class ScrollView extends StatelessWidget {
             ? PrimaryScrollController.none(child: scrollable)
             : scrollable;
 
-    if (keyboardDismissBehavior == ScrollViewKeyboardDismissBehavior.onDrag) {
+    final ScrollViewKeyboardDismissBehavior effectiveKeyboardDismissBehavior =
+        keyboardDismissBehavior ??
+        scrollBehavior?.getKeyboardDismissBehavior(context) ??
+        ScrollConfiguration.of(context).getKeyboardDismissBehavior(context);
+
+    if (effectiveKeyboardDismissBehavior == ScrollViewKeyboardDismissBehavior.onDrag) {
       return NotificationListener<ScrollUpdateNotification>(
         child: scrollableResult,
         onNotification: (ScrollUpdateNotification notification) {

packages/flutter/lib/src/widgets/single_child_scroll_view.dart

@@ -18,6 +18,7 @@ import 'focus_scope.dart';
 import 'framework.dart';
 import 'notification_listener.dart';
 import 'primary_scroll_controller.dart';
+import 'scroll_configuration.dart';
 import 'scroll_controller.dart';
 import 'scroll_notification.dart';
 import 'scroll_physics.dart';
@@ -158,7 +159,7 @@ class SingleChildScrollView extends StatelessWidget {
     this.clipBehavior = Clip.hardEdge,
     this.hitTestBehavior = HitTestBehavior.opaque,
     this.restorationId,
-    this.keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual,
+    this.keyboardDismissBehavior,
   }) : assert(
          !(controller != null && (primary ?? false)),
          'Primary ScrollViews obtain their ScrollController via inheritance '
@@ -233,7 +234,10 @@ class SingleChildScrollView extends StatelessWidget {
   final String? restorationId;
 
   /// {@macro flutter.widgets.scroll_view.keyboardDismissBehavior}
-  final ScrollViewKeyboardDismissBehavior keyboardDismissBehavior;
+  ///
+  /// If [keyboardDismissBehavior] is null then it will fallback to the inherited
+  /// [ScrollBehavior.getKeyboardDismissBehavior].
+  final ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior;
 
   AxisDirection _getDirection(BuildContext context) {
     return getAxisDirectionFromAxisReverseAndDirectionality(context, scrollDirection, reverse);
@@ -271,7 +275,11 @@ class SingleChildScrollView extends StatelessWidget {
       },
     );
 
-    if (keyboardDismissBehavior == ScrollViewKeyboardDismissBehavior.onDrag) {
+    final ScrollViewKeyboardDismissBehavior effectiveKeyboardDismissBehavior =
+        keyboardDismissBehavior ??
+        ScrollConfiguration.of(context).getKeyboardDismissBehavior(context);
+
+    if (effectiveKeyboardDismissBehavior == ScrollViewKeyboardDismissBehavior.onDrag) {
       scrollable = NotificationListener<ScrollUpdateNotification>(
         child: scrollable,
         onNotification: (ScrollUpdateNotification notification) {

packages/flutter/lib/src/widgets/two_dimensional_scroll_view.dart

@@ -13,6 +13,7 @@ import 'focus_scope.dart';
 import 'framework.dart';
 import 'notification_listener.dart';
 import 'primary_scroll_controller.dart';
+import 'scroll_configuration.dart';
 import 'scroll_controller.dart';
 import 'scroll_delegate.dart';
 import 'scroll_notification.dart';
@@ -63,7 +64,7 @@ abstract class TwoDimensionalScrollView extends StatelessWidget {
     this.cacheExtent,
     this.diagonalDragBehavior = DiagonalDragBehavior.none,
     this.dragStartBehavior = DragStartBehavior.start,
-    this.keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual,
+    this.keyboardDismissBehavior,
     this.clipBehavior = Clip.hardEdge,
     this.hitTestBehavior = HitTestBehavior.opaque,
   });
@@ -109,7 +110,10 @@ abstract class TwoDimensionalScrollView extends StatelessWidget {
   final DragStartBehavior dragStartBehavior;
 
   /// {@macro flutter.widgets.scroll_view.keyboardDismissBehavior}
-  final ScrollViewKeyboardDismissBehavior keyboardDismissBehavior;
+  ///
+  /// If [keyboardDismissBehavior] is null then it will fallback to the inherited
+  /// [ScrollBehavior.getKeyboardDismissBehavior].
+  final ScrollViewKeyboardDismissBehavior? keyboardDismissBehavior;
 
   /// {@macro flutter.widgets.scrollable.hitTestBehavior}
   ///
@@ -187,7 +191,11 @@ abstract class TwoDimensionalScrollView extends StatelessWidget {
             ? PrimaryScrollController.none(child: scrollable)
             : scrollable;
 
-    if (keyboardDismissBehavior == ScrollViewKeyboardDismissBehavior.onDrag) {
+    final ScrollViewKeyboardDismissBehavior effectiveKeyboardDismissBehavior =
+        keyboardDismissBehavior ??
+        ScrollConfiguration.of(context).getKeyboardDismissBehavior(context);
+
+    if (effectiveKeyboardDismissBehavior == ScrollViewKeyboardDismissBehavior.onDrag) {
       return NotificationListener<ScrollUpdateNotification>(
         child: scrollableResult,
         onNotification: (ScrollUpdateNotification notification) {

packages/flutter/test/cupertino/app_test.dart

@@ -392,6 +392,51 @@ void main() {
     );
   });
 
+  testWidgets('CupertinoApp has correct default KeyboardDismissBehavior', (
+    WidgetTester tester,
+  ) async {
+    late BuildContext capturedContext;
+    await tester.pumpWidget(
+      CupertinoApp(
+        home: Builder(
+          builder: (BuildContext context) {
+            capturedContext = context;
+            return const Placeholder();
+          },
+        ),
+      ),
+    );
+
+    expect(
+      ScrollConfiguration.of(capturedContext).getKeyboardDismissBehavior(capturedContext),
+      ScrollViewKeyboardDismissBehavior.manual,
+    );
+  });
+
+  testWidgets('CupertinoApp can override default KeyboardDismissBehavior', (
+    WidgetTester tester,
+  ) async {
+    late BuildContext capturedContext;
+    await tester.pumpWidget(
+      CupertinoApp(
+        scrollBehavior: const CupertinoScrollBehavior().copyWith(
+          keyboardDismissBehavior: ScrollViewKeyboardDismissBehavior.onDrag,
+        ),
+        home: Builder(
+          builder: (BuildContext context) {
+            capturedContext = context;
+            return const Placeholder();
+          },
+        ),
+      ),
+    );
+
+    expect(
+      ScrollConfiguration.of(capturedContext).getKeyboardDismissBehavior(capturedContext),
+      ScrollViewKeyboardDismissBehavior.onDrag,
+    );
+  });
+
   testWidgets('A ScrollBehavior can be set for CupertinoApp', (WidgetTester tester) async {
     late BuildContext capturedContext;
     await tester.pumpWidget(

packages/flutter/test/material/app_test.dart

@@ -1248,6 +1248,51 @@ void main() {
     expect(ScrollConfiguration.of(capturedContext).runtimeType, MaterialScrollBehavior);
   });
 
+  testWidgets('MaterialApp has correct default KeyboardDismissBehavior', (
+    WidgetTester tester,
+  ) async {
+    late BuildContext capturedContext;
+    await tester.pumpWidget(
+      MaterialApp(
+        home: Builder(
+          builder: (BuildContext context) {
+            capturedContext = context;
+            return const Placeholder();
+          },
+        ),
+      ),
+    );
+
+    expect(
+      ScrollConfiguration.of(capturedContext).getKeyboardDismissBehavior(capturedContext),
+      ScrollViewKeyboardDismissBehavior.manual,
+    );
+  });
+
+  testWidgets('MaterialApp can override default KeyboardDismissBehavior', (
+    WidgetTester tester,
+  ) async {
+    late BuildContext capturedContext;
+    await tester.pumpWidget(
+      MaterialApp(
+        scrollBehavior: const MaterialScrollBehavior().copyWith(
+          keyboardDismissBehavior: ScrollViewKeyboardDismissBehavior.onDrag,
+        ),
+        home: Builder(
+          builder: (BuildContext context) {
+            capturedContext = context;
+            return const Placeholder();
+          },
+        ),
+      ),
+    );
+
+    expect(
+      ScrollConfiguration.of(capturedContext).getKeyboardDismissBehavior(capturedContext),
+      ScrollViewKeyboardDismissBehavior.onDrag,
+    );
+  });
+
   testWidgets('A ScrollBehavior can be set for MaterialApp', (WidgetTester tester) async {
     late BuildContext capturedContext;
     await tester.pumpWidget(