Let apps report non-notification scroll deltas

CHANGELOG.md

@@ -8,6 +8,11 @@
   `Scaffold(resizeToAvoidBottomInset: false)`). No-op when insets are already
   zero, and does not affect `BottomBarScope.barHeight` or
   `BottomBarBodyPadding`.
+- `BottomBarController.reportScroll({required double delta})`: drives the
+  bar's threshold/reverse/`hideOnScroll` visibility rules from a scroll
+  source that never emits `ScrollNotification`s, such as an embedded WebView.
+  Visibility-only — it does not affect `scrollToStart()`/`scrollToEnd()`,
+  which still require a real `ScrollPosition`.
 
 ### Changed
 
@@ -28,6 +33,11 @@
   `borderRadius` to 28 so passing `layout:` no longer squares the bar.
   Pass `BorderRadius.zero` to opt out.
 
+### Fixed
+
+- Hidden bar descendants are excluded from keyboard focus, so a `TextField`
+  in the floating child cannot be tab-focused while the bar is hidden.
+
 ## 2.1.0
 
 ### Added

README.md

@@ -196,6 +196,21 @@ BottomBar(
 )
 ```
 
+### Non-notification scroll sources (e.g. WebView)
+
+`BottomBar` normally drives visibility from `ScrollNotification`s bubbled up
+from `body`. Some content — most notably an embedded WebView — scrolls
+internally without ever emitting one. For those cases, call
+`BottomBarController.reportScroll` from the WebView's own scroll callback:
+
+```dart
+controller.reportScroll(delta: newPixels - oldPixels);
+```
+
+This drives the same threshold/reverse/`hideOnScroll` visibility rules as
+body scrolling. It only affects visibility — `scrollToStart()`/`scrollToEnd()`
+still require a real `ScrollPosition`, which a WebView cannot provide.
+
 ### Custom transitions
 
 Custom transition builders must preserve the child's layout footprint. Use
@@ -339,6 +354,7 @@ animating.
 | `show()` / `hide()` / `toggle()` | Imperative visibility controls. |
 | `scrollToStart()` | Always scrolls the last active scrollable to its minimum extent. |
 | `scrollToEnd()` | Always scrolls the last active scrollable to its maximum extent. |
+| `reportScroll(delta: ...)` | Drives visibility from a source that doesn't emit `ScrollNotification`s (e.g. WebView). Visibility only; doesn't affect `scrollToStart`/`scrollToEnd`. |
 
 A controller can own only one live bar at a time. Double-attach fails in both
 debug and release, and visibility updates are accepted only from the owning bar

example/pubspec.lock

@@ -42,7 +42,7 @@ packages:
     source: hosted
     version: "1.19.1"
   cupertino_ui:
-    dependency: transitive
+    dependency: "direct main"
     description:
       name: cupertino_ui
       sha256: e9dfe7fac704028f8928cbe4028a0be5e8a709498e8daf8247de99e99a32aef3
@@ -99,10 +99,10 @@ packages:
     dependency: transitive
     description:
       name: intl
-      sha256: "1ca20c894b1717686a2319b8548763d812bc0aabdac580420a44c5178c57a867"
+      sha256: "3df61194eb431efc39c4ceba583b95633a403f46c9fd341e550ce0bfa50e9aa5"
       url: "https://pub.dev"
     source: hosted
-    version: "0.20.3"
+    version: "0.20.2"
   leak_tracker:
     dependency: transitive
     description:
@@ -139,10 +139,10 @@ packages:
     dependency: transitive
     description:
       name: matcher
-      sha256: "31bd099b47c10cd1aeb55146a2d46ce0277630ecef3f7dae54ad7873f36696cd"
+      sha256: dc0b7dc7651697ea4ff3e69ef44b0407ea32c487a39fff6a4004fa585e901861
       url: "https://pub.dev"
     source: hosted
-    version: "0.12.20"
+    version: "0.12.19"
   material_color_utilities:
     dependency: transitive
     description:
@@ -163,10 +163,10 @@ packages:
     dependency: transitive
     description:
       name: meta
-      sha256: "307249ce4ff29d58a18e97f6345f539382eb9c9c29ecda628900f31de0443dd9"
+      sha256: "1741988757a65eb6b36abe716829688cf01910bbf91c34354ff7ec1c3de2b349"
       url: "https://pub.dev"
     source: hosted
-    version: "1.19.0"
+    version: "1.18.0"
   motor:
     dependency: transitive
     description:
@@ -232,18 +232,18 @@ packages:
     dependency: transitive
     description:
       name: test_api
-      sha256: "2a122cbe059f8b610d3a5415f42e255b6c17b1f21eee1d960f31080237fb4f11"
+      sha256: "949a932224383300f01be9221c39180316445ecb8e7547f70a41a35bf421fb9e"
       url: "https://pub.dev"
     source: hosted
-    version: "0.7.12"
+    version: "0.7.11"
   vector_math:
     dependency: transitive
     description:
       name: vector_math
-      sha256: f36f9f3be64c6198714492bb455c11056e33e2f85d9a0b676a48301e44fdcf47
+      sha256: d530bd74fea330e6e364cda7a85019c434070188383e1cd8d9777ee586914c5b
       url: "https://pub.dev"
     source: hosted
-    version: "2.4.2"
+    version: "2.2.0"
   vm_service:
     dependency: transitive
     description:

example/pubspec.yaml

@@ -13,7 +13,10 @@ dependencies:
   flutter_floating_bottom_bar:
     path: ../
 
-  material_ui: ^1.0.0
+  # Upper bounds mirror the parent package: material_ui 1.3.0 and
+  # cupertino_ui 1.1.0 need a newer Dart than Flutter 3.44.4 ships.
+  material_ui: ">=1.0.0 <1.3.0"
+  cupertino_ui: ">=1.0.0 <1.1.0"
 
 dev_dependencies:
   flutter_test:

lib/src/bottom_bar.dart

@@ -351,6 +351,12 @@ class _BottomBarState extends State<BottomBar>
     _setBarVisible(true, notifyCallbacks: true, fromController: true);
   }
 
+  @override
+  void reportScroll({required double delta}) {
+    if (!mounted) return;
+    _dispatcher.handleDelta(delta);
+  }
+
   /// Returns the [NestedScrollViewState] enclosing [context], or `null` if the
   /// active scrollable is not inside a [NestedScrollView] (or the context is no
   /// longer mounted).

lib/src/bottom_bar_controller.dart

@@ -38,8 +38,8 @@ class BottomBarController extends ChangeNotifier {
 
   /// Whether this controller is currently attached to a live [BottomBar].
   ///
-  /// [show], [hide], [toggle], [scrollToStart], and [scrollToEnd] are no-ops
-  /// when [isAttached] is `false`.
+  /// [show], [hide], [toggle], [reportScroll], [scrollToStart], and
+  /// [scrollToEnd] are no-ops when [isAttached] is `false`.
   bool get isAttached => _binding != null;
 
   /// Shows the bar, animating it into view if it is currently hidden.
@@ -61,6 +61,24 @@ class BottomBarController extends ChangeNotifier {
     }
   }
 
+  /// Reports a scroll delta from a source that does not emit
+  /// [ScrollNotification]s, such as an embedded WebView.
+  ///
+  /// [delta] is signed: positive moves toward the end (the usual "hide"
+  /// direction), negative moves toward the start (the usual "show"
+  /// direction) — for example `newPixels - oldPixels` from the WebView's own
+  /// scroll callback. Drives the same threshold/reverse/
+  /// [BottomBarScrollBehavior.hideOnScroll] visibility rules as body
+  /// [ScrollNotification]s.
+  ///
+  /// This only affects visibility. It never affects [scrollToStart] or
+  /// [scrollToEnd], which require a real [ScrollPosition] to have been
+  /// observed via a [ScrollNotification] first.
+  ///
+  /// No-op if the controller is not attached.
+  void reportScroll({required double delta}) =>
+      _binding?.reportScroll(delta: delta);
+
   /// Animates the most-recently-active scrollable inside [BottomBar.body] to
   /// its [ScrollPosition.minScrollExtent] (i.e. the start/top boundary).
   ///
@@ -130,4 +148,5 @@ abstract class BottomBarBindingForController {
   bool get isVisible;
   void requestVisible(bool visible);
   Future<void> scrollToBoundary({required bool toEnd});
+  void reportScroll({required double delta});
 }

lib/src/internal/scroll_notification_dispatcher.dart

@@ -31,6 +31,8 @@ class ScrollNotificationDispatcher {
   final LinkedHashMap<int, _TrackedScrollState> _trackedScrollables =
       LinkedHashMap<int, _TrackedScrollState>();
 
+  _TrackedScrollState? _externalState;
+
   ScrollPosition? _lastActivePosition;
   ScrollPosition? get lastActivePosition => _lastActivePosition;
 
@@ -104,6 +106,29 @@ class ScrollNotificationDispatcher {
       return;
     }
 
+    _handlePixels(state, pixels);
+  }
+
+  /// Reports a scroll delta from a source that never emits
+  /// [ScrollNotification]s (e.g. an embedded WebView).
+  ///
+  /// [delta] is signed: positive moves toward the end (the usual hide
+  /// direction), negative moves toward the start (the usual show direction).
+  /// Applies the same [deltaThreshold]/[reverse] accumulation as [handle],
+  /// but tracks its own independent accumulator: it never runs [predicate],
+  /// never touches [lastActivePosition]/[lastActiveContext], and does not
+  /// share state with notification-tracked scrollables.
+  void handleDelta(double delta) {
+    if (delta == 0) return;
+
+    final state = _externalState ??= _TrackedScrollState(
+      anchorPixels: 0,
+      lastPixels: 0,
+    );
+    _handlePixels(state, state.lastPixels + delta);
+  }
+
+  void _handlePixels(_TrackedScrollState state, double pixels) {
     final delta = pixels - state.lastPixels;
     state.lastPixels = pixels;
     if (delta == 0) return;

lib/src/internal/visibility_animator.dart

@@ -69,9 +69,12 @@ class VisibilityAnimator extends StatelessWidget {
   }
 
   Widget _wrapInteraction(Widget child) {
-    return IgnorePointer(
-      ignoring: !isVisible,
-      child: ExcludeSemantics(excluding: !isVisible, child: child),
+    return ExcludeFocus(
+      excluding: !isVisible,
+      child: IgnorePointer(
+        ignoring: !isVisible,
+        child: ExcludeSemantics(excluding: !isVisible, child: child),
+      ),
     );
   }
 }

pubspec.yaml

@@ -11,7 +11,11 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
-  material_ui: ^1.0.0
+  # Upper bounds are pinned because material_ui 1.3.0 and cupertino_ui 1.1.0
+  # use @awaitNotRequired, which the Dart shipped with Flutter 3.44.4
+  # cannot compile. Revert to open ranges after bumping past Flutter 3.44.
+  material_ui: ">=1.0.0 <1.3.0"
+  cupertino_ui: ">=1.0.0 <1.1.0"
   motor: ^1.1.0
 
 dev_dependencies:

test/bottom_bar_controller_test.dart

@@ -38,6 +38,10 @@ void main() {
       await controller.scrollToEnd();
       expect(first.lastScrollToEnd, isTrue);
       expect(second.lastScrollToEnd, isNull);
+
+      controller.reportScroll(delta: 42);
+      expect(first.lastReportedDelta, 42);
+      expect(second.lastReportedDelta, isNull);
     },
   );
 
@@ -103,6 +107,7 @@ class _FakeBinding implements BottomBarBindingForController {
 
   bool? requestedVisibility;
   bool? lastScrollToEnd;
+  double? lastReportedDelta;
 
   @override
   void requestVisible(bool visible) {
@@ -113,4 +118,9 @@ class _FakeBinding implements BottomBarBindingForController {
   Future<void> scrollToBoundary({required bool toEnd}) async {
     lastScrollToEnd = toEnd;
   }
+
+  @override
+  void reportScroll({required double delta}) {
+    lastReportedDelta = delta;
+  }
 }

test/floating_bar_test.dart

@@ -152,6 +152,58 @@ void main() {
     expect(controller.isVisible, isFalse);
   });
 
+  testWidgets('reportScroll hides the bar like a body scroll would', (
+    tester,
+  ) async {
+    final controller = BottomBarController();
+    await tester.pumpWidget(buildHarness(controller: controller));
+    expect(controller.isVisible, isTrue);
+
+    controller.reportScroll(delta: 80);
+    await tester.pumpAndSettle();
+
+    expect(controller.isVisible, isFalse);
+  });
+
+  testWidgets('reportScroll shows the bar again on a negative delta', (
+    tester,
+  ) async {
+    final controller = BottomBarController();
+    await tester.pumpWidget(buildHarness(controller: controller));
+
+    controller.reportScroll(delta: 80);
+    await tester.pumpAndSettle();
+    expect(controller.isVisible, isFalse);
+
+    controller.reportScroll(delta: -80);
+    await tester.pumpAndSettle();
+
+    expect(controller.isVisible, isTrue);
+  });
+
+  testWidgets('reportScroll respects hideOnScroll: false', (tester) async {
+    final controller = BottomBarController();
+    await tester.pumpWidget(
+      buildHarness(
+        controller: controller,
+        scrollBehavior: const BottomBarScrollBehavior(hideOnScroll: false),
+      ),
+    );
+
+    controller.reportScroll(delta: 80);
+    await tester.pumpAndSettle();
+
+    expect(controller.isVisible, isTrue);
+  });
+
+  testWidgets('reportScroll on an unattached controller does not throw', (
+    tester,
+  ) async {
+    final controller = BottomBarController();
+
+    expect(() => controller.reportScroll(delta: 80), returnsNormally);
+  });
+
   testWidgets('showAtStart forces the bar visible at the top boundary', (
     tester,
   ) async {

test/hidden_focus_test.dart

@@ -0,0 +1,47 @@
+import 'package:material_ui/material_ui.dart';
+import 'package:flutter_floating_bottom_bar/flutter_floating_bottom_bar.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('hiding the bar removes focus from its descendants', (
+    tester,
+  ) async {
+    final controller = BottomBarController();
+    final focusNode = FocusNode();
+    addTearDown(() {
+      focusNode.dispose();
+      controller.dispose();
+    });
+
+    await tester.pumpWidget(
+      MaterialApp(
+        home: Scaffold(
+          body: BottomBar(
+            controller: controller,
+            body: const SizedBox.shrink(),
+            child: TextField(focusNode: focusNode),
+          ),
+        ),
+      ),
+    );
+
+    focusNode.requestFocus();
+    await tester.pump();
+    expect(focusNode.hasFocus, isTrue);
+
+    controller.hide();
+    await tester.pumpAndSettle();
+
+    expect(focusNode.hasFocus, isFalse);
+
+    focusNode.requestFocus();
+    await tester.pump();
+    expect(focusNode.hasFocus, isFalse);
+
+    controller.show();
+    await tester.pumpAndSettle();
+    focusNode.requestFocus();
+    await tester.pump();
+    expect(focusNode.hasFocus, isTrue);
+  });
+}