Add enableDrag property to CupertinoSheetRoute and showCupertinoSheet (#163923)

Implemented. (flutter#163852) This PR adds the `enableDrag` option to showCupertinoSheet and CupertinoSheetRoute, allowing developers to control whether the sheet can be dismissed by dragging. ## How to Verify - Set enableDrag: false in CupertinoSheetRoute or showCupertinoSheet. ```dart CupertinoSheetRoute<void>( builder: (BuildContext context) => const _SheetScaffold(), enableDrag: false, ), // or showCupertinoSheet<void>( context: context, useNestedNavigation: true, pageBuilder: (BuildContext context) => const _SheetScaffold(), enableDrag: false, ); ``` - The following is a screenshot of `examples/api/lib/cupertino/sheet/cupertino_sheet.0.dart` after adding `enableDrag: false`. https://github.com/user-attachments/assets/315fb0e5-ceee-4150-be6e-dd919a7c2317 ## 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]. - [ ] I followed the [breaking change policy] and added [Data Driven Fixes] where supported. - [x] All existing and new tests are passing. If you need help, consider asking for advice on the #hackers-new channel on [Discord].  [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: Tong Mu <dkwingsmt@users.noreply.github.com>
2025-03-26 06:15:48 +09:00
parent 0af426f37c
commit 71be3b14f9
2 changed files with 88 additions and 5 deletions
--- a/packages/flutter/lib/src/cupertino/sheet.dart
+++ b/packages/flutter/lib/src/cupertino/sheet.dart
@@ -104,6 +104,11 @@ final Animatable<double> _kScaleTween = Tween<double>(begin: 1.0, end: 1.0 - _kS
 /// The whole sheet can be popped at once by either dragging down on the sheet,
 /// or calling [CupertinoSheetRoute.popSheet].
 ///
+/// When `enableDrag` is set to `true` (the default), users can dismiss the sheet
+/// by dragging it down or by calling [CupertinoSheetRoute.popSheet]. When
+/// `enableDrag` is `false`, users cannot dismiss the sheet by dragging, and it
+/// can only be closed by calling [CupertinoSheetRoute.popSheet].
+///
 /// iOS sheet widgets are generally designed to be tightly coupled to the context
 /// of the widget that opened the sheet. As such, it is not recommended to push
 /// a non-sheet route that covers the sheet without first popping the sheet. If
@@ -135,6 +140,7 @@ Future<T?> showCupertinoSheet<T>({
  required BuildContext context,
  required WidgetBuilder pageBuilder,
  bool useNestedNavigation = false,
+  bool enableDrag = true,
 }) {
  final WidgetBuilder builder;
  final GlobalKey<NavigatorState> nestedNavigatorKey = GlobalKey<NavigatorState>();
@@ -175,7 +181,7 @@ Future<T?> showCupertinoSheet<T>({
  return Navigator.of(
    context,
    rootNavigator: true,
-  ).push<T>(CupertinoSheetRoute<T>(builder: builder));
+  ).push<T>(CupertinoSheetRoute<T>(builder: builder, enableDrag: enableDrag));
 }

 /// Provides an iOS-style sheet transition.
@@ -478,15 +484,17 @@ class _CupertinoSheetTransitionState extends State<CupertinoSheetTransition> {
 ///     `CupertinoSheetRoute`, with optional nested navigation built in.
 class CupertinoSheetRoute<T> extends PageRoute<T> with _CupertinoSheetRouteTransitionMixin<T> {
  /// Creates a page route that displays an iOS styled sheet.
-  CupertinoSheetRoute({super.settings, required this.builder});
+  CupertinoSheetRoute({super.settings, required this.builder, this.enableDrag = true});

  /// Builds the primary contents of the sheet route.
  final WidgetBuilder builder;

+  @override
+  final bool enableDrag;
+
  @override
  Widget buildContent(BuildContext context) {
    final double bottomPadding = MediaQuery.sizeOf(context).height * _kTopGapRatio;
-
    return MediaQuery.removePadding(
      context: context,
      removeTop: true,
@@ -563,6 +571,11 @@ mixin _CupertinoSheetRouteTransitionMixin<T> on PageRoute<T> {
  DelegatedTransitionBuilder? get delegatedTransition =>
      CupertinoSheetTransition.delegateTransition;

+  /// Determines whether the content can be dragged.
+  ///
+  /// If `true`, dragging is enabled; otherwise, it remains fixed.
+  bool get enableDrag;
+
  @override
  Widget buildPage(
    BuildContext context,
@@ -588,6 +601,7 @@ mixin _CupertinoSheetRouteTransitionMixin<T> on PageRoute<T> {
    Animation<double> animation,
    Animation<double> secondaryAnimation,
    Widget child,
+    bool enableDrag,
  ) {
    final bool linearTransition = route.popGestureInProgress;
    return CupertinoSheetTransition(
@@ -595,7 +609,7 @@ mixin _CupertinoSheetRouteTransitionMixin<T> on PageRoute<T> {
      secondaryRouteAnimation: secondaryAnimation,
      linearTransition: linearTransition,
      child: _CupertinoDownGestureDetector<T>(
-        enabledCallback: () => true,
+        enabledCallback: () => enableDrag,
        onStartPopGesture: () => _startPopGesture<T>(route),
        child: child,
      ),
@@ -614,7 +628,7 @@ mixin _CupertinoSheetRouteTransitionMixin<T> on PageRoute<T> {
    Animation<double> secondaryAnimation,
    Widget child,
  ) {
-    return buildPageTransitions<T>(this, context, animation, secondaryAnimation, child);
+    return buildPageTransitions<T>(this, context, animation, secondaryAnimation, child, enableDrag);
  }
 }

--- a/packages/flutter/test/cupertino/sheet_test.dart
+++ b/packages/flutter/test/cupertino/sheet_test.dart
@@ -1076,5 +1076,74 @@ void main() {
      await gesture.up();
      await tester.pumpAndSettle();
    });
+
+    testWidgets('dragging does not move the sheet when enableDrag is false', (
+      WidgetTester tester,
+    ) async {
+      Widget nonDragGestureApp(GlobalKey homeScaffoldKey, GlobalKey sheetScaffoldKey) {
+        return CupertinoApp(
+          home: CupertinoPageScaffold(
+            key: homeScaffoldKey,
+            child: Center(
+              child: Column(
+                children: <Widget>[
+                  const Text('Page 1'),
+                  CupertinoButton(
+                    onPressed: () {
+                      showCupertinoSheet<void>(
+                        context: homeScaffoldKey.currentContext!,
+                        pageBuilder: (BuildContext context) {
+                          return CupertinoPageScaffold(
+                            key: sheetScaffoldKey,
+                            child: const Center(child: Text('Page 2')),
+                          );
+                        },
+                        enableDrag: false,
+                      );
+                    },
+                    child: const Text('Push Page 2'),
+                  ),
+                ],
+              ),
+            ),
+          ),
+        );
+      }
+
+      final GlobalKey homeKey = GlobalKey();
+      final GlobalKey sheetKey = GlobalKey();
+
+      await tester.pumpWidget(nonDragGestureApp(homeKey, sheetKey));
+
+      await tester.tap(find.text('Push Page 2'));
+      await tester.pumpAndSettle();
+
+      expect(find.text('Page 2'), findsOneWidget);
+
+      RenderBox box = tester.renderObject(find.byKey(sheetKey)) as RenderBox;
+      final double initialPosition = box.localToGlobal(Offset.zero).dy;
+
+      final TestGesture gesture = await tester.startGesture(const Offset(100, 200));
+      // Partial drag down
+      await gesture.moveBy(const Offset(0, 200));
+      await tester.pump();
+
+      // Release gesture. Sheet should not move.
+      box = tester.renderObject(find.byKey(sheetKey)) as RenderBox;
+      final double middlePosition = box.localToGlobal(Offset.zero).dy;
+
+      expect(middlePosition, equals(initialPosition));
+
+      await gesture.up();
+      await tester.pumpAndSettle();
+
+      expect(find.text('Page 2'), findsOneWidget);
+
+      box = tester.renderObject(find.byKey(sheetKey)) as RenderBox;
+      final double finalPosition = box.localToGlobal(Offset.zero).dy;
+
+      expect(finalPosition, equals(middlePosition));
+      expect(finalPosition, equals(initialPosition));
+    });
  });
 }