Tapping a modal bottom sheet should not dismiss it by default (#32528)

Removed the GestureDetector from the modal bottom sheet that dismissed it on tap and updated several tests to accommodate this change.

examples/flutter_gallery/lib/demo/material/modal_bottom_sheet_demo.dart

@@ -24,7 +24,7 @@ class ModalBottomSheetDemo extends StatelessWidget {
               return Container(
                 child: Padding(
                   padding: const EdgeInsets.all(32.0),
-                  child: Text('This is the modal bottom sheet. Tap anywhere to dismiss.',
+                  child: Text('This is the modal bottom sheet. Slide down to dismiss.',
                     textAlign: TextAlign.center,
                     style: TextStyle(
                       color: Theme.of(context).accentColor,

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

@@ -281,43 +281,36 @@ class _ModalBottomSheetState<T> extends State<_ModalBottomSheet<T>> {
     final MaterialLocalizations localizations = MaterialLocalizations.of(context);
     final String routeLabel = _getRouteLabel(localizations);
 
-    return GestureDetector(
-      excludeFromSemantics: true,
-      onTap: () {
-        if (widget.route.isCurrent)
-          Navigator.pop(context);
-      },
-      child: AnimatedBuilder(
-        animation: widget.route.animation,
-        builder: (BuildContext context, Widget child) {
-          // Disable the initial animation when accessible navigation is on so
-          // that the semantics are added to the tree at the correct time.
-          final double animationValue = mediaQuery.accessibleNavigation ? 1.0 : widget.route.animation.value;
-          return Semantics(
-            scopesRoute: true,
-            namesRoute: true,
-            label: routeLabel,
-            explicitChildNodes: true,
-            child: ClipRect(
-              child: CustomSingleChildLayout(
-                delegate: _ModalBottomSheetLayout(animationValue, widget.isScrollControlled),
-                child: BottomSheet(
-                  animationController: widget.route._animationController,
-                  onClosing: () {
-                    if (widget.route.isCurrent) {
-                      Navigator.pop(context);
-                    }
-                  },
-                  builder: widget.route.builder,
-                  backgroundColor: widget.backgroundColor,
-                  elevation: widget.elevation,
-                  shape: widget.shape,
-                ),
+    return AnimatedBuilder(
+      animation: widget.route.animation,
+      builder: (BuildContext context, Widget child) {
+        // Disable the initial animation when accessible navigation is on so
+        // that the semantics are added to the tree at the correct time.
+        final double animationValue = mediaQuery.accessibleNavigation ? 1.0 : widget.route.animation.value;
+        return Semantics(
+          scopesRoute: true,
+          namesRoute: true,
+          label: routeLabel,
+          explicitChildNodes: true,
+          child: ClipRect(
+            child: CustomSingleChildLayout(
+              delegate: _ModalBottomSheetLayout(animationValue, widget.isScrollControlled),
+              child: BottomSheet(
+                animationController: widget.route._animationController,
+                onClosing: () {
+                  if (widget.route.isCurrent) {
+                    Navigator.pop(context);
+                  }
+                },
+                builder: widget.route.builder,
+                backgroundColor: widget.backgroundColor,
+                elevation: widget.elevation,
+                shape: widget.shape,
               ),
             ),
-          );
-        },
-      ),
+          ),
+        );
+      },
     );
   }
 }

packages/flutter/test/material/modal_bottom_sheet_test.dart → packages/flutter/test/material/bottom_sheet_test.dart

@@ -10,7 +10,7 @@ import 'package:flutter/gestures.dart';
 import '../widgets/semantics_tester.dart';
 
 void main() {
-  testWidgets('Verify that a tap dismisses a modal BottomSheet', (WidgetTester tester) async {
+  testWidgets('Tapping on a modal BottomSheet should not dismiss it', (WidgetTester tester) async {
     BuildContext savedContext;
 
     await tester.pumpWidget(MaterialApp(
@@ -33,28 +33,41 @@ void main() {
       showBottomSheetThenCalled = true;
     });
 
-    await tester.pump(); // bottom sheet show animation starts
-    await tester.pump(const Duration(seconds: 1)); // animation done
+    await tester.pumpAndSettle();
     expect(find.text('BottomSheet'), findsOneWidget);
     expect(showBottomSheetThenCalled, isFalse);
 
-    // Tap on the bottom sheet itself to dismiss it.
+    // Tap on the bottom sheet itself, it should not be dismissed
     await tester.tap(find.text('BottomSheet'));
-    await tester.pump(); // bottom sheet dismiss animation starts
-    expect(showBottomSheetThenCalled, isTrue);
-    await tester.pump(const Duration(seconds: 1)); // last frame of animation (sheet is entirely off-screen, but still present)
-    await tester.pump(const Duration(seconds: 1)); // frame after the animation (sheet has been removed)
+    await tester.pumpAndSettle();
+    expect(find.text('BottomSheet'), findsOneWidget);
+    expect(showBottomSheetThenCalled, isFalse);
+  });
+
+  testWidgets('Tapping outside a modal BottomSheet should dismiss it', (WidgetTester tester) async {
+    BuildContext savedContext;
+
+    await tester.pumpWidget(MaterialApp(
+      home: Builder(
+          builder: (BuildContext context) {
+            savedContext = context;
+            return Container();
+          }
+      ),
+    ));
+
+    await tester.pump();
     expect(find.text('BottomSheet'), findsNothing);
 
-    showBottomSheetThenCalled = false;
+    bool showBottomSheetThenCalled = false;
     showModalBottomSheet<void>(
       context: savedContext,
       builder: (BuildContext context) => const Text('BottomSheet'),
     ).then<void>((void value) {
       showBottomSheetThenCalled = true;
     });
-    await tester.pump(); // bottom sheet show animation starts
-    await tester.pump(const Duration(seconds: 1)); // animation done
+
+    await tester.pumpAndSettle();
     expect(find.text('BottomSheet'), findsOneWidget);
     expect(showBottomSheetThenCalled, isFalse);
 

packages/flutter/test/material/persistent_bottom_sheet_test.dart

@@ -406,8 +406,8 @@ void main() {
     await tester.pumpAndSettle();
     expect(find.text('modal bottom sheet'), findsOneWidget);
 
-    // Dismiss the modal bottomSheet
-    await tester.tap(find.text('modal bottom sheet'));
+    // Dismiss the modal bottomSheet by tapping above the sheet
+    await tester.tapAt(const Offset(20.0, 20.0));
     await tester.pumpAndSettle();
     expect(find.text('modal bottom sheet'), findsNothing);
     expect(find.text('showModalBottomSheet'), findsOneWidget);