commit 2130cf9c02375b270e3a14d337edafc9b6336173
author Kate Lovett <katelovett@google.com> Wed Jun 23 15:36:03 2021 -0500
committer GitHub <noreply@github.com> Wed Jun 23 13:36:03 2021 -0700
tree e33c8a1c45dd92eb55f42b62d63a2f463259b607
parent 9c0bd18c40f1509e16079142c441bfee025da976

DismissDirection.none will not prevent scrolling (#85152)

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

diff --git a/packages/flutter/lib/src/widgets/dismissible.dart b/packages/flutter/lib/src/widgets/dismissible.dart
index 9d7108f..290c5d9 100644
--- a/packages/flutter/lib/src/widgets/dismissible.dart
+++ b/packages/flutter/lib/src/widgets/dismissible.dart
@@ -610,6 +610,12 @@
         content,
       ]);
     }
+
+    // If the DismissDirection is none, we do not add drag gestures because the content
+    // cannot be dragged.
+    if (widget.direction == DismissDirection.none)
+      return content;
+
     // We are not resizing but we may be being dragging in widget.direction.
     return GestureDetector(
       onHorizontalDragStart: _directionIsXAxis ? _handleDragStart : null,

packages/flutter/test/widgets/dismissible_test.dart

diff --git a/packages/flutter/test/widgets/dismissible_test.dart b/packages/flutter/test/widgets/dismissible_test.dart
index ced2e78..e8b5582 100644
--- a/packages/flutter/test/widgets/dismissible_test.dart
+++ b/packages/flutter/test/widgets/dismissible_test.dart
@@ -18,6 +18,7 @@
   double? startToEndThreshold,
   TextDirection textDirection = TextDirection.ltr,
   Future<bool?> Function(BuildContext context, DismissDirection direction)? confirmDismiss,
+  ScrollController? controller,
 }) {
   return Directionality(
     textDirection: textDirection,
@@ -57,10 +58,11 @@
         return Container(
           padding: const EdgeInsets.all(10.0),
           child: ListView(
+            controller: controller,
             dragStartBehavior: DragStartBehavior.down,
             scrollDirection: scrollDirection,
             itemExtent: itemExtent,
-            children: <int>[0, 1, 2, 3, 4]
+            children: <int>[0, 1, 2, 3, 4, 5, 6, 7, 8]
               .where((int i) => !dismissedItems.contains(i))
               .map<Widget>(buildDismissibleItem).toList(),
           ),
@@ -873,4 +875,22 @@
     await dismissItem(tester, 0, gestureDirection: AxisDirection.down);
     expect(find.text('0'), findsOneWidget);
   });
+
+  testWidgets('DismissDirection.none does not prevent scrolling', (WidgetTester tester) async {
+    dismissDirection = DismissDirection.none;
+    final ScrollController controller = ScrollController();
+
+    await tester.pumpWidget(buildTest(controller: controller));
+    expect(dismissedItems, isEmpty);
+    expect(controller.offset, 0.0);
+
+    await dismissItem(tester, 0, gestureDirection: AxisDirection.left);
+    expect(controller.offset, 0.0);
+    await dismissItem(tester, 0, gestureDirection: AxisDirection.right);
+    expect(controller.offset, 0.0);
+    await dismissItem(tester, 0, gestureDirection: AxisDirection.down);
+    expect(controller.offset, 0.0);
+    await dismissItem(tester, 0, gestureDirection: AxisDirection.up);
+    expect(controller.offset, 99.9);
+  });
 }