Remove indicator from scrolling tab bars (#123057)

Remove indicator from scrolling tab bars

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

@@ -1441,13 +1441,17 @@ class _TabBarState extends State<TabBar> {
 
     if (widget.isScrollable) {
       _scrollController ??= _TabBarScrollController(this);
-      tabBar = SingleChildScrollView(
-        dragStartBehavior: widget.dragStartBehavior,
-        scrollDirection: Axis.horizontal,
-        controller: _scrollController,
-        padding: widget.padding,
-        physics: widget.physics,
-        child: tabBar,
+      tabBar = ScrollConfiguration(
+        // The scrolling tabs should not show an overscroll indicator.
+        behavior: ScrollConfiguration.of(context).copyWith(overscroll: false),
+        child: SingleChildScrollView(
+          dragStartBehavior: widget.dragStartBehavior,
+          scrollDirection: Axis.horizontal,
+          controller: _scrollController,
+          padding: widget.padding,
+          physics: widget.physics,
+          child: tabBar,
+        ),
       );
     } else if (widget.padding != null) {
       tabBar = Padding(

packages/flutter/test/material/tabs_test.dart

@@ -1351,6 +1351,13 @@ void main() {
     expect(controller.indexIsChanging, false);
   });
 
+  testWidgets('Scrollable TabBar does not have overscroll indicator', (WidgetTester tester) async {
+    final List<String> tabs = <String>['A', 'B', 'C'];
+
+    await tester.pumpWidget(buildFrame(tabs: tabs, value: 'A', isScrollable: true));
+    expect(find.byType(GlowingOverscrollIndicator), findsNothing);
+  });
+
   testWidgets('TabBar should not throw when animation is disabled in controller', (WidgetTester tester) async {
     // Regression test for https://github.com/flutter/flutter/issues/102600
     final List<String> tabs = <String>['A'];