Revert "Fix Material 3 Scrollable `TabBar`" (#129383)

Reverts flutter/flutter#125974

dev/tools/gen_defaults/generated/used_tokens.csv

@@ -529,7 +529,6 @@ md.comp.primary-navigation-tab.active.hover.state-layer.opacity,
 md.comp.primary-navigation-tab.active.pressed.state-layer.color,
 md.comp.primary-navigation-tab.active.pressed.state-layer.opacity,
 md.comp.primary-navigation-tab.divider.color,
-md.comp.primary-navigation-tab.divider.height,
 md.comp.primary-navigation-tab.inactive.focus.state-layer.color,
 md.comp.primary-navigation-tab.inactive.focus.state-layer.opacity,
 md.comp.primary-navigation-tab.inactive.hover.state-layer.color,
@@ -589,7 +588,6 @@ md.comp.search-view.header.supporting-text.color,
 md.comp.search-view.header.supporting-text.text-style,
 md.comp.secondary-navigation-tab.active.label-text.color,
 md.comp.secondary-navigation-tab.divider.color,
-md.comp.secondary-navigation-tab.divider.height,
 md.comp.secondary-navigation-tab.focus.state-layer.color,
 md.comp.secondary-navigation-tab.focus.state-layer.opacity,
 md.comp.secondary-navigation-tab.hover.state-layer.color,

dev/tools/gen_defaults/lib/tabs_template.dart

@@ -24,9 +24,6 @@ class _${blockName}PrimaryDefaultsM3 extends TabBarTheme {
   @override
   Color? get dividerColor => ${componentColor("md.comp.primary-navigation-tab.divider")};
 
-  @override
-  double? get dividerHeight => ${getToken('md.comp.primary-navigation-tab.divider.height')};
-
   @override
   Color? get indicatorColor => ${componentColor("md.comp.primary-navigation-tab.active-indicator")};
 
@@ -74,7 +71,7 @@ class _${blockName}PrimaryDefaultsM3 extends TabBarTheme {
   InteractiveInkFeatureFactory? get splashFactory => Theme.of(context).splashFactory;
 
   @override
-  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.startOffset : TabAlignment.fill;
+  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.start : TabAlignment.fill;
 
   static double indicatorWeight = ${getToken('md.comp.primary-navigation-tab.active-indicator.height')};
 }
@@ -91,9 +88,6 @@ class _${blockName}SecondaryDefaultsM3 extends TabBarTheme {
   @override
   Color? get dividerColor => ${componentColor("md.comp.secondary-navigation-tab.divider")};
 
-  @override
-  double? get dividerHeight => ${getToken('md.comp.secondary-navigation-tab.divider.height')};
-
   @override
   Color? get indicatorColor => ${componentColor("md.comp.primary-navigation-tab.active-indicator")};
 
@@ -141,7 +135,7 @@ class _${blockName}SecondaryDefaultsM3 extends TabBarTheme {
   InteractiveInkFeatureFactory? get splashFactory => Theme.of(context).splashFactory;
 
   @override
-  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.startOffset : TabAlignment.fill;
+  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.start : TabAlignment.fill;
 }
 ''';
 

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

@@ -32,7 +32,6 @@ class TabBarTheme with Diagnosticable {
     this.indicatorColor,
     this.indicatorSize,
     this.dividerColor,
-    this.dividerHeight,
     this.labelColor,
     this.labelPadding,
     this.labelStyle,
@@ -56,9 +55,6 @@ class TabBarTheme with Diagnosticable {
   /// Overrides the default value for [TabBar.dividerColor].
   final Color? dividerColor;
 
-  /// Overrides the default value for [TabBar.dividerHeight].
-  final double? dividerHeight;
-
   /// Overrides the default value for [TabBar.labelColor].
   ///
   /// If [labelColor] is a [MaterialStateColor], then the effective color will
@@ -105,7 +101,6 @@ class TabBarTheme with Diagnosticable {
     Color? indicatorColor,
     TabBarIndicatorSize? indicatorSize,
     Color? dividerColor,
-    double? dividerHeight,
     Color? labelColor,
     EdgeInsetsGeometry? labelPadding,
     TextStyle? labelStyle,
@@ -121,7 +116,6 @@ class TabBarTheme with Diagnosticable {
       indicatorColor: indicatorColor ?? this.indicatorColor,
       indicatorSize: indicatorSize ?? this.indicatorSize,
       dividerColor: dividerColor ?? this.dividerColor,
-      dividerHeight: dividerHeight ?? this.dividerHeight,
       labelColor: labelColor ?? this.labelColor,
       labelPadding: labelPadding ?? this.labelPadding,
       labelStyle: labelStyle ?? this.labelStyle,
@@ -153,7 +147,6 @@ class TabBarTheme with Diagnosticable {
       indicatorColor: Color.lerp(a.indicatorColor, b.indicatorColor, t),
       indicatorSize: t < 0.5 ? a.indicatorSize : b.indicatorSize,
       dividerColor: Color.lerp(a.dividerColor, b.dividerColor, t),
-      dividerHeight: t < 0.5 ? a.dividerHeight : b.dividerHeight,
       labelColor: Color.lerp(a.labelColor, b.labelColor, t),
       labelPadding: EdgeInsetsGeometry.lerp(a.labelPadding, b.labelPadding, t),
       labelStyle: TextStyle.lerp(a.labelStyle, b.labelStyle, t),
@@ -172,7 +165,6 @@ class TabBarTheme with Diagnosticable {
     indicatorColor,
     indicatorSize,
     dividerColor,
-    dividerHeight,
     labelColor,
     labelPadding,
     labelStyle,
@@ -197,7 +189,6 @@ class TabBarTheme with Diagnosticable {
         && other.indicatorColor == indicatorColor
         && other.indicatorSize == indicatorSize
         && other.dividerColor == dividerColor
-        && other.dividerHeight == dividerHeight
         && other.labelColor == labelColor
         && other.labelPadding == labelPadding
         && other.labelStyle == labelStyle

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

@@ -397,8 +397,6 @@ class _IndicatorPainter extends CustomPainter {
     required this.indicatorPadding,
     required this.labelPaddings,
     this.dividerColor,
-    this.dividerHeight,
-    required this.width,
   }) : super(repaint: controller.animation) {
     if (old != null) {
       saveTabOffsets(old._currentTabOffsets, old._currentTextDirection);
@@ -410,10 +408,8 @@ class _IndicatorPainter extends CustomPainter {
   final TabBarIndicatorSize? indicatorSize;
   final EdgeInsetsGeometry indicatorPadding;
   final List<GlobalKey> tabKeys;
-  final List<EdgeInsetsGeometry> labelPaddings;
   final Color? dividerColor;
-  final double? dividerHeight;
-  final double width;
+  final List<EdgeInsetsGeometry> labelPaddings;
 
   // _currentTabOffsets and _currentTextDirection are set each time TabBar
   // layout is completed. These values can be null when TabBar contains no
@@ -506,10 +502,8 @@ class _IndicatorPainter extends CustomPainter {
       textDirection: _currentTextDirection,
     );
     if (dividerColor != null) {
-      final Paint dividerPaint = Paint()..color = dividerColor!..strokeWidth = dividerHeight!;
-      final Offset dividerP1 = Offset(-width, size.height - (dividerPaint.strokeWidth / 2));
-      final Offset dividerP2 = Offset(width, size.height - (dividerPaint.strokeWidth / 2));
-      canvas.drawLine(dividerP1, dividerP2, dividerPaint);
+      final Paint dividerPaint = Paint()..color = dividerColor!..strokeWidth = 1;
+      canvas.drawLine(Offset(0, size.height), Offset(size.width, size.height), dividerPaint);
     }
     _painter!.paint(canvas, _currentRect!.topLeft, configuration);
   }
@@ -724,7 +718,6 @@ class TabBar extends StatefulWidget implements PreferredSizeWidget {
     this.indicator,
     this.indicatorSize,
     this.dividerColor,
-    this.dividerHeight,
     this.labelColor,
     this.labelStyle,
     this.labelPadding,
@@ -775,7 +768,6 @@ class TabBar extends StatefulWidget implements PreferredSizeWidget {
     this.indicator,
     this.indicatorSize,
     this.dividerColor,
-    this.dividerHeight,
     this.labelColor,
     this.labelStyle,
     this.labelPadding,
@@ -903,13 +895,6 @@ class TabBar extends StatefulWidget implements PreferredSizeWidget {
   /// [ColorScheme.surfaceVariant] will be used, otherwise divider will not be drawn.
   final Color? dividerColor;
 
-  /// The height of the divider.
-  ///
-  /// If null and [ThemeData.useMaterial3] is true, [TabBarTheme.dividerHeight] is used.
-  /// If that is also null and [ThemeData.useMaterial3] is true, 1.0 will be used.
-  /// Otherwise divider will not be drawn.
-  final double? dividerHeight;
-
   /// The color of selected tab labels.
   ///
   /// If null, then [TabBarTheme.labelColor] is used. If that is also null and
@@ -1169,8 +1154,8 @@ class _TabBarState extends State<TabBar> {
   TabBarTheme get _defaults {
     if (Theme.of(context).useMaterial3) {
       return widget._isPrimary
-        ? _TabsPrimaryDefaultsM3(context, widget.isScrollable)
-        : _TabsSecondaryDefaultsM3(context, widget.isScrollable);
+          ? _TabsPrimaryDefaultsM3(context, widget.isScrollable)
+          : _TabsSecondaryDefaultsM3(context, widget.isScrollable);
     } else {
       return _TabsDefaultsM2(context, widget.isScrollable);
     }
@@ -1284,10 +1269,8 @@ class _TabBarState extends State<TabBar> {
       indicatorPadding: widget.indicatorPadding,
       tabKeys: _tabKeys,
       old: _indicatorPainter,
-      labelPaddings: _labelPaddings,
       dividerColor: theme.useMaterial3 ? widget.dividerColor ?? tabBarTheme.dividerColor ?? _defaults.dividerColor : null,
-      dividerHeight: theme.useMaterial3 ? widget.dividerHeight ?? tabBarTheme.dividerHeight ?? _defaults.dividerHeight : null,
-      width: MediaQuery.sizeOf(context).width,
+      labelPaddings: _labelPaddings,
     );
   }
 
@@ -1492,7 +1475,6 @@ class _TabBarState extends State<TabBar> {
   Widget build(BuildContext context) {
     assert(debugCheckHasMaterialLocalizations(context));
     assert(_debugScheduleCheckHasValidTabsCount());
-    final ThemeData theme = Theme.of(context);
     final TabBarTheme tabBarTheme = TabBarTheme.of(context);
     final TabAlignment effectiveTabAlignment = widget.tabAlignment ?? tabBarTheme.tabAlignment ?? _defaults.tabAlignment!;
     assert(_debugTabAlignmentIsValid(effectiveTabAlignment));
@@ -1645,17 +1627,6 @@ class _TabBarState extends State<TabBar> {
           child: tabBar,
         ),
       );
-      if (theme.useMaterial3) {
-        final AlignmentGeometry effectiveAlignment = switch (effectiveTabAlignment) {
-          TabAlignment.center => Alignment.center,
-          TabAlignment.start || TabAlignment.startOffset || TabAlignment.fill => AlignmentDirectional.centerStart,
-        };
-        tabBar = Align(
-          heightFactor: 1.0,
-          alignment: effectiveAlignment,
-          child: tabBar,
-        );
-      }
     } else if (widget.padding != null) {
       tabBar = Padding(
         padding: widget.padding!,
@@ -2206,9 +2177,6 @@ class _TabsPrimaryDefaultsM3 extends TabBarTheme {
   @override
   Color? get dividerColor => _colors.surfaceVariant;
 
-  @override
-  double? get dividerHeight => 1.0;
-
   @override
   Color? get indicatorColor => _colors.primary;
 
@@ -2256,7 +2224,7 @@ class _TabsPrimaryDefaultsM3 extends TabBarTheme {
   InteractiveInkFeatureFactory? get splashFactory => Theme.of(context).splashFactory;
 
   @override
-  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.startOffset : TabAlignment.fill;
+  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.start : TabAlignment.fill;
 
   static double indicatorWeight = 3.0;
 }
@@ -2273,9 +2241,6 @@ class _TabsSecondaryDefaultsM3 extends TabBarTheme {
   @override
   Color? get dividerColor => _colors.surfaceVariant;
 
-  @override
-  double? get dividerHeight => 1.0;
-
   @override
   Color? get indicatorColor => _colors.primary;
 
@@ -2323,7 +2288,7 @@ class _TabsSecondaryDefaultsM3 extends TabBarTheme {
   InteractiveInkFeatureFactory? get splashFactory => Theme.of(context).splashFactory;
 
   @override
-  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.startOffset : TabAlignment.fill;
+  TabAlignment? get tabAlignment => isScrollable ? TabAlignment.start : TabAlignment.fill;
 }
 
 // END GENERATED TOKEN PROPERTIES - Tabs