update comments (#115603)

Author: hannah-hyj

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

@@ -39,19 +39,19 @@ class BottomSheetThemeData with Diagnosticable {
     this.constraints,
   });
 
-  /// Default value for [BottomSheet.backgroundColor].
+  /// Overrides the default value for [BottomSheet.backgroundColor].
   ///
   /// If null, [BottomSheet] defaults to [Material]'s default.
   final Color? backgroundColor;
 
-  /// Default value for surfaceTintColor.
+  /// Overrides the default value for surfaceTintColor.
   ///
   /// If null, [BottomSheet] will not display an overlay color.
   ///
   /// See [Material.surfaceTintColor] for more details.
   final Color? surfaceTintColor;
 
-  /// Default value for [BottomSheet.elevation].
+  /// Overrides the default value for [BottomSheet.elevation].
   ///
   /// {@macro flutter.material.material.elevation}
   ///
@@ -62,21 +62,21 @@ class BottomSheetThemeData with Diagnosticable {
   /// as a modal bottom sheet.
   final Color? modalBackgroundColor;
 
-  /// Default value for barrier color when the Bottom sheet is presented as
+  /// Overrides the default value for barrier color when the Bottom sheet is presented as
   /// a modal bottom sheet.
   final Color? modalBarrierColor;
 
   /// Value for [BottomSheet.elevation] when the Bottom sheet is presented as a
   /// modal bottom sheet.
   final double? modalElevation;
 
-  /// Default value for [BottomSheet.shape].
+  /// Overrides the default value for [BottomSheet.shape].
   ///
   /// If null, no overriding shape is specified for [BottomSheet], so the
   /// [BottomSheet] is rectangular.
   final ShapeBorder? shape;
 
-  /// Default value for [BottomSheet.clipBehavior].
+  /// Overrides the default value for [BottomSheet.clipBehavior].
   ///
   /// If null, [BottomSheet] uses [Clip.none].
   final Clip? clipBehavior;

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

@@ -42,40 +42,40 @@ class CardTheme with Diagnosticable {
     this.shape,
   }) : assert(elevation == null || elevation >= 0.0);
 
-  /// Default value for [Card.clipBehavior].
+  /// Overrides the default value for [Card.clipBehavior].
   ///
   /// If null, [Card] uses [Clip.none].
   final Clip? clipBehavior;
 
-  /// Default value for [Card.color].
+  /// Overrides the default value for [Card.color].
   ///
   /// If null, [Card] uses [ThemeData.cardColor].
   final Color? color;
 
-  /// Default value for [Card.shadowColor].
+  /// Overrides the default value for [Card.shadowColor].
   ///
   /// If null, [Card] defaults to fully opaque black.
   final Color? shadowColor;
 
-  /// Default value for [Card.surfaceTintColor].
+  /// Overrides the default value for [Card.surfaceTintColor].
   ///
   /// If null, [Card] will not display an overlay color.
   ///
   /// See [Material.surfaceTintColor] for more details.
   final Color? surfaceTintColor;
 
-  /// Default value for [Card.elevation].
+  /// Overrides the default value for [Card.elevation].
   ///
   /// If null, [Card] uses a default of 1.0.
   final double? elevation;
 
-  /// Default value for [Card.margin].
+  /// Overrides the default value for [Card.margin].
   ///
   /// If null, [Card] uses a default margin of 4.0 logical pixels on all sides:
   /// `EdgeInsets.all(4.0)`.
   final EdgeInsetsGeometry? margin;
 
-  /// Default value for [Card.shape].
+  /// Overrides the default value for [Card.shape].
   ///
   /// If null, [Card] then uses a [RoundedRectangleBorder] with a circular
   /// corner radius of 4.0.

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

@@ -66,18 +66,18 @@ class SnackBarThemeData with Diagnosticable {
             width == null ||
                 (width != null && identical(behavior, SnackBarBehavior.floating)),
             'Width can only be set if behaviour is SnackBarBehavior.floating');
-  /// Default value for [SnackBar.backgroundColor].
+  /// Overrides the default value for [SnackBar.backgroundColor].
   ///
   /// If null, [SnackBar] defaults to dark grey: `Color(0xFF323232)`.
   final Color? backgroundColor;
 
-  /// Default value for [SnackBarAction.textColor].
+  /// Overrides the default value for [SnackBarAction.textColor].
   ///
   /// If null, [SnackBarAction] defaults to [ColorScheme.secondary] of
   /// [ThemeData.colorScheme] .
   final Color? actionTextColor;
 
-  /// Default value for [SnackBarAction.disabledTextColor].
+  /// Overrides the default value for [SnackBarAction.disabledTextColor].
   ///
   /// If null, [SnackBarAction] defaults to [ColorScheme.onSurface] with its
   /// opacity set to 0.30 if the [Theme]'s brightness is [Brightness.dark], 0.38
@@ -89,12 +89,12 @@ class SnackBarThemeData with Diagnosticable {
   /// If null, [SnackBar] defines its default.
   final TextStyle? contentTextStyle;
 
-  /// Default value for [SnackBar.elevation].
+  /// Overrides the default value for [SnackBar.elevation].
   ///
   /// If null, [SnackBar] uses a default of 6.0.
   final double? elevation;
 
-  /// Default value for [SnackBar.shape].
+  /// Overrides the default value for [SnackBar.shape].
   ///
   /// If null, [SnackBar] provides different defaults depending on the
   /// [SnackBarBehavior]. For [SnackBarBehavior.fixed], no overriding shape is
@@ -103,12 +103,12 @@ class SnackBarThemeData with Diagnosticable {
   /// circular corner radius of 4.0.
   final ShapeBorder? shape;
 
-  /// Default value for [SnackBar.behavior].
+  /// Overrides the default value for [SnackBar.behavior].
   ///
   /// If null, [SnackBar] will default to [SnackBarBehavior.fixed].
   final SnackBarBehavior? behavior;
 
-  /// Default value for [SnackBar.width].
+  /// Overrides the default value for [SnackBar.width].
   ///
   /// If this property is null, then the snack bar will take up the full device
   /// width less the margin. This value is only used when [behavior] is

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

@@ -40,35 +40,35 @@ class TabBarTheme with Diagnosticable {
     this.mouseCursor,
   });
 
-  /// Default value for [TabBar.indicator].
+  /// Overrides the default value for [TabBar.indicator].
   final Decoration? indicator;
 
-  /// Default value for [TabBar.indicatorSize].
+  /// Overrides the default value for [TabBar.indicatorSize].
   final TabBarIndicatorSize? indicatorSize;
 
-  /// Default value for [TabBar.labelColor].
+  /// Overrides the default value for [TabBar.labelColor].
   final Color? labelColor;
 
-  /// Default value for [TabBar.labelPadding].
+  /// Overrides the default value for [TabBar.labelPadding].
   ///
   /// If there are few tabs with both icon and text and few
   /// tabs with only icon or text, this padding is vertically
   /// adjusted to provide uniform padding to all tabs.
   final EdgeInsetsGeometry? labelPadding;
 
-  /// Default value for [TabBar.labelStyle].
+  /// Overrides the default value for [TabBar.labelStyle].
   final TextStyle? labelStyle;
 
-  /// Default value for [TabBar.unselectedLabelColor].
+  /// Overrides the default value for [TabBar.unselectedLabelColor].
   final Color? unselectedLabelColor;
 
-  /// Default value for [TabBar.unselectedLabelStyle].
+  /// Overrides the default value for [TabBar.unselectedLabelStyle].
   final TextStyle? unselectedLabelStyle;
 
-  /// Default value for [TabBar.overlayColor].
+  /// Overrides the default value for [TabBar.overlayColor].
   final MaterialStateProperty<Color?>? overlayColor;
 
-  /// Default value for [TabBar.splashFactory].
+  /// Overrides the default value for [TabBar.splashFactory].
   final InteractiveInkFeatureFactory? splashFactory;
 
   /// {@macro flutter.material.tabs.mouseCursor}