BottomAppBar: surfaceTintColor doc wrongly says "If this is null, no overlay will be applied." #124535
Description
Here's the full doc on BottomAppBar.surfaceTintColor currently:
/// The color used as an overlay on [color] to indicate elevation.
///
/// If this is null, no overlay will be applied. Otherwise the
/// color will be composited on top of [color] with an opacity related
/// to [elevation] and used to paint the background of the [BottomAppBar].
///
/// The default is null.
///
/// See [Material.surfaceTintColor] for more details on how this overlay is applied.
final Color? surfaceTintColor;But when surfaceTintColor is null, an overlay is applied. In this code sample, compare a Container with a BottomAppBar that are both given the same gray for their color param:
import 'package:flutter/material.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
Color color = const Color.fromRGBO(90, 90, 90, 1);
return MaterialApp(
theme: Theme.of(context).copyWith(useMaterial3: true),
home: Scaffold(
body: Align(alignment: Alignment.bottomCenter, child: Container(width: 100, height: 100, color: color)),
bottomNavigationBar: BottomAppBar(
color: color,
child: Row(children: [IconButton(onPressed: () {}, icon: const Icon(Icons.menu))])
),
),
);
}
}
The bottom app bar gets its bluish tint from a default surface tint color, which I think in this case is ColorScheme.primary:
Probably the behavior is right, and the doc should be updated to say something like:
/// A custom color for the Material 3 surface-tint elevation effect.
///
/// In Material 3, a "surface tint" with an opacity related to [elevation]
/// will be applied to the [BottomAppBar]'s background.
/// Use this property to override the default color of that tint.
///
/// If this property is null, then [BottomAppBarTheme.surfaceTintColor]
/// of [ThemeData.bottomAppBarTheme] is used.
/// If that is also null, [ColorScheme.surfaceTint] is used.
///
/// Ignored if [ThemeData.useMaterial3] is false.
///
/// The default is null.
///
/// See [Material.surfaceTintColor] for more details on how this overlay is applied.
final Color? surfaceTintColor;