// Copyright 2014 The Flutter Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. import 'dart:ui' show lerpDouble; import 'package:flutter/foundation.dart'; import 'package:flutter/widgets.dart'; import 'theme.dart'; /// Defines default property values for descendant [BottomAppBar] widgets. /// /// Descendant widgets obtain the current [BottomAppBarTheme] object using /// `BottomAppBarTheme.of(context)`. Instances of [BottomAppBarTheme] can be /// customized with [BottomAppBarTheme.copyWith]. /// /// Typically a [BottomAppBarTheme] is specified as part of the overall [Theme] /// with [ThemeData.bottomAppBarTheme]. /// /// All [BottomAppBarTheme] properties are `null` by default. When null, the /// [BottomAppBar] constructor provides defaults. /// /// See also: /// /// * [ThemeData], which describes the overall theme information for the /// application. @immutable class BottomAppBarTheme with Diagnosticable { /// Creates a theme that can be used for [ThemeData.bottomAppBarTheme]. const BottomAppBarTheme({ this.color, this.elevation, this.shape, }); /// Default value for [BottomAppBar.color]. /// /// If null, [BottomAppBar] uses [ThemeData.bottomAppBarColor]. final Color? color; /// Default value for [BottomAppBar.elevation]. final double? elevation; /// Default value for [BottomAppBar.shape]. final NotchedShape? shape; /// Creates a copy of this object but with the given fields replaced with the /// new values. BottomAppBarTheme copyWith({ Color? color, double? elevation, NotchedShape? shape, }) { return BottomAppBarTheme( color: color ?? this.color, elevation: elevation ?? this.elevation, shape: shape ?? this.shape, ); } /// The [ThemeData.bottomAppBarTheme] property of the ambient [Theme]. static BottomAppBarTheme of(BuildContext context) { return Theme.of(context).bottomAppBarTheme; } /// Linearly interpolate between two BAB themes. /// /// The argument `t` must not be null. /// /// {@macro dart.ui.shadow.lerp} static BottomAppBarTheme lerp(BottomAppBarTheme? a, BottomAppBarTheme? b, double t) { assert(t != null); return BottomAppBarTheme( color: Color.lerp(a?.color, b?.color, t), elevation: lerpDouble(a?.elevation, b?.elevation, t), shape: t < 0.5 ? a?.shape : b?.shape, ); } @override int get hashCode => Object.hash( color, elevation, shape, ); @override bool operator ==(Object other) { if (identical(this, other)) { return true; } if (other.runtimeType != runtimeType) { return false; } return other is BottomAppBarTheme && other.color == color && other.elevation == elevation && other.shape == shape; } @override void debugFillProperties(DiagnosticPropertiesBuilder properties) { super.debugFillProperties(properties); properties.add(ColorProperty('color', color, defaultValue: null)); properties.add(DiagnosticsProperty<double>('elevation', elevation, defaultValue: null)); properties.add(DiagnosticsProperty<NotchedShape>('shape', shape, defaultValue: null)); } }