packages/flutter/lib/src/cupertino/app.dart - external/github.com/flutter/flutter - Git at Google

 // 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 'package:flutter/widgets.dart';

 import 'button.dart';
 import 'colors.dart';
 import 'icons.dart';
 import 'interface_level.dart';
 import 'localizations.dart';
 import 'route.dart';
 import 'scrollbar.dart';
 import 'theme.dart';

 /// An application that uses Cupertino design.
 ///
 /// A convenience widget that wraps a number of widgets that are commonly
 /// required for an iOS-design targeting application. It builds upon a
 /// [WidgetsApp] by iOS specific defaulting such as fonts and scrolling
 /// physics.
 ///
 /// The [CupertinoApp] configures the top-level [Navigator] to search for routes
 /// in the following order:
 ///
 ///  1. For the `/` route, the [home] property, if non-null, is used.
 ///
 ///  2. Otherwise, the [routes] table is used, if it has an entry for the route.
 ///
 ///  3. Otherwise, [onGenerateRoute] is called, if provided. It should return a
 ///     non-null value for any _valid_ route not handled by [home] and [routes].
 ///
 ///  4. Finally if all else fails [onUnknownRoute] is called.
 ///
 /// If [home], [routes], [onGenerateRoute], and [onUnknownRoute] are all null,
 /// and [builder] is not null, then no [Navigator] is created.
 ///
 /// This widget also configures the observer of the top-level [Navigator] (if
 /// any) to perform [Hero] animations.
 ///
 /// The [CupertinoApp] widget isn't a required ancestor for other Cupertino
 /// widgets, but many Cupertino widgets could depend on the [CupertinoTheme]
 /// widget, which the [CupertinoApp] composes. If you use Material widgets, a
 /// [MaterialApp] also creates the needed dependencies for Cupertino widgets.
 ///
 /// Use this widget with caution on Android since it may produce behaviors
 /// Android users are not expecting such as:
 ///
 ///  * Pages will be dismissible via a back swipe.
 ///  * Scrolling past extremities will trigger iOS-style spring overscrolls.
 ///  * The San Francisco font family is unavailable on Android and can result
 ///    in undefined font behavior.
 ///
 /// {@tool snippet}
 /// This example shows how to create a [CupertinoApp] that disables the "debug"
 /// banner with a [home] route that will be displayed when the app is launched.
 ///
 /// ![The CupertinoApp displays a CupertinoPageScaffold](https://flutter.github.io/assets-for-api-docs/assets/cupertino/basic_cupertino_app.png)
 ///
 /// ```dart
 /// const CupertinoApp(
 ///   home: CupertinoPageScaffold(
 ///     navigationBar: CupertinoNavigationBar(
 ///       middle: Text('Home'),
 ///     ),
 ///     child: Center(child: Icon(CupertinoIcons.share)),
 ///   ),
 ///   debugShowCheckedModeBanner: false,
 /// )
 /// ```
 /// {@end-tool}
 ///
 /// {@tool snippet}
 /// This example shows how to create a [CupertinoApp] that uses the [routes]
 /// `Map` to define the "home" route and an "about" route.
 ///
 /// ```dart
 /// CupertinoApp(
 ///   routes: <String, WidgetBuilder>{
 ///     '/': (BuildContext context) {
 ///       return const CupertinoPageScaffold(
 ///         navigationBar: CupertinoNavigationBar(
 ///           middle: Text('Home Route'),
 ///         ),
 ///         child: Center(child: Icon(CupertinoIcons.share)),
 ///       );
 ///     },
 ///     '/about': (BuildContext context) {
 ///       return const CupertinoPageScaffold(
 ///         navigationBar: CupertinoNavigationBar(
 ///           middle: Text('About Route'),
 ///         ),
 ///         child: Center(child: Icon(CupertinoIcons.share)),
 ///       );
 ///     }
 ///   },
 /// )
 /// ```
 /// {@end-tool}
 ///
 /// {@tool snippet}
 /// This example shows how to create a [CupertinoApp] that defines a [theme] that
 /// will be used for Cupertino widgets in the app.
 ///
 /// ![The CupertinoApp displays a CupertinoPageScaffold with orange-colored icons](https://flutter.github.io/assets-for-api-docs/assets/cupertino/theme_cupertino_app.png)
 ///
 /// ```dart
 /// const CupertinoApp(
 ///   theme: CupertinoThemeData(
 ///     brightness: Brightness.dark,
 ///     primaryColor: CupertinoColors.systemOrange,
 ///   ),
 ///   home: CupertinoPageScaffold(
 ///     navigationBar: CupertinoNavigationBar(
 ///       middle: Text('CupertinoApp Theme'),
 ///     ),
 ///     child: Center(child: Icon(CupertinoIcons.share)),
 ///   ),
 /// )
 /// ```
 /// {@end-tool}
 ///
 /// See also:
 ///
 ///  * [CupertinoPageScaffold], which provides a standard page layout default
 ///    with nav bars.
 ///  * [Navigator], which is used to manage the app's stack of pages.
 ///  * [CupertinoPageRoute], which defines an app page that transitions in an
 ///    iOS-specific way.
 ///  * [WidgetsApp], which defines the basic app elements but does not depend
 ///    on the Cupertino library.
 class CupertinoApp extends StatefulWidget {
   /// Creates a CupertinoApp.
   ///
   /// At least one of [home], [routes], [onGenerateRoute], or [builder] must be
   /// non-null. If only [routes] is given, it must include an entry for the
   /// [Navigator.defaultRouteName] (`/`), since that is the route used when the
   /// application is launched with an intent that specifies an otherwise
   /// unsupported route.
   ///
   /// This class creates an instance of [WidgetsApp].
   ///
   /// The boolean arguments, [routes], and [navigatorObservers], must not be null.
   const CupertinoApp({
     Key? key,
     this.navigatorKey,
     this.home,
     this.theme,
     Map<String, Widget Function(BuildContext)> this.routes = const <String, WidgetBuilder>{},
     this.initialRoute,
     this.onGenerateRoute,
     this.onGenerateInitialRoutes,
     this.onUnknownRoute,
     List<NavigatorObserver> this.navigatorObservers = const <NavigatorObserver>[],
     this.builder,
     this.title = '',
     this.onGenerateTitle,
     this.color,
     this.locale,
     this.localizationsDelegates,
     this.localeListResolutionCallback,
     this.localeResolutionCallback,
     this.supportedLocales = const <Locale>[Locale('en', 'US')],
     this.showPerformanceOverlay = false,
     this.checkerboardRasterCacheImages = false,
     this.checkerboardOffscreenLayers = false,
     this.showSemanticsDebugger = false,
     this.debugShowCheckedModeBanner = true,
     this.shortcuts,
     this.actions,
     this.restorationScopeId,
     this.scrollBehavior,
     this.useInheritedMediaQuery = false,
   }) : assert(routes != null),
        assert(navigatorObservers != null),
        assert(title != null),
        assert(showPerformanceOverlay != null),
        assert(checkerboardRasterCacheImages != null),
        assert(checkerboardOffscreenLayers != null),
        assert(showSemanticsDebugger != null),
        assert(debugShowCheckedModeBanner != null),
        routeInformationProvider = null,
        routeInformationParser = null,
        routerDelegate = null,
        backButtonDispatcher = null,
        super(key: key);

   /// Creates a [CupertinoApp] that uses the [Router] instead of a [Navigator].
   const CupertinoApp.router({
     Key? key,
     this.routeInformationProvider,
     required RouteInformationParser<Object> this.routeInformationParser,
     required RouterDelegate<Object> this.routerDelegate,
     this.backButtonDispatcher,
     this.theme,
     this.builder,
     this.title = '',
     this.onGenerateTitle,
     this.color,
     this.locale,
     this.localizationsDelegates,
     this.localeListResolutionCallback,
     this.localeResolutionCallback,
     this.supportedLocales = const <Locale>[Locale('en', 'US')],
     this.showPerformanceOverlay = false,
     this.checkerboardRasterCacheImages = false,
     this.checkerboardOffscreenLayers = false,
     this.showSemanticsDebugger = false,
     this.debugShowCheckedModeBanner = true,
     this.shortcuts,
     this.actions,
     this.restorationScopeId,
     this.scrollBehavior,
     this.useInheritedMediaQuery = false,
   }) : assert(title != null),
        assert(showPerformanceOverlay != null),
        assert(checkerboardRasterCacheImages != null),
        assert(checkerboardOffscreenLayers != null),
        assert(showSemanticsDebugger != null),
        assert(debugShowCheckedModeBanner != null),
        navigatorObservers = null,
        navigatorKey = null,
        onGenerateRoute = null,
        home = null,
        onGenerateInitialRoutes = null,
        onUnknownRoute = null,
        routes = null,
        initialRoute = null,
        super(key: key);

   /// {@macro flutter.widgets.widgetsApp.navigatorKey}
   final GlobalKey<NavigatorState>? navigatorKey;

   /// {@macro flutter.widgets.widgetsApp.home}
   final Widget? home;

   /// The top-level [CupertinoTheme] styling.
   ///
   /// A null [theme] or unspecified [theme] attributes will default to iOS
   /// system values.
   final CupertinoThemeData? theme;

   /// The application's top-level routing table.
   ///
   /// When a named route is pushed with [Navigator.pushNamed], the route name is
   /// looked up in this map. If the name is present, the associated
   /// [widgets.WidgetBuilder] is used to construct a [CupertinoPageRoute] that
   /// performs an appropriate transition, including [Hero] animations, to the
   /// new route.
   ///
   /// {@macro flutter.widgets.widgetsApp.routes}
   final Map<String, WidgetBuilder>? routes;

   /// {@macro flutter.widgets.widgetsApp.initialRoute}
   final String? initialRoute;

   /// {@macro flutter.widgets.widgetsApp.onGenerateRoute}
   final RouteFactory? onGenerateRoute;

   /// {@macro flutter.widgets.widgetsApp.onGenerateInitialRoutes}
   final InitialRouteListFactory? onGenerateInitialRoutes;

   /// {@macro flutter.widgets.widgetsApp.onUnknownRoute}
   final RouteFactory? onUnknownRoute;

   /// {@macro flutter.widgets.widgetsApp.navigatorObservers}
   final List<NavigatorObserver>? navigatorObservers;

   /// {@macro flutter.widgets.widgetsApp.routeInformationProvider}
   final RouteInformationProvider? routeInformationProvider;

   /// {@macro flutter.widgets.widgetsApp.routeInformationParser}
   final RouteInformationParser<Object>? routeInformationParser;

   /// {@macro flutter.widgets.widgetsApp.routerDelegate}
   final RouterDelegate<Object>? routerDelegate;

   /// {@macro flutter.widgets.widgetsApp.backButtonDispatcher}
   final BackButtonDispatcher? backButtonDispatcher;

   /// {@macro flutter.widgets.widgetsApp.builder}
   final TransitionBuilder? builder;

   /// {@macro flutter.widgets.widgetsApp.title}
   ///
   /// This value is passed unmodified to [WidgetsApp.title].
   final String title;

   /// {@macro flutter.widgets.widgetsApp.onGenerateTitle}
   ///
   /// This value is passed unmodified to [WidgetsApp.onGenerateTitle].
   final GenerateAppTitle? onGenerateTitle;

   /// {@macro flutter.widgets.widgetsApp.color}
   final Color? color;

   /// {@macro flutter.widgets.widgetsApp.locale}
   final Locale? locale;

   /// {@macro flutter.widgets.widgetsApp.localizationsDelegates}
   final Iterable<LocalizationsDelegate<dynamic>>? localizationsDelegates;

   /// {@macro flutter.widgets.widgetsApp.localeListResolutionCallback}
   ///
   /// This callback is passed along to the [WidgetsApp] built by this widget.
   final LocaleListResolutionCallback? localeListResolutionCallback;

   /// {@macro flutter.widgets.LocaleResolutionCallback}
   ///
   /// This callback is passed along to the [WidgetsApp] built by this widget.
   final LocaleResolutionCallback? localeResolutionCallback;

   /// {@macro flutter.widgets.widgetsApp.supportedLocales}
   ///
   /// It is passed along unmodified to the [WidgetsApp] built by this widget.
   final Iterable<Locale> supportedLocales;

   /// Turns on a performance overlay.
   ///
   /// See also:
   ///
   ///  * <https://flutter.dev/debugging/#performanceoverlay>
   final bool showPerformanceOverlay;

   /// Turns on checkerboarding of raster cache images.
   final bool checkerboardRasterCacheImages;

   /// Turns on checkerboarding of layers rendered to offscreen bitmaps.
   final bool checkerboardOffscreenLayers;

   /// Turns on an overlay that shows the accessibility information
   /// reported by the framework.
   final bool showSemanticsDebugger;

   /// {@macro flutter.widgets.widgetsApp.debugShowCheckedModeBanner}
   final bool debugShowCheckedModeBanner;

   /// {@macro flutter.widgets.widgetsApp.shortcuts}
   /// {@tool snippet}
   /// This example shows how to add a single shortcut for
   /// [LogicalKeyboardKey.select] to the default shortcuts without needing to
   /// add your own [Shortcuts] widget.
   ///
   /// Alternatively, you could insert a [Shortcuts] widget with just the mapping
   /// you want to add between the [WidgetsApp] and its child and get the same
   /// effect.
   ///
   /// ```dart
   /// Widget build(BuildContext context) {
   ///   return WidgetsApp(
   ///     shortcuts: <ShortcutActivator, Intent>{
   ///       ... WidgetsApp.defaultShortcuts,
   ///       const SingleActivator(LogicalKeyboardKey.select): const ActivateIntent(),
   ///     },
   ///     color: const Color(0xFFFF0000),
   ///     builder: (BuildContext context, Widget? child) {
   ///       return const Placeholder();
   ///     },
   ///   );
   /// }
   /// ```
   /// {@end-tool}
   /// {@macro flutter.widgets.widgetsApp.shortcuts.seeAlso}
   final Map<ShortcutActivator, Intent>? shortcuts;

   /// {@macro flutter.widgets.widgetsApp.actions}
   /// {@tool snippet}
   /// This example shows how to add a single action handling an
   /// [ActivateAction] to the default actions without needing to
   /// add your own [Actions] widget.
   ///
   /// Alternatively, you could insert a [Actions] widget with just the mapping
   /// you want to add between the [WidgetsApp] and its child and get the same
   /// effect.
   ///
   /// ```dart
   /// Widget build(BuildContext context) {
   ///   return WidgetsApp(
   ///     actions: <Type, Action<Intent>>{
   ///       ... WidgetsApp.defaultActions,
   ///       ActivateAction: CallbackAction<Intent>(
   ///         onInvoke: (Intent intent) {
   ///           // Do something here...
   ///           return null;
   ///         },
   ///       ),
   ///     },
   ///     color: const Color(0xFFFF0000),
   ///     builder: (BuildContext context, Widget? child) {
   ///       return const Placeholder();
   ///     },
   ///   );
   /// }
   /// ```
   /// {@end-tool}
   /// {@macro flutter.widgets.widgetsApp.actions.seeAlso}
   final Map<Type, Action<Intent>>? actions;

   /// {@macro flutter.widgets.widgetsApp.restorationScopeId}
   final String? restorationScopeId;

   /// {@macro flutter.material.materialApp.scrollBehavior}
   ///
   /// When null, defaults to [CupertinoScrollBehavior].
   ///
   /// See also:
   ///
   ///  * [ScrollConfiguration], which controls how [Scrollable] widgets behave
   ///    in a subtree.
   final ScrollBehavior? scrollBehavior;

   /// {@macro flutter.widgets.widgetsApp.useInheritedMediaQuery}
   final bool useInheritedMediaQuery;

   @override
   State<CupertinoApp> createState() => _CupertinoAppState();

   /// The [HeroController] used for Cupertino page transitions.
   ///
   /// Used by [CupertinoTabView] and [CupertinoApp].
   static HeroController createCupertinoHeroController() =>
       HeroController(); // Linear tweening.
 }

 /// Describes how [Scrollable] widgets behave for [CupertinoApp]s.
 ///
 /// {@macro flutter.widgets.scrollBehavior}
 ///
 /// Setting a [CupertinoScrollBehavior] will result in descendant [Scrollable] widgets
 /// using [BouncingScrollPhysics] by default. No [GlowingOverscrollIndicator] is
 /// applied when using a [CupertinoScrollBehavior] either, regardless of platform.
 /// When executing on desktop platforms, a [CupertinoScrollbar] is applied to the child.
 ///
 /// See also:
 ///
 ///  * [ScrollBehavior], the default scrolling behavior extended by this class.
 class CupertinoScrollBehavior extends ScrollBehavior {
   /// Creates a CupertinoScrollBehavior that uses [BouncingScrollPhysics] and
   /// adds [CupertinoScrollbar]s on desktop platforms.
   const CupertinoScrollBehavior();

   @override
   Widget buildScrollbar(BuildContext context , Widget child, ScrollableDetails details) {
     // When modifying this function, consider modifying the implementation in
     // the base class as well.
     switch (getPlatform(context)) {
       case TargetPlatform.linux:
       case TargetPlatform.macOS:
       case TargetPlatform.windows:
         return CupertinoScrollbar(
           controller: details.controller,
           child: child,
         );
       case TargetPlatform.android:
       case TargetPlatform.fuchsia:
       case TargetPlatform.iOS:
         return child;
     }
   }

   @override
   Widget buildOverscrollIndicator(BuildContext context, Widget child, ScrollableDetails details) {
     // No overscroll indicator.
     // When modifying this function, consider modifying the implementation in
     // the base class as well.
     return child;
   }

   @override
   ScrollPhysics getScrollPhysics(BuildContext context) {
     return const BouncingScrollPhysics();
   }
 }

 class _CupertinoAppState extends State<CupertinoApp> {
   late HeroController _heroController;
   bool get _usesRouter => widget.routerDelegate != null;

   @override
   void initState() {
     super.initState();
     _heroController = CupertinoApp.createCupertinoHeroController();
   }

   // Combine the default localization for Cupertino with the ones contributed
   // by the localizationsDelegates parameter, if any. Only the first delegate
   // of a particular LocalizationsDelegate.type is loaded so the
   // localizationsDelegate parameter can be used to override
   // _CupertinoLocalizationsDelegate.
   Iterable<LocalizationsDelegate<dynamic>> get _localizationsDelegates sync* {
     if (widget.localizationsDelegates != null)
       yield* widget.localizationsDelegates!;
     yield DefaultCupertinoLocalizations.delegate;
   }

   Widget _inspectorSelectButtonBuilder(BuildContext context, VoidCallback onPressed) {
     return CupertinoButton.filled(
       padding: EdgeInsets.zero,
       onPressed: onPressed,
       child: const Icon(
         CupertinoIcons.search,
         size: 28.0,
         color: CupertinoColors.white,
       ),
     );
   }

   WidgetsApp _buildWidgetApp(BuildContext context) {
     final CupertinoThemeData effectiveThemeData = CupertinoTheme.of(context);
     final Color color = CupertinoDynamicColor.resolve(widget.color ?? effectiveThemeData.primaryColor, context);

     if (_usesRouter) {
       return WidgetsApp.router(
         key: GlobalObjectKey(this),
         routeInformationProvider: widget.routeInformationProvider,
         routeInformationParser: widget.routeInformationParser!,
         routerDelegate: widget.routerDelegate!,
         backButtonDispatcher: widget.backButtonDispatcher,
         builder: widget.builder,
         title: widget.title,
         onGenerateTitle: widget.onGenerateTitle,
         textStyle: effectiveThemeData.textTheme.textStyle,
         color: color,
         locale: widget.locale,
         localizationsDelegates: _localizationsDelegates,
         localeResolutionCallback: widget.localeResolutionCallback,
         localeListResolutionCallback: widget.localeListResolutionCallback,
         supportedLocales: widget.supportedLocales,
         showPerformanceOverlay: widget.showPerformanceOverlay,
         checkerboardRasterCacheImages: widget.checkerboardRasterCacheImages,
         checkerboardOffscreenLayers: widget.checkerboardOffscreenLayers,
         showSemanticsDebugger: widget.showSemanticsDebugger,
         debugShowCheckedModeBanner: widget.debugShowCheckedModeBanner,
         inspectorSelectButtonBuilder: _inspectorSelectButtonBuilder,
         shortcuts: widget.shortcuts,
         actions: widget.actions,
         restorationScopeId: widget.restorationScopeId,
         useInheritedMediaQuery: widget.useInheritedMediaQuery,
       );
     }
     return WidgetsApp(
       key: GlobalObjectKey(this),
       navigatorKey: widget.navigatorKey,
       navigatorObservers: widget.navigatorObservers!,
       pageRouteBuilder: <T>(RouteSettings settings, WidgetBuilder builder) {
         return CupertinoPageRoute<T>(settings: settings, builder: builder);
       },
       home: widget.home,
       routes: widget.routes!,
       initialRoute: widget.initialRoute,
       onGenerateRoute: widget.onGenerateRoute,
       onGenerateInitialRoutes: widget.onGenerateInitialRoutes,
       onUnknownRoute: widget.onUnknownRoute,
       builder: widget.builder,
       title: widget.title,
       onGenerateTitle: widget.onGenerateTitle,
       textStyle: effectiveThemeData.textTheme.textStyle,
       color: color,
       locale: widget.locale,
       localizationsDelegates: _localizationsDelegates,
       localeResolutionCallback: widget.localeResolutionCallback,
       localeListResolutionCallback: widget.localeListResolutionCallback,
       supportedLocales: widget.supportedLocales,
       showPerformanceOverlay: widget.showPerformanceOverlay,
       checkerboardRasterCacheImages: widget.checkerboardRasterCacheImages,
       checkerboardOffscreenLayers: widget.checkerboardOffscreenLayers,
       showSemanticsDebugger: widget.showSemanticsDebugger,
       debugShowCheckedModeBanner: widget.debugShowCheckedModeBanner,
       inspectorSelectButtonBuilder: _inspectorSelectButtonBuilder,
       shortcuts: widget.shortcuts,
       actions: widget.actions,
       restorationScopeId: widget.restorationScopeId,
       useInheritedMediaQuery: widget.useInheritedMediaQuery,
     );
   }

   @override
   Widget build(BuildContext context) {
     final CupertinoThemeData effectiveThemeData = widget.theme ?? const CupertinoThemeData();

     return ScrollConfiguration(
       behavior: widget.scrollBehavior ?? const CupertinoScrollBehavior(),
       child: CupertinoUserInterfaceLevel(
         data: CupertinoUserInterfaceLevelData.base,
         child: CupertinoTheme(
           data: effectiveThemeData,
           child: HeroControllerScope(
             controller: _heroController,
             child: Builder(
               builder: _buildWidgetApp,
             ),
           ),
         ),
       ),
     );
   }
 }
	// 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 'package:flutter/widgets.dart';

	import 'button.dart';
	import 'colors.dart';
	import 'icons.dart';
	import 'interface_level.dart';
	import 'localizations.dart';
	import 'route.dart';
	import 'scrollbar.dart';
	import 'theme.dart';

	/// An application that uses Cupertino design.
	///
	/// A convenience widget that wraps a number of widgets that are commonly
	/// required for an iOS-design targeting application. It builds upon a
	/// [WidgetsApp] by iOS specific defaulting such as fonts and scrolling
	/// physics.
	///
	/// The [CupertinoApp] configures the top-level [Navigator] to search for routes
	/// in the following order:
	///
	/// 1. For the `/` route, the [home] property, if non-null, is used.
	///
	/// 2. Otherwise, the [routes] table is used, if it has an entry for the route.
	///
	/// 3. Otherwise, [onGenerateRoute] is called, if provided. It should return a
	/// non-null value for any _valid_ route not handled by [home] and [routes].
	///
	/// 4. Finally if all else fails [onUnknownRoute] is called.
	///
	/// If [home], [routes], [onGenerateRoute], and [onUnknownRoute] are all null,
	/// and [builder] is not null, then no [Navigator] is created.
	///
	/// This widget also configures the observer of the top-level [Navigator] (if
	/// any) to perform [Hero] animations.
	///
	/// The [CupertinoApp] widget isn't a required ancestor for other Cupertino
	/// widgets, but many Cupertino widgets could depend on the [CupertinoTheme]
	/// widget, which the [CupertinoApp] composes. If you use Material widgets, a
	/// [MaterialApp] also creates the needed dependencies for Cupertino widgets.
	///
	/// Use this widget with caution on Android since it may produce behaviors
	/// Android users are not expecting such as:
	///
	/// * Pages will be dismissible via a back swipe.
	/// * Scrolling past extremities will trigger iOS-style spring overscrolls.
	/// * The San Francisco font family is unavailable on Android and can result
	/// in undefined font behavior.
	///
	/// {@tool snippet}
	/// This example shows how to create a [CupertinoApp] that disables the "debug"
	/// banner with a [home] route that will be displayed when the app is launched.
	///
	/// ![The CupertinoApp displays a CupertinoPageScaffold](https://flutter.github.io/assets-for-api-docs/assets/cupertino/basic_cupertino_app.png)
	///
	/// ```dart
	/// const CupertinoApp(
	/// home: CupertinoPageScaffold(
	/// navigationBar: CupertinoNavigationBar(
	/// middle: Text('Home'),
	/// ),
	/// child: Center(child: Icon(CupertinoIcons.share)),
	/// ),
	/// debugShowCheckedModeBanner: false,
	/// )
	/// ```
	/// {@end-tool}
	///
	/// {@tool snippet}
	/// This example shows how to create a [CupertinoApp] that uses the [routes]
	/// `Map` to define the "home" route and an "about" route.
	///
	/// ```dart
	/// CupertinoApp(
	/// routes: <String, WidgetBuilder>{
	/// '/': (BuildContext context) {
	/// return const CupertinoPageScaffold(
	/// navigationBar: CupertinoNavigationBar(
	/// middle: Text('Home Route'),
	/// ),
	/// child: Center(child: Icon(CupertinoIcons.share)),
	/// );
	/// },
	/// '/about': (BuildContext context) {
	/// return const CupertinoPageScaffold(
	/// navigationBar: CupertinoNavigationBar(
	/// middle: Text('About Route'),
	/// ),
	/// child: Center(child: Icon(CupertinoIcons.share)),
	/// );
	/// }
	/// },
	/// )
	/// ```
	/// {@end-tool}
	///
	/// {@tool snippet}
	/// This example shows how to create a [CupertinoApp] that defines a [theme] that
	/// will be used for Cupertino widgets in the app.
	///
	/// ![The CupertinoApp displays a CupertinoPageScaffold with orange-colored icons](https://flutter.github.io/assets-for-api-docs/assets/cupertino/theme_cupertino_app.png)
	///
	/// ```dart
	/// const CupertinoApp(
	/// theme: CupertinoThemeData(
	/// brightness: Brightness.dark,
	/// primaryColor: CupertinoColors.systemOrange,
	/// ),
	/// home: CupertinoPageScaffold(
	/// navigationBar: CupertinoNavigationBar(
	/// middle: Text('CupertinoApp Theme'),
	/// ),
	/// child: Center(child: Icon(CupertinoIcons.share)),
	/// ),
	/// )
	/// ```
	/// {@end-tool}
	///
	/// See also:
	///
	/// * [CupertinoPageScaffold], which provides a standard page layout default
	/// with nav bars.
	/// * [Navigator], which is used to manage the app's stack of pages.
	/// * [CupertinoPageRoute], which defines an app page that transitions in an
	/// iOS-specific way.
	/// * [WidgetsApp], which defines the basic app elements but does not depend
	/// on the Cupertino library.
	class CupertinoApp extends StatefulWidget {
	/// Creates a CupertinoApp.
	///
	/// At least one of [home], [routes], [onGenerateRoute], or [builder] must be
	/// non-null. If only [routes] is given, it must include an entry for the
	/// [Navigator.defaultRouteName] (`/`), since that is the route used when the
	/// application is launched with an intent that specifies an otherwise
	/// unsupported route.
	///
	/// This class creates an instance of [WidgetsApp].
	///
	/// The boolean arguments, [routes], and [navigatorObservers], must not be null.
	const CupertinoApp({
	Key? key,
	this.navigatorKey,
	this.home,
	this.theme,
	Map<String, Widget Function(BuildContext)> this.routes = const <String, WidgetBuilder>{},
	this.initialRoute,
	this.onGenerateRoute,
	this.onGenerateInitialRoutes,
	this.onUnknownRoute,
	List<NavigatorObserver> this.navigatorObservers = const <NavigatorObserver>[],
	this.builder,
	this.title = '',
	this.onGenerateTitle,
	this.color,
	this.locale,
	this.localizationsDelegates,
	this.localeListResolutionCallback,
	this.localeResolutionCallback,
	this.supportedLocales = const <Locale>[Locale('en', 'US')],
	this.showPerformanceOverlay = false,
	this.checkerboardRasterCacheImages = false,
	this.checkerboardOffscreenLayers = false,
	this.showSemanticsDebugger = false,
	this.debugShowCheckedModeBanner = true,
	this.shortcuts,
	this.actions,
	this.restorationScopeId,
	this.scrollBehavior,
	this.useInheritedMediaQuery = false,
	}) : assert(routes != null),
	assert(navigatorObservers != null),
	assert(title != null),
	assert(showPerformanceOverlay != null),
	assert(checkerboardRasterCacheImages != null),
	assert(checkerboardOffscreenLayers != null),
	assert(showSemanticsDebugger != null),
	assert(debugShowCheckedModeBanner != null),
	routeInformationProvider = null,
	routeInformationParser = null,
	routerDelegate = null,
	backButtonDispatcher = null,
	super(key: key);

	/// Creates a [CupertinoApp] that uses the [Router] instead of a [Navigator].
	const CupertinoApp.router({
	Key? key,
	this.routeInformationProvider,
	required RouteInformationParser<Object> this.routeInformationParser,
	required RouterDelegate<Object> this.routerDelegate,
	this.backButtonDispatcher,
	this.theme,
	this.builder,
	this.title = '',
	this.onGenerateTitle,
	this.color,
	this.locale,
	this.localizationsDelegates,
	this.localeListResolutionCallback,
	this.localeResolutionCallback,
	this.supportedLocales = const <Locale>[Locale('en', 'US')],
	this.showPerformanceOverlay = false,
	this.checkerboardRasterCacheImages = false,
	this.checkerboardOffscreenLayers = false,
	this.showSemanticsDebugger = false,
	this.debugShowCheckedModeBanner = true,
	this.shortcuts,
	this.actions,
	this.restorationScopeId,
	this.scrollBehavior,
	this.useInheritedMediaQuery = false,
	}) : assert(title != null),
	assert(showPerformanceOverlay != null),
	assert(checkerboardRasterCacheImages != null),
	assert(checkerboardOffscreenLayers != null),
	assert(showSemanticsDebugger != null),
	assert(debugShowCheckedModeBanner != null),
	navigatorObservers = null,
	navigatorKey = null,
	onGenerateRoute = null,
	home = null,
	onGenerateInitialRoutes = null,
	onUnknownRoute = null,
	routes = null,
	initialRoute = null,
	super(key: key);

	/// {@macro flutter.widgets.widgetsApp.navigatorKey}
	final GlobalKey<NavigatorState>? navigatorKey;

	/// {@macro flutter.widgets.widgetsApp.home}
	final Widget? home;

	/// The top-level [CupertinoTheme] styling.
	///
	/// A null [theme] or unspecified [theme] attributes will default to iOS
	/// system values.
	final CupertinoThemeData? theme;

	/// The application's top-level routing table.
	///
	/// When a named route is pushed with [Navigator.pushNamed], the route name is
	/// looked up in this map. If the name is present, the associated
	/// [widgets.WidgetBuilder] is used to construct a [CupertinoPageRoute] that
	/// performs an appropriate transition, including [Hero] animations, to the
	/// new route.
	///
	/// {@macro flutter.widgets.widgetsApp.routes}
	final Map<String, WidgetBuilder>? routes;

	/// {@macro flutter.widgets.widgetsApp.initialRoute}
	final String? initialRoute;

	/// {@macro flutter.widgets.widgetsApp.onGenerateRoute}
	final RouteFactory? onGenerateRoute;

	/// {@macro flutter.widgets.widgetsApp.onGenerateInitialRoutes}
	final InitialRouteListFactory? onGenerateInitialRoutes;

	/// {@macro flutter.widgets.widgetsApp.onUnknownRoute}
	final RouteFactory? onUnknownRoute;

	/// {@macro flutter.widgets.widgetsApp.navigatorObservers}
	final List<NavigatorObserver>? navigatorObservers;

	/// {@macro flutter.widgets.widgetsApp.routeInformationProvider}
	final RouteInformationProvider? routeInformationProvider;

	/// {@macro flutter.widgets.widgetsApp.routeInformationParser}
	final RouteInformationParser<Object>? routeInformationParser;

	/// {@macro flutter.widgets.widgetsApp.routerDelegate}
	final RouterDelegate<Object>? routerDelegate;

	/// {@macro flutter.widgets.widgetsApp.backButtonDispatcher}
	final BackButtonDispatcher? backButtonDispatcher;

	/// {@macro flutter.widgets.widgetsApp.builder}
	final TransitionBuilder? builder;

	/// {@macro flutter.widgets.widgetsApp.title}
	///
	/// This value is passed unmodified to [WidgetsApp.title].
	final String title;

	/// {@macro flutter.widgets.widgetsApp.onGenerateTitle}
	///
	/// This value is passed unmodified to [WidgetsApp.onGenerateTitle].
	final GenerateAppTitle? onGenerateTitle;

	/// {@macro flutter.widgets.widgetsApp.color}
	final Color? color;

	/// {@macro flutter.widgets.widgetsApp.locale}
	final Locale? locale;

	/// {@macro flutter.widgets.widgetsApp.localizationsDelegates}
	final Iterable<LocalizationsDelegate<dynamic>>? localizationsDelegates;

	/// {@macro flutter.widgets.widgetsApp.localeListResolutionCallback}
	///
	/// This callback is passed along to the [WidgetsApp] built by this widget.
	final LocaleListResolutionCallback? localeListResolutionCallback;

	/// {@macro flutter.widgets.LocaleResolutionCallback}
	///
	/// This callback is passed along to the [WidgetsApp] built by this widget.
	final LocaleResolutionCallback? localeResolutionCallback;

	/// {@macro flutter.widgets.widgetsApp.supportedLocales}
	///
	/// It is passed along unmodified to the [WidgetsApp] built by this widget.
	final Iterable<Locale> supportedLocales;

	/// Turns on a performance overlay.
	///
	/// See also:
	///
	/// * <https://flutter.dev/debugging/#performanceoverlay>
	final bool showPerformanceOverlay;

	/// Turns on checkerboarding of raster cache images.
	final bool checkerboardRasterCacheImages;

	/// Turns on checkerboarding of layers rendered to offscreen bitmaps.
	final bool checkerboardOffscreenLayers;

	/// Turns on an overlay that shows the accessibility information
	/// reported by the framework.
	final bool showSemanticsDebugger;

	/// {@macro flutter.widgets.widgetsApp.debugShowCheckedModeBanner}
	final bool debugShowCheckedModeBanner;

	/// {@macro flutter.widgets.widgetsApp.shortcuts}
	/// {@tool snippet}
	/// This example shows how to add a single shortcut for
	/// [LogicalKeyboardKey.select] to the default shortcuts without needing to
	/// add your own [Shortcuts] widget.
	///
	/// Alternatively, you could insert a [Shortcuts] widget with just the mapping
	/// you want to add between the [WidgetsApp] and its child and get the same
	/// effect.
	///
	/// ```dart
	/// Widget build(BuildContext context) {
	/// return WidgetsApp(
	/// shortcuts: <ShortcutActivator, Intent>{
	/// ... WidgetsApp.defaultShortcuts,
	/// const SingleActivator(LogicalKeyboardKey.select): const ActivateIntent(),
	/// },
	/// color: const Color(0xFFFF0000),
	/// builder: (BuildContext context, Widget? child) {
	/// return const Placeholder();
	/// },
	/// );
	/// }
	/// ```
	/// {@end-tool}
	/// {@macro flutter.widgets.widgetsApp.shortcuts.seeAlso}
	final Map<ShortcutActivator, Intent>? shortcuts;

	/// {@macro flutter.widgets.widgetsApp.actions}
	/// {@tool snippet}
	/// This example shows how to add a single action handling an
	/// [ActivateAction] to the default actions without needing to
	/// add your own [Actions] widget.
	///
	/// Alternatively, you could insert a [Actions] widget with just the mapping
	/// you want to add between the [WidgetsApp] and its child and get the same
	/// effect.
	///
	/// ```dart
	/// Widget build(BuildContext context) {
	/// return WidgetsApp(
	/// actions: <Type, Action<Intent>>{
	/// ... WidgetsApp.defaultActions,
	/// ActivateAction: CallbackAction<Intent>(
	/// onInvoke: (Intent intent) {
	/// // Do something here...
	/// return null;
	/// },
	/// ),
	/// },
	/// color: const Color(0xFFFF0000),
	/// builder: (BuildContext context, Widget? child) {
	/// return const Placeholder();
	/// },
	/// );
	/// }
	/// ```
	/// {@end-tool}
	/// {@macro flutter.widgets.widgetsApp.actions.seeAlso}
	final Map<Type, Action<Intent>>? actions;

	/// {@macro flutter.widgets.widgetsApp.restorationScopeId}
	final String? restorationScopeId;

	/// {@macro flutter.material.materialApp.scrollBehavior}
	///
	/// When null, defaults to [CupertinoScrollBehavior].
	///
	/// See also:
	///
	/// * [ScrollConfiguration], which controls how [Scrollable] widgets behave
	/// in a subtree.
	final ScrollBehavior? scrollBehavior;

	/// {@macro flutter.widgets.widgetsApp.useInheritedMediaQuery}
	final bool useInheritedMediaQuery;

	@override
	State<CupertinoApp> createState() => _CupertinoAppState();

	/// The [HeroController] used for Cupertino page transitions.
	///
	/// Used by [CupertinoTabView] and [CupertinoApp].
	static HeroController createCupertinoHeroController() =>
	HeroController(); // Linear tweening.
	}

	/// Describes how [Scrollable] widgets behave for [CupertinoApp]s.
	///
	/// {@macro flutter.widgets.scrollBehavior}
	///
	/// Setting a [CupertinoScrollBehavior] will result in descendant [Scrollable] widgets
	/// using [BouncingScrollPhysics] by default. No [GlowingOverscrollIndicator] is
	/// applied when using a [CupertinoScrollBehavior] either, regardless of platform.
	/// When executing on desktop platforms, a [CupertinoScrollbar] is applied to the child.
	///
	/// See also:
	///
	/// * [ScrollBehavior], the default scrolling behavior extended by this class.
	class CupertinoScrollBehavior extends ScrollBehavior {
	/// Creates a CupertinoScrollBehavior that uses [BouncingScrollPhysics] and
	/// adds [CupertinoScrollbar]s on desktop platforms.
	const CupertinoScrollBehavior();

	@override
	Widget buildScrollbar(BuildContext context , Widget child, ScrollableDetails details) {
	// When modifying this function, consider modifying the implementation in
	// the base class as well.
	switch (getPlatform(context)) {
	case TargetPlatform.linux:
	case TargetPlatform.macOS:
	case TargetPlatform.windows:
	return CupertinoScrollbar(
	controller: details.controller,
	child: child,
	);
	case TargetPlatform.android:
	case TargetPlatform.fuchsia:
	case TargetPlatform.iOS:
	return child;
	}
	}

	@override
	Widget buildOverscrollIndicator(BuildContext context, Widget child, ScrollableDetails details) {
	// No overscroll indicator.
	// When modifying this function, consider modifying the implementation in
	// the base class as well.
	return child;
	}

	@override
	ScrollPhysics getScrollPhysics(BuildContext context) {
	return const BouncingScrollPhysics();
	}
	}

	class _CupertinoAppState extends State<CupertinoApp> {
	late HeroController _heroController;
	bool get _usesRouter => widget.routerDelegate != null;

	@override
	void initState() {
	super.initState();
	_heroController = CupertinoApp.createCupertinoHeroController();
	}

	// Combine the default localization for Cupertino with the ones contributed
	// by the localizationsDelegates parameter, if any. Only the first delegate
	// of a particular LocalizationsDelegate.type is loaded so the
	// localizationsDelegate parameter can be used to override
	// _CupertinoLocalizationsDelegate.
	Iterable<LocalizationsDelegate<dynamic>> get _localizationsDelegates sync* {
	if (widget.localizationsDelegates != null)
	yield* widget.localizationsDelegates!;
	yield DefaultCupertinoLocalizations.delegate;
	}

	Widget _inspectorSelectButtonBuilder(BuildContext context, VoidCallback onPressed) {
	return CupertinoButton.filled(
	padding: EdgeInsets.zero,
	onPressed: onPressed,
	child: const Icon(
	CupertinoIcons.search,
	size: 28.0,
	color: CupertinoColors.white,
	),
	);
	}

	WidgetsApp _buildWidgetApp(BuildContext context) {
	final CupertinoThemeData effectiveThemeData = CupertinoTheme.of(context);
	final Color color = CupertinoDynamicColor.resolve(widget.color ?? effectiveThemeData.primaryColor, context);

	if (_usesRouter) {
	return WidgetsApp.router(
	key: GlobalObjectKey(this),
	routeInformationProvider: widget.routeInformationProvider,
	routeInformationParser: widget.routeInformationParser!,
	routerDelegate: widget.routerDelegate!,
	backButtonDispatcher: widget.backButtonDispatcher,
	builder: widget.builder,
	title: widget.title,
	onGenerateTitle: widget.onGenerateTitle,
	textStyle: effectiveThemeData.textTheme.textStyle,
	color: color,
	locale: widget.locale,
	localizationsDelegates: _localizationsDelegates,
	localeResolutionCallback: widget.localeResolutionCallback,
	localeListResolutionCallback: widget.localeListResolutionCallback,
	supportedLocales: widget.supportedLocales,
	showPerformanceOverlay: widget.showPerformanceOverlay,
	checkerboardRasterCacheImages: widget.checkerboardRasterCacheImages,
	checkerboardOffscreenLayers: widget.checkerboardOffscreenLayers,
	showSemanticsDebugger: widget.showSemanticsDebugger,
	debugShowCheckedModeBanner: widget.debugShowCheckedModeBanner,
	inspectorSelectButtonBuilder: _inspectorSelectButtonBuilder,
	shortcuts: widget.shortcuts,
	actions: widget.actions,
	restorationScopeId: widget.restorationScopeId,
	useInheritedMediaQuery: widget.useInheritedMediaQuery,
	);
	}
	return WidgetsApp(
	key: GlobalObjectKey(this),
	navigatorKey: widget.navigatorKey,
	navigatorObservers: widget.navigatorObservers!,
	pageRouteBuilder: <T>(RouteSettings settings, WidgetBuilder builder) {
	return CupertinoPageRoute<T>(settings: settings, builder: builder);
	},
	home: widget.home,
	routes: widget.routes!,
	initialRoute: widget.initialRoute,
	onGenerateRoute: widget.onGenerateRoute,
	onGenerateInitialRoutes: widget.onGenerateInitialRoutes,
	onUnknownRoute: widget.onUnknownRoute,
	builder: widget.builder,
	title: widget.title,
	onGenerateTitle: widget.onGenerateTitle,
	textStyle: effectiveThemeData.textTheme.textStyle,
	color: color,
	locale: widget.locale,
	localizationsDelegates: _localizationsDelegates,
	localeResolutionCallback: widget.localeResolutionCallback,
	localeListResolutionCallback: widget.localeListResolutionCallback,
	supportedLocales: widget.supportedLocales,
	showPerformanceOverlay: widget.showPerformanceOverlay,
	checkerboardRasterCacheImages: widget.checkerboardRasterCacheImages,
	checkerboardOffscreenLayers: widget.checkerboardOffscreenLayers,
	showSemanticsDebugger: widget.showSemanticsDebugger,
	debugShowCheckedModeBanner: widget.debugShowCheckedModeBanner,
	inspectorSelectButtonBuilder: _inspectorSelectButtonBuilder,
	shortcuts: widget.shortcuts,
	actions: widget.actions,
	restorationScopeId: widget.restorationScopeId,
	useInheritedMediaQuery: widget.useInheritedMediaQuery,
	);
	}

	@override
	Widget build(BuildContext context) {
	final CupertinoThemeData effectiveThemeData = widget.theme ?? const CupertinoThemeData();

	return ScrollConfiguration(
	behavior: widget.scrollBehavior ?? const CupertinoScrollBehavior(),
	child: CupertinoUserInterfaceLevel(
	data: CupertinoUserInterfaceLevelData.base,
	child: CupertinoTheme(
	data: effectiveThemeData,
	child: HeroControllerScope(
	controller: _heroController,
	child: Builder(
	builder: _buildWidgetApp,
	),
	),
	),
	),
	);
	}
	}