packages/devtools_app/lib/src/shared/screen.dart - external/github.com/flutter/devtools - Git at Google

 // Copyright 2019 The Chromium 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:math' as math;

 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:logging/logging.dart';

 import 'globals.dart';
 import 'primitives/listenable.dart';
 import 'theme.dart';
 import 'ui/icons.dart';
 import 'version.dart';

 final _log = Logger('screen.dart');

 enum ScreenMetaData {
   home('home', icon: Icons.home_rounded),
   inspector(
     'inspector',
     title: 'Flutter Inspector',
     icon: Octicons.deviceMobile,
   ),
   performance('performance', title: 'Performance', icon: Octicons.pulse),
   cpuProfiler('cpu-profiler', title: 'CPU Profiler', icon: Octicons.dashboard),
   memory('memory', title: 'Memory', icon: Octicons.package),
   debugger('debugger', title: 'Debugger', icon: Octicons.bug),
   network('network', title: 'Network', icon: Icons.network_check),
   logging('logging', title: 'Logging', icon: Octicons.clippy),
   provider('provider', title: 'Provider', icon: Icons.attach_file),
   appSize('app-size', title: 'App Size', icon: Octicons.fileZip),
   deepLinks('deep-links', title: 'Deep Links', icon: Icons.link_rounded),
   vmTools('vm-tools', title: 'VM Tools', icon: Icons.settings_applications),
   simple('simple');

   const ScreenMetaData(this.id, {this.title, this.icon});

   final String id;

   final String? title;

   final IconData? icon;
 }

 /// Defines a page shown in the DevTools [TabBar].
 @immutable
 abstract class Screen {
   const Screen(
     this.screenId, {
     this.title,
     this.titleGenerator,
     this.icon,
     this.tabKey,
     this.requiresLibrary,
     this.requiresConnection = true,
     this.requiresDartVm = false,
     this.requiresFlutter = false,
     this.requiresDebugBuild = false,
     this.requiresVmDeveloperMode = false,
     this.worksOffline = false,
     this.shouldShowForFlutterVersion,
     this.showFloatingDebuggerControls = true,
   }) : assert((title == null) || (titleGenerator == null));

   const Screen.conditional({
     required String id,
     String? requiresLibrary,
     bool requiresConnection = true,
     bool requiresDartVm = false,
     bool requiresFlutter = false,
     bool requiresDebugBuild = false,
     bool requiresVmDeveloperMode = false,
     bool worksOffline = false,
     bool Function(FlutterVersion? currentVersion)? shouldShowForFlutterVersion,
     bool showFloatingDebuggerControls = true,
     String? title,
     String Function()? titleGenerator,
     IconData? icon,
     Key? tabKey,
   }) : this(
           id,
           requiresLibrary: requiresLibrary,
           requiresConnection: requiresConnection,
           requiresDartVm: requiresDartVm,
           requiresFlutter: requiresFlutter,
           requiresDebugBuild: requiresDebugBuild,
           requiresVmDeveloperMode: requiresVmDeveloperMode,
           worksOffline: worksOffline,
           shouldShowForFlutterVersion: shouldShowForFlutterVersion,
           showFloatingDebuggerControls: showFloatingDebuggerControls,
           title: title,
           titleGenerator: titleGenerator,
           icon: icon,
           tabKey: tabKey,
         );

   /// Whether to show floating debugger controls if the app is paused.
   ///
   /// If your page is negatively impacted by the app being paused you should
   /// show debugger controls.
   final bool showFloatingDebuggerControls;

   /// Whether to show the console for this screen.
   bool showConsole(bool embed) => false;

   /// Which keyboard shortcuts should be enabled for this screen.
   ShortcutsConfiguration buildKeyboardShortcuts(BuildContext context) =>
       ShortcutsConfiguration.empty();

   final String screenId;

   /// The user-facing name of the page.
   ///
   /// At most, only one of [title] and [titleGenerator] should be non-null.
   final String? title;

   /// A callback that returns the user-facing name of the page.
   ///
   /// At most, only one of [title] and [titleGenerator] should be non-null.
   final String Function()? titleGenerator;

   String get _userFacingTitle => title ?? titleGenerator?.call() ?? '';

   final IconData? icon;

   /// An optional key to use when creating the Tab widget (for use during
   /// testing).
   final Key? tabKey;

   /// Library uri that determines whether to include this screen in DevTools.
   ///
   /// This can either be a full library uri or it can be a prefix. If null, this
   /// screen will be shown if it meets all other criteria.
   ///
   /// Examples:
   ///  * 'package:provider/provider.dart'
   ///  * 'package:provider/'
   final String? requiresLibrary;

   /// Whether this screen requires a running app connection to work.
   final bool requiresConnection;

   /// Whether this screen should only be included when the app is running on the Dart VM.
   final bool requiresDartVm;

   /// Whether this screen should only be included when the app is a Flutter app.
   final bool requiresFlutter;

   /// Whether this screen should only be included when the app is debuggable.
   final bool requiresDebugBuild;

   /// Whether this screen should only be included when VM developer mode is enabled.
   final bool requiresVmDeveloperMode;

   /// Whether this screen works offline and should show in offline mode even if conditions are not met.
   final bool worksOffline;

   /// A callback that will determine whether or not this screen should be
   /// available for a given flutter version.
   final bool Function(FlutterVersion? currentFlutterVersion)?
       shouldShowForFlutterVersion;

   /// Whether this screen should display the isolate selector in the status
   /// line.
   ///
   /// Some screens act on all isolates; for these screens, displaying a
   /// selector doesn't make sense.
   ValueListenable<bool> get showIsolateSelector =>
       const FixedValueListenable<bool>(false);

   /// The id to use to synthesize a help URL.
   ///
   /// If the screen does not have a custom documentation page, this property
   /// should return `null`.
   String? get docPageId => null;

   int get badgeCount => 0;

   double approximateTabWidth(
     TextTheme textTheme, {
     bool includeTabBarSpacing = true,
   }) {
     final title = _userFacingTitle;
     final painter = TextPainter(
       text: TextSpan(text: title),
       textDirection: TextDirection.ltr,
     )..layout();
     const measurementBuffer = 2.0;
     return painter.width +
         denseSpacing +
         defaultIconSize +
         (includeTabBarSpacing ? tabBarSpacing * 2 : 0.0) +
         // Add a small buffer to account for variances between the text painter
         // approximation and the actual measurement.
         measurementBuffer;
   }

   /// Builds the tab to show for this screen in the [DevToolsScaffold]'s main
   /// navbar.
   ///
   /// This will not be used if the [Screen] is the only one shown in the
   /// scaffold.
   Widget buildTab(BuildContext context) {
     final title = _userFacingTitle;
     return ValueListenableBuilder<int>(
       valueListenable:
           serviceManager.errorBadgeManager.errorCountNotifier(screenId),
       builder: (context, count, _) {
         final tab = Tab(
           key: tabKey,
           child: Row(
             children: <Widget>[
               Icon(icon, size: defaultIconSize),
               if (title.isNotEmpty)
                 Padding(
                   padding: const EdgeInsets.only(left: denseSpacing),
                   child: Text(title),
                 ),
             ],
           ),
         );

         if (count > 0) {
           // Calculate the width of the title text so that we can provide an accurate
           // size for the [BadgePainter]
           final painter = TextPainter(
             text: TextSpan(
               text: title,
               style: Theme.of(context).regularTextStyle,
             ),
             textDirection: TextDirection.ltr,
           )..layout();
           final titleWidth = painter.width;

           return LayoutBuilder(
             builder: (context, constraints) {
               return Stack(
                 children: [
                   CustomPaint(
                     size: Size(defaultIconSize + denseSpacing + titleWidth, 0),
                     painter: BadgePainter(
                       number: count,
                       colorScheme: Theme.of(context).colorScheme,
                     ),
                   ),
                   tab,
                 ],
               );
             },
           );
         }

         return tab;
       },
     );
   }

   /// Builds the body to display for this tab.
   Widget build(BuildContext context);

   /// Build a widget to display in the status line.
   ///
   /// If this method returns `null`, then no page specific status is displayed.
   Widget? buildStatus(BuildContext context) {
     return null;
   }
 }

 /// Check whether a screen should be shown in the UI.
 bool shouldShowScreen(Screen screen) {
   _log.finest('shouldShowScreen: ${screen.screenId}');
   if (offlineController.offlineMode.value) {
     _log.finest('for offline mode: returning ${screen.worksOffline}');
     return screen.worksOffline;
   }

   final serviceReady = serviceManager.isServiceAvailable &&
       serviceManager.connectedApp!.connectedAppInitialized;
   if (!serviceReady) {
     if (!screen.requiresConnection) {
       _log.finest('screen does not require connection: returning true');
       return true;
     } else {
       // All of the following checks require a connected vm service, so verify
       // that one exists. This also avoids odd edge cases where we could show
       // screens while the ServiceManager is still initializing.
       _log.finest('service not ready: returning false');
       return false;
     }
   }

   if (screen.requiresLibrary != null) {
     if (serviceManager.isolateManager.mainIsolate.value == null ||
         !serviceManager.libraryUriAvailableNow(screen.requiresLibrary)) {
       _log.finest(
         'screen requires library ${screen.requiresLibrary}: returning false',
       );
       return false;
     }
   }
   if (screen.requiresDartVm) {
     if (serviceManager.connectedApp!.isRunningOnDartVM != true) {
       _log.finest('screen requires Dart VM: returning false');
       return false;
     }
   }
   if (screen.requiresFlutter &&
       serviceManager.connectedApp!.isFlutterAppNow == false) {
     _log.finest('screen requires Flutter: returning false');
     return false;
   }
   if (screen.requiresDebugBuild) {
     if (serviceManager.connectedApp!.isProfileBuildNow == true) {
       _log.finest('screen requires debug build: returning false');
       return false;
     }
   }
   if (screen.requiresVmDeveloperMode) {
     if (!preferences.vmDeveloperModeEnabled.value) {
       _log.finest('screen requires vm developer mode: returning false');
       return false;
     }
   }
   if (screen.shouldShowForFlutterVersion != null) {
     if (serviceManager.connectedApp!.isFlutterAppNow == true &&
         !screen.shouldShowForFlutterVersion!(
           serviceManager.connectedApp!.flutterVersionNow,
         )) {
       _log.finest('screen has flutter version restraints: returning false');
       return false;
     }
   }
   _log.finest('${screen.screenId} screen supported: returning true');
   return true;
 }

 class BadgePainter extends CustomPainter {
   BadgePainter({required this.number, required this.colorScheme});

   final ColorScheme colorScheme;

   final int number;

   @override
   void paint(Canvas canvas, Size size) {
     final paint = Paint()
       ..color = colorScheme.errorContainer
       ..style = PaintingStyle.fill;

     final countPainter = TextPainter(
       text: TextSpan(
         text: '$number',
         style: TextStyle(
           color: colorScheme.onErrorContainer,
           fontWeight: FontWeight.bold,
         ),
       ),
       textDirection: TextDirection.ltr,
     )..layout();

     final badgeWidth = math.max(
       defaultIconSize,
       countPainter.width + denseSpacing,
     );
     canvas.drawOval(
       Rect.fromLTWH(size.width, 0, badgeWidth, defaultIconSize),
       paint,
     );

     countPainter.paint(
       canvas,
       Offset(size.width + (badgeWidth - countPainter.width) / 2, 0),
     );
   }

   @override
   bool shouldRepaint(covariant CustomPainter oldDelegate) {
     if (oldDelegate is BadgePainter) {
       return number != oldDelegate.number;
     }
     return true;
   }
 }

 class ShortcutsConfiguration {
   const ShortcutsConfiguration({
     required this.shortcuts,
     required this.actions,
   }) : assert(shortcuts.length == actions.length);

   factory ShortcutsConfiguration.empty() {
     return ShortcutsConfiguration(shortcuts: {}, actions: {});
   }

   final Map<ShortcutActivator, Intent> shortcuts;
   final Map<Type, Action<Intent>> actions;

   bool get isEmpty => shortcuts.isEmpty && actions.isEmpty;
 }
	// Copyright 2019 The Chromium 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:math' as math;

	import 'package:flutter/foundation.dart';
	import 'package:flutter/material.dart';
	import 'package:logging/logging.dart';

	import 'globals.dart';
	import 'primitives/listenable.dart';
	import 'theme.dart';
	import 'ui/icons.dart';
	import 'version.dart';

	final _log = Logger('screen.dart');

	enum ScreenMetaData {
	home('home', icon: Icons.home_rounded),
	inspector(
	'inspector',
	title: 'Flutter Inspector',
	icon: Octicons.deviceMobile,
	),
	performance('performance', title: 'Performance', icon: Octicons.pulse),
	cpuProfiler('cpu-profiler', title: 'CPU Profiler', icon: Octicons.dashboard),
	memory('memory', title: 'Memory', icon: Octicons.package),
	debugger('debugger', title: 'Debugger', icon: Octicons.bug),
	network('network', title: 'Network', icon: Icons.network_check),
	logging('logging', title: 'Logging', icon: Octicons.clippy),
	provider('provider', title: 'Provider', icon: Icons.attach_file),
	appSize('app-size', title: 'App Size', icon: Octicons.fileZip),
	deepLinks('deep-links', title: 'Deep Links', icon: Icons.link_rounded),
	vmTools('vm-tools', title: 'VM Tools', icon: Icons.settings_applications),
	simple('simple');

	const ScreenMetaData(this.id, {this.title, this.icon});

	final String id;

	final String? title;

	final IconData? icon;
	}

	/// Defines a page shown in the DevTools [TabBar].
	@immutable
	abstract class Screen {
	const Screen(
	this.screenId, {
	this.title,
	this.titleGenerator,
	this.icon,
	this.tabKey,
	this.requiresLibrary,
	this.requiresConnection = true,
	this.requiresDartVm = false,
	this.requiresFlutter = false,
	this.requiresDebugBuild = false,
	this.requiresVmDeveloperMode = false,
	this.worksOffline = false,
	this.shouldShowForFlutterVersion,
	this.showFloatingDebuggerControls = true,
	}) : assert((title == null) \|\| (titleGenerator == null));

	const Screen.conditional({
	required String id,
	String? requiresLibrary,
	bool requiresConnection = true,
	bool requiresDartVm = false,
	bool requiresFlutter = false,
	bool requiresDebugBuild = false,
	bool requiresVmDeveloperMode = false,
	bool worksOffline = false,
	bool Function(FlutterVersion? currentVersion)? shouldShowForFlutterVersion,
	bool showFloatingDebuggerControls = true,
	String? title,
	String Function()? titleGenerator,
	IconData? icon,
	Key? tabKey,
	}) : this(
	id,
	requiresLibrary: requiresLibrary,
	requiresConnection: requiresConnection,
	requiresDartVm: requiresDartVm,
	requiresFlutter: requiresFlutter,
	requiresDebugBuild: requiresDebugBuild,
	requiresVmDeveloperMode: requiresVmDeveloperMode,
	worksOffline: worksOffline,
	shouldShowForFlutterVersion: shouldShowForFlutterVersion,
	showFloatingDebuggerControls: showFloatingDebuggerControls,
	title: title,
	titleGenerator: titleGenerator,
	icon: icon,
	tabKey: tabKey,
	);

	/// Whether to show floating debugger controls if the app is paused.
	///
	/// If your page is negatively impacted by the app being paused you should
	/// show debugger controls.
	final bool showFloatingDebuggerControls;

	/// Whether to show the console for this screen.
	bool showConsole(bool embed) => false;

	/// Which keyboard shortcuts should be enabled for this screen.
	ShortcutsConfiguration buildKeyboardShortcuts(BuildContext context) =>
	ShortcutsConfiguration.empty();

	final String screenId;

	/// The user-facing name of the page.
	///
	/// At most, only one of [title] and [titleGenerator] should be non-null.
	final String? title;

	/// A callback that returns the user-facing name of the page.
	///
	/// At most, only one of [title] and [titleGenerator] should be non-null.
	final String Function()? titleGenerator;

	String get _userFacingTitle => title ?? titleGenerator?.call() ?? '';

	final IconData? icon;

	/// An optional key to use when creating the Tab widget (for use during
	/// testing).
	final Key? tabKey;

	/// Library uri that determines whether to include this screen in DevTools.
	///
	/// This can either be a full library uri or it can be a prefix. If null, this
	/// screen will be shown if it meets all other criteria.
	///
	/// Examples:
	/// * 'package:provider/provider.dart'
	/// * 'package:provider/'
	final String? requiresLibrary;

	/// Whether this screen requires a running app connection to work.
	final bool requiresConnection;

	/// Whether this screen should only be included when the app is running on the Dart VM.
	final bool requiresDartVm;

	/// Whether this screen should only be included when the app is a Flutter app.
	final bool requiresFlutter;

	/// Whether this screen should only be included when the app is debuggable.
	final bool requiresDebugBuild;

	/// Whether this screen should only be included when VM developer mode is enabled.
	final bool requiresVmDeveloperMode;

	/// Whether this screen works offline and should show in offline mode even if conditions are not met.
	final bool worksOffline;

	/// A callback that will determine whether or not this screen should be
	/// available for a given flutter version.
	final bool Function(FlutterVersion? currentFlutterVersion)?
	shouldShowForFlutterVersion;

	/// Whether this screen should display the isolate selector in the status
	/// line.
	///
	/// Some screens act on all isolates; for these screens, displaying a
	/// selector doesn't make sense.
	ValueListenable<bool> get showIsolateSelector =>
	const FixedValueListenable<bool>(false);

	/// The id to use to synthesize a help URL.
	///
	/// If the screen does not have a custom documentation page, this property
	/// should return `null`.
	String? get docPageId => null;

	int get badgeCount => 0;

	double approximateTabWidth(
	TextTheme textTheme, {
	bool includeTabBarSpacing = true,
	}) {
	final title = _userFacingTitle;
	final painter = TextPainter(
	text: TextSpan(text: title),
	textDirection: TextDirection.ltr,
	)..layout();
	const measurementBuffer = 2.0;
	return painter.width +
	denseSpacing +
	defaultIconSize +
	(includeTabBarSpacing ? tabBarSpacing * 2 : 0.0) +
	// Add a small buffer to account for variances between the text painter
	// approximation and the actual measurement.
	measurementBuffer;
	}

	/// Builds the tab to show for this screen in the [DevToolsScaffold]'s main
	/// navbar.
	///
	/// This will not be used if the [Screen] is the only one shown in the
	/// scaffold.
	Widget buildTab(BuildContext context) {
	final title = _userFacingTitle;
	return ValueListenableBuilder<int>(
	valueListenable:
	serviceManager.errorBadgeManager.errorCountNotifier(screenId),
	builder: (context, count, _) {
	final tab = Tab(
	key: tabKey,
	child: Row(
	children: <Widget>[
	Icon(icon, size: defaultIconSize),
	if (title.isNotEmpty)
	Padding(
	padding: const EdgeInsets.only(left: denseSpacing),
	child: Text(title),
	),
	],
	),
	);

	if (count > 0) {
	// Calculate the width of the title text so that we can provide an accurate
	// size for the [BadgePainter]
	final painter = TextPainter(
	text: TextSpan(
	text: title,
	style: Theme.of(context).regularTextStyle,
	),
	textDirection: TextDirection.ltr,
	)..layout();
	final titleWidth = painter.width;

	return LayoutBuilder(
	builder: (context, constraints) {
	return Stack(
	children: [
	CustomPaint(
	size: Size(defaultIconSize + denseSpacing + titleWidth, 0),
	painter: BadgePainter(
	number: count,
	colorScheme: Theme.of(context).colorScheme,
	),
	),
	tab,
	],
	);
	},
	);
	}

	return tab;
	},
	);
	}

	/// Builds the body to display for this tab.
	Widget build(BuildContext context);

	/// Build a widget to display in the status line.
	///
	/// If this method returns `null`, then no page specific status is displayed.
	Widget? buildStatus(BuildContext context) {
	return null;
	}
	}

	/// Check whether a screen should be shown in the UI.
	bool shouldShowScreen(Screen screen) {
	_log.finest('shouldShowScreen: ${screen.screenId}');
	if (offlineController.offlineMode.value) {
	_log.finest('for offline mode: returning ${screen.worksOffline}');
	return screen.worksOffline;
	}

	final serviceReady = serviceManager.isServiceAvailable &&
	serviceManager.connectedApp!.connectedAppInitialized;
	if (!serviceReady) {
	if (!screen.requiresConnection) {
	_log.finest('screen does not require connection: returning true');
	return true;
	} else {
	// All of the following checks require a connected vm service, so verify
	// that one exists. This also avoids odd edge cases where we could show
	// screens while the ServiceManager is still initializing.
	_log.finest('service not ready: returning false');
	return false;
	}
	}

	if (screen.requiresLibrary != null) {
	if (serviceManager.isolateManager.mainIsolate.value == null \|\|
	!serviceManager.libraryUriAvailableNow(screen.requiresLibrary)) {
	_log.finest(
	'screen requires library ${screen.requiresLibrary}: returning false',
	);
	return false;
	}
	}
	if (screen.requiresDartVm) {
	if (serviceManager.connectedApp!.isRunningOnDartVM != true) {
	_log.finest('screen requires Dart VM: returning false');
	return false;
	}
	}
	if (screen.requiresFlutter &&
	serviceManager.connectedApp!.isFlutterAppNow == false) {
	_log.finest('screen requires Flutter: returning false');
	return false;
	}
	if (screen.requiresDebugBuild) {
	if (serviceManager.connectedApp!.isProfileBuildNow == true) {
	_log.finest('screen requires debug build: returning false');
	return false;
	}
	}
	if (screen.requiresVmDeveloperMode) {
	if (!preferences.vmDeveloperModeEnabled.value) {
	_log.finest('screen requires vm developer mode: returning false');
	return false;
	}
	}
	if (screen.shouldShowForFlutterVersion != null) {
	if (serviceManager.connectedApp!.isFlutterAppNow == true &&
	!screen.shouldShowForFlutterVersion!(
	serviceManager.connectedApp!.flutterVersionNow,
	)) {
	_log.finest('screen has flutter version restraints: returning false');
	return false;
	}
	}
	_log.finest('${screen.screenId} screen supported: returning true');
	return true;
	}

	class BadgePainter extends CustomPainter {
	BadgePainter({required this.number, required this.colorScheme});

	final ColorScheme colorScheme;

	final int number;

	@override
	void paint(Canvas canvas, Size size) {
	final paint = Paint()
	..color = colorScheme.errorContainer
	..style = PaintingStyle.fill;

	final countPainter = TextPainter(
	text: TextSpan(
	text: '$number',
	style: TextStyle(
	color: colorScheme.onErrorContainer,
	fontWeight: FontWeight.bold,
	),
	),
	textDirection: TextDirection.ltr,
	)..layout();

	final badgeWidth = math.max(
	defaultIconSize,
	countPainter.width + denseSpacing,
	);
	canvas.drawOval(
	Rect.fromLTWH(size.width, 0, badgeWidth, defaultIconSize),
	paint,
	);

	countPainter.paint(
	canvas,
	Offset(size.width + (badgeWidth - countPainter.width) / 2, 0),
	);
	}

	@override
	bool shouldRepaint(covariant CustomPainter oldDelegate) {
	if (oldDelegate is BadgePainter) {
	return number != oldDelegate.number;
	}
	return true;
	}
	}

	class ShortcutsConfiguration {
	const ShortcutsConfiguration({
	required this.shortcuts,
	required this.actions,
	}) : assert(shortcuts.length == actions.length);

	factory ShortcutsConfiguration.empty() {
	return ShortcutsConfiguration(shortcuts: {}, actions: {});
	}

	final Map<ShortcutActivator, Intent> shortcuts;
	final Map<Type, Action<Intent>> actions;

	bool get isEmpty => shortcuts.isEmpty && actions.isEmpty;
	}