ui/native_theme/native_theme_mac.mm - chromium/src - Git at Google

 // Copyright (c) 2013 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.

 #include "ui/native_theme/native_theme_mac.h"

 #import <Cocoa/Cocoa.h>
 #include <stddef.h>

 #include "base/command_line.h"
 #include "base/mac/mac_util.h"
 #include "base/mac/scoped_block.h"
 #include "base/macros.h"
 #import "skia/ext/skia_utils_mac.h"
 #include "ui/base/ui_base_features.h"
 #include "ui/base/ui_base_switches.h"
 #include "ui/gfx/color_palette.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/skia_util.h"
 #include "ui/native_theme/common_theme.h"
 #include "ui/native_theme/native_theme_aura.h"

 namespace {

 bool IsDarkMode() {
   if (@available(macOS 10.14, *)) {
     NSAppearanceName appearance =
         [[NSApp effectiveAppearance] bestMatchFromAppearancesWithNames:@[
           NSAppearanceNameAqua, NSAppearanceNameDarkAqua
         ]];
     return [appearance isEqual:NSAppearanceNameDarkAqua];
   }
   return false;
 }

 bool IsHighContrast() {
   NSWorkspace* workspace = [NSWorkspace sharedWorkspace];
   if ([workspace respondsToSelector:@selector
                  (accessibilityDisplayShouldIncreaseContrast)]) {
     return workspace.accessibilityDisplayShouldIncreaseContrast;
   }
   return false;
 }
 }  // namespace

 @interface NSWorkspace (Redeclarations)

 @property(readonly) BOOL accessibilityDisplayShouldIncreaseContrast;

 @end

 // Helper object to respond to light mode/dark mode changeovers.
 @interface NativeThemeEffectiveAppearanceObserver : NSObject
 @end

 @implementation NativeThemeEffectiveAppearanceObserver {
   base::mac::ScopedBlock<void (^)()> _handler;
 }

 - (instancetype)initWithHandler:(void (^)())handler {
   self = [super init];
   if (self) {
     _handler.reset([handler copy]);
     if (@available(macOS 10.14, *)) {
       [NSApp addObserver:self
               forKeyPath:@"effectiveAppearance"
                  options:0
                  context:nullptr];
     }
   }
   return self;
 }

 - (void)dealloc {
   if (@available(macOS 10.14, *)) {
     [NSApp removeObserver:self forKeyPath:@"effectiveAppearance"];
   }
   [super dealloc];
 }

 - (void)observeValueForKeyPath:(NSString*)forKeyPath
                       ofObject:(id)object
                         change:(NSDictionary*)change
                        context:(void*)context {
   _handler.get()();
 }

 @end

 namespace {

 // Helper to make indexing an array by an enum class easier.
 template <class KEY, class VALUE>
 struct EnumArray {
   VALUE& operator[](const KEY& key) { return array[static_cast<size_t>(key)]; }
   VALUE array[static_cast<size_t>(KEY::COUNT)];
 };

 // NSColor has a number of methods that return system colors (i.e. controlled by
 // user preferences). This function converts the color given by an NSColor class
 // method to an SkColor. Official documentation suggests developers only rely on
 // +[NSColor selectedTextBackgroundColor] and +[NSColor selectedControlColor],
 // but other colors give a good baseline. For many, a gradient is involved; the
 // palette chosen based on the enum value given by +[NSColor currentColorTint].
 // Apple's documentation also suggests to use NSColorList, but the system color
 // list is just populated with class methods on NSColor.
 SkColor NSSystemColorToSkColor(NSColor* color) {
   // System colors use the an NSNamedColorSpace called "System", so first step
   // is to convert the color into something that can be worked with.
   NSColor* device_color =
       [color colorUsingColorSpace:[NSColorSpace deviceRGBColorSpace]];
   if (device_color)
     return skia::NSDeviceColorToSkColor(device_color);

   // Sometimes the conversion is not possible, but we can get an approximation
   // by going through a CGColorRef. Note that simply using NSColor methods for
   // accessing components for system colors results in exceptions like
   // "-numberOfComponents not valid for the NSColor NSNamedColorSpace System
   // windowBackgroundColor; need to first convert colorspace." Hence the
   // conversion first to CGColor.
   CGColorRef cg_color = [color CGColor];
   const size_t component_count = CGColorGetNumberOfComponents(cg_color);
   if (component_count == 4)
     return skia::CGColorRefToSkColor(cg_color);

   CHECK(component_count == 1 || component_count == 2);
   // 1-2 components means a grayscale channel and maybe an alpha channel, which
   // CGColorRefToSkColor will not like. But RGB is additive, so the conversion
   // is easy (RGB to grayscale is less easy).
   const CGFloat* components = CGColorGetComponents(cg_color);
   CGFloat alpha = component_count == 2 ? components[1] : 1.0;
   return SkColorSetARGB(SkScalarRoundToInt(255.0 * alpha),
                         SkScalarRoundToInt(255.0 * components[0]),
                         SkScalarRoundToInt(255.0 * components[0]),
                         SkScalarRoundToInt(255.0 * components[0]));
 }

 // Converts an SkColor to grayscale by using luminance for all three components.
 // Experimentally, this seems to produce a better result than a flat average or
 // a min/max average for UI controls.
 SkColor ColorToGrayscale(SkColor color) {
   SkScalar luminance = SkColorGetR(color) * 0.21 +
                        SkColorGetG(color) * 0.72 +
                        SkColorGetB(color) * 0.07;
   uint8_t component = SkScalarRoundToInt(luminance);
   return SkColorSetARGB(SkColorGetA(color), component, component, component);
 }

 }  // namespace

 namespace ui {

 // static
 NativeTheme* NativeTheme::GetInstanceForWeb() {
   if (features::IsFormControlsRefreshEnabled())
     return NativeThemeAura::web_instance();
   return NativeThemeMac::instance();
 }

 // static
 NativeTheme* NativeTheme::GetInstanceForNativeUi() {
   return NativeThemeMac::instance();
 }

 NativeTheme* NativeTheme::GetInstanceForDarkUI() {
   static base::NoDestructor<NativeThemeMac> s_native_theme(false, true);
   return s_native_theme.get();
 }

 // static
 bool NativeTheme::SystemDarkModeSupported() {
   if (@available(macOS 10.14, *)) {
     return true;
   }
   return false;
 }

 // static
 NativeThemeMac* NativeThemeMac::instance() {
   static base::NoDestructor<NativeThemeMac> s_native_theme(true, false);
   return s_native_theme.get();
 }

 // static
 SkColor NativeThemeMac::ApplySystemControlTint(SkColor color) {
   if ([NSColor currentControlTint] == NSGraphiteControlTint)
     return ColorToGrayscale(color);
   return color;
 }

 SkColor NativeThemeMac::GetSystemColor(ColorId color_id,
                                        ColorScheme color_scheme) const {
   if (color_scheme == ColorScheme::kDefault)
     color_scheme = GetDefaultSystemColorScheme();

   if ((color_scheme == ColorScheme::kDark) != IsDarkMode())
     return NativeTheme::GetSystemColor(color_id, color_scheme);

   // Empirically, currentAppearance is incorrect when switching
   // appearances. It's unclear exactly why right now, so work
   // around it for the time being by resynchronizing.
   if (@available(macOS 10.14, *)) {
     NSAppearance* effective_appearance = [NSApp effectiveAppearance];
     if (![effective_appearance isEqual:[NSAppearance currentAppearance]]) {
       [NSAppearance setCurrentAppearance:effective_appearance];
     }
   }

   if (UsesHighContrastColors()) {
     switch (color_id) {
       case kColorId_SelectedMenuItemForegroundColor:
         return color_scheme == ColorScheme::kDark ? SK_ColorBLACK
                                                   : SK_ColorWHITE;
       case kColorId_FocusedMenuItemBackgroundColor:
         return color_scheme == ColorScheme::kDark ? SK_ColorLTGRAY
                                                   : SK_ColorDKGRAY;
       default:
         break;
     }
   }
   // Even with --secondary-ui-md, menus use the platform colors and styling, and
   // Mac has a couple of specific color overrides, documented below.
   switch (color_id) {
     case kColorId_EnabledMenuItemForegroundColor:
       return NSSystemColorToSkColor([NSColor controlTextColor]);
     case kColorId_DisabledMenuItemForegroundColor:
       return NSSystemColorToSkColor([NSColor disabledControlTextColor]);
     case kColorId_MenuSeparatorColor:
       return color_scheme == ColorScheme::kDark
                  ? SkColorSetA(gfx::kGoogleGrey800, 0xCC)
                  : SkColorSetA(SK_ColorBLACK, 0x26);
     case kColorId_MenuBorderColor:
       return SkColorSetA(SK_ColorBLACK, 0x60);

     // Mac has a different "pressed button" styling because it doesn't use
     // ripples.
     case kColorId_ButtonPressedShade:
       return SkColorSetA(SK_ColorBLACK, 0x10);

     // There's a system setting General > Highlight color which sets the
     // background color for text selections. We honor that setting.
     // TODO(ellyjones): Listen for NSSystemColorsDidChangeNotification somewhere
     // and propagate it to the View hierarchy.
     case kColorId_LabelTextSelectionBackgroundFocused:
     case kColorId_TextfieldSelectionBackgroundFocused:
       return NSSystemColorToSkColor([NSColor selectedTextBackgroundColor]);

     case kColorId_FocusedBorderColor:
       return SkColorSetA(
           NSSystemColorToSkColor([NSColor keyboardFocusIndicatorColor]),
           0x66);

     case kColorId_TableBackgroundAlternate:
       if (@available(macOS 10.14, *)) {
         return NSSystemColorToSkColor(
             NSColor.alternatingContentBackgroundColors[1]);
       }
       return NSSystemColorToSkColor(
           NSColor.controlAlternatingRowBackgroundColors[1]);

     default:
       break;
   }

   return ApplySystemControlTint(
       NativeTheme::GetSystemColor(color_id, color_scheme));
 }

 void NativeThemeMac::PaintMenuPopupBackground(
     cc::PaintCanvas* canvas,
     const gfx::Size& size,
     const MenuBackgroundExtraParams& menu_background,
     ColorScheme color_scheme) const {
   cc::PaintFlags flags;
   flags.setAntiAlias(true);
   flags.setColor(GetSystemColor(kColorId_MenuBackgroundColor, color_scheme));
   const SkScalar radius = SkIntToScalar(menu_background.corner_radius);
   SkRect rect = gfx::RectToSkRect(gfx::Rect(size));
   canvas->drawRoundRect(rect, radius, radius, flags);
 }

 void NativeThemeMac::PaintMenuItemBackground(
     cc::PaintCanvas* canvas,
     State state,
     const gfx::Rect& rect,
     const MenuItemExtraParams& menu_item,
     ColorScheme color_scheme) const {
   switch (state) {
     case NativeTheme::kNormal:
     case NativeTheme::kDisabled:
       // Draw nothing over the regular background.
       break;
     case NativeTheme::kHovered:
       PaintSelectedMenuItem(canvas, rect, color_scheme);
       break;
     default:
       NOTREACHED();
       break;
   }
 }

 NativeThemeMac::NativeThemeMac(bool configure_web_instance,
                                bool should_only_use_dark_colors)
     : NativeThemeBase(should_only_use_dark_colors) {
   if (!should_only_use_dark_colors)
     InitializeDarkModeStateAndObserver();

   if (!IsForcedHighContrast()) {
     set_high_contrast(IsHighContrast());
     __block auto theme = this;
     high_contrast_notification_token_ =
         [[[NSWorkspace sharedWorkspace] notificationCenter]
             addObserverForName:
                 NSWorkspaceAccessibilityDisplayOptionsDidChangeNotification
                         object:nil
                          queue:nil
                     usingBlock:^(NSNotification* notification) {
                       theme->set_high_contrast(IsHighContrast());
                       theme->NotifyObservers();
                     }];
   }

   if (configure_web_instance)
     ConfigureWebInstance();
 }

 NativeThemeMac::~NativeThemeMac() {
   [[NSNotificationCenter defaultCenter]
       removeObserver:high_contrast_notification_token_];
 }

 void NativeThemeMac::PaintSelectedMenuItem(cc::PaintCanvas* canvas,
                                            const gfx::Rect& rect,
                                            ColorScheme color_scheme) const {
   // Draw the background.
   cc::PaintFlags flags;
   flags.setColor(
       GetSystemColor(kColorId_FocusedMenuItemBackgroundColor, color_scheme));
   canvas->drawRect(gfx::RectToSkRect(rect), flags);
 }

 void NativeThemeMac::InitializeDarkModeStateAndObserver() {
   __block auto theme = this;
   set_use_dark_colors(IsDarkMode());
   set_preferred_color_scheme(CalculatePreferredColorScheme());
   appearance_observer_.reset(
       [[NativeThemeEffectiveAppearanceObserver alloc] initWithHandler:^{
         theme->set_use_dark_colors(IsDarkMode());
         theme->set_preferred_color_scheme(CalculatePreferredColorScheme());
         theme->NotifyObservers();
       }]);
 }

 void NativeThemeMac::ConfigureWebInstance() {
   if (!features::IsFormControlsRefreshEnabled())
     return;

   // For FormControlsRefresh, NativeThemeAura is used as web instance so we need
   // to initialize its state.
   NativeTheme* web_instance = NativeTheme::GetInstanceForWeb();
   web_instance->set_use_dark_colors(IsDarkMode());
   web_instance->set_preferred_color_scheme(CalculatePreferredColorScheme());
   web_instance->set_high_contrast(IsHighContrast());

   // Add the web native theme as an observer to stay in sync with dark mode,
   // high contrast, and preferred color scheme changes.
   color_scheme_observer_ =
       std::make_unique<NativeTheme::ColorSchemeNativeThemeObserver>(
           NativeTheme::GetInstanceForWeb());
   AddObserver(color_scheme_observer_.get());
 }

 }  // namespace ui
	// Copyright (c) 2013 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.

	#include "ui/native_theme/native_theme_mac.h"

	#import <Cocoa/Cocoa.h>
	#include <stddef.h>

	#include "base/command_line.h"
	#include "base/mac/mac_util.h"
	#include "base/mac/scoped_block.h"
	#include "base/macros.h"
	#import "skia/ext/skia_utils_mac.h"
	#include "ui/base/ui_base_features.h"
	#include "ui/base/ui_base_switches.h"
	#include "ui/gfx/color_palette.h"
	#include "ui/gfx/geometry/rect.h"
	#include "ui/gfx/skia_util.h"
	#include "ui/native_theme/common_theme.h"
	#include "ui/native_theme/native_theme_aura.h"

	namespace {

	bool IsDarkMode() {
	if (@available(macOS 10.14, *)) {
	NSAppearanceName appearance =
	[[NSApp effectiveAppearance] bestMatchFromAppearancesWithNames:@[
	NSAppearanceNameAqua, NSAppearanceNameDarkAqua
	]];
	return [appearance isEqual:NSAppearanceNameDarkAqua];
	}
	return false;
	}

	bool IsHighContrast() {
	NSWorkspace* workspace = [NSWorkspace sharedWorkspace];
	if ([workspace respondsToSelector:@selector
	(accessibilityDisplayShouldIncreaseContrast)]) {
	return workspace.accessibilityDisplayShouldIncreaseContrast;
	}
	return false;
	}
	} // namespace

	@interface NSWorkspace (Redeclarations)

	@property(readonly) BOOL accessibilityDisplayShouldIncreaseContrast;

	@end

	// Helper object to respond to light mode/dark mode changeovers.
	@interface NativeThemeEffectiveAppearanceObserver : NSObject
	@end

	@implementation NativeThemeEffectiveAppearanceObserver {
	base::mac::ScopedBlock<void (^)()> _handler;
	}

	- (instancetype)initWithHandler:(void (^)())handler {
	self = [super init];
	if (self) {
	_handler.reset([handler copy]);
	if (@available(macOS 10.14, *)) {
	[NSApp addObserver:self
	forKeyPath:@"effectiveAppearance"
	options:0
	context:nullptr];
	}
	}
	return self;
	}

	- (void)dealloc {
	if (@available(macOS 10.14, *)) {
	[NSApp removeObserver:self forKeyPath:@"effectiveAppearance"];
	}
	[super dealloc];
	}

	- (void)observeValueForKeyPath:(NSString*)forKeyPath
	ofObject:(id)object
	change:(NSDictionary*)change
	context:(void*)context {
	_handler.get()();
	}

	@end

	namespace {

	// Helper to make indexing an array by an enum class easier.
	template <class KEY, class VALUE>
	struct EnumArray {
	VALUE& operator[](const KEY& key) { return array[static_cast<size_t>(key)]; }
	VALUE array[static_cast<size_t>(KEY::COUNT)];
	};

	// NSColor has a number of methods that return system colors (i.e. controlled by
	// user preferences). This function converts the color given by an NSColor class
	// method to an SkColor. Official documentation suggests developers only rely on
	// +[NSColor selectedTextBackgroundColor] and +[NSColor selectedControlColor],
	// but other colors give a good baseline. For many, a gradient is involved; the
	// palette chosen based on the enum value given by +[NSColor currentColorTint].
	// Apple's documentation also suggests to use NSColorList, but the system color
	// list is just populated with class methods on NSColor.
	SkColor NSSystemColorToSkColor(NSColor* color) {
	// System colors use the an NSNamedColorSpace called "System", so first step
	// is to convert the color into something that can be worked with.
	NSColor* device_color =
	[color colorUsingColorSpace:[NSColorSpace deviceRGBColorSpace]];
	if (device_color)
	return skia::NSDeviceColorToSkColor(device_color);

	// Sometimes the conversion is not possible, but we can get an approximation
	// by going through a CGColorRef. Note that simply using NSColor methods for
	// accessing components for system colors results in exceptions like
	// "-numberOfComponents not valid for the NSColor NSNamedColorSpace System
	// windowBackgroundColor; need to first convert colorspace." Hence the
	// conversion first to CGColor.
	CGColorRef cg_color = [color CGColor];
	const size_t component_count = CGColorGetNumberOfComponents(cg_color);
	if (component_count == 4)
	return skia::CGColorRefToSkColor(cg_color);

	CHECK(component_count == 1 \|\| component_count == 2);
	// 1-2 components means a grayscale channel and maybe an alpha channel, which
	// CGColorRefToSkColor will not like. But RGB is additive, so the conversion
	// is easy (RGB to grayscale is less easy).
	const CGFloat* components = CGColorGetComponents(cg_color);
	CGFloat alpha = component_count == 2 ? components[1] : 1.0;
	return SkColorSetARGB(SkScalarRoundToInt(255.0 * alpha),
	SkScalarRoundToInt(255.0 * components[0]),
	SkScalarRoundToInt(255.0 * components[0]),
	SkScalarRoundToInt(255.0 * components[0]));
	}

	// Converts an SkColor to grayscale by using luminance for all three components.
	// Experimentally, this seems to produce a better result than a flat average or
	// a min/max average for UI controls.
	SkColor ColorToGrayscale(SkColor color) {
	SkScalar luminance = SkColorGetR(color) * 0.21 +
	SkColorGetG(color) * 0.72 +
	SkColorGetB(color) * 0.07;
	uint8_t component = SkScalarRoundToInt(luminance);
	return SkColorSetARGB(SkColorGetA(color), component, component, component);
	}

	} // namespace

	namespace ui {

	// static
	NativeTheme* NativeTheme::GetInstanceForWeb() {
	if (features::IsFormControlsRefreshEnabled())
	return NativeThemeAura::web_instance();
	return NativeThemeMac::instance();
	}

	// static
	NativeTheme* NativeTheme::GetInstanceForNativeUi() {
	return NativeThemeMac::instance();
	}

	NativeTheme* NativeTheme::GetInstanceForDarkUI() {
	static base::NoDestructor<NativeThemeMac> s_native_theme(false, true);
	return s_native_theme.get();
	}

	// static
	bool NativeTheme::SystemDarkModeSupported() {
	if (@available(macOS 10.14, *)) {
	return true;
	}
	return false;
	}

	// static
	NativeThemeMac* NativeThemeMac::instance() {
	static base::NoDestructor<NativeThemeMac> s_native_theme(true, false);
	return s_native_theme.get();
	}

	// static
	SkColor NativeThemeMac::ApplySystemControlTint(SkColor color) {
	if ([NSColor currentControlTint] == NSGraphiteControlTint)
	return ColorToGrayscale(color);
	return color;
	}

	SkColor NativeThemeMac::GetSystemColor(ColorId color_id,
	ColorScheme color_scheme) const {
	if (color_scheme == ColorScheme::kDefault)
	color_scheme = GetDefaultSystemColorScheme();

	if ((color_scheme == ColorScheme::kDark) != IsDarkMode())
	return NativeTheme::GetSystemColor(color_id, color_scheme);

	// Empirically, currentAppearance is incorrect when switching
	// appearances. It's unclear exactly why right now, so work
	// around it for the time being by resynchronizing.
	if (@available(macOS 10.14, *)) {
	NSAppearance* effective_appearance = [NSApp effectiveAppearance];
	if (![effective_appearance isEqual:[NSAppearance currentAppearance]]) {
	[NSAppearance setCurrentAppearance:effective_appearance];
	}
	}

	if (UsesHighContrastColors()) {
	switch (color_id) {
	case kColorId_SelectedMenuItemForegroundColor:
	return color_scheme == ColorScheme::kDark ? SK_ColorBLACK
	: SK_ColorWHITE;
	case kColorId_FocusedMenuItemBackgroundColor:
	return color_scheme == ColorScheme::kDark ? SK_ColorLTGRAY
	: SK_ColorDKGRAY;
	default:
	break;
	}
	}
	// Even with --secondary-ui-md, menus use the platform colors and styling, and
	// Mac has a couple of specific color overrides, documented below.
	switch (color_id) {
	case kColorId_EnabledMenuItemForegroundColor:
	return NSSystemColorToSkColor([NSColor controlTextColor]);
	case kColorId_DisabledMenuItemForegroundColor:
	return NSSystemColorToSkColor([NSColor disabledControlTextColor]);
	case kColorId_MenuSeparatorColor:
	return color_scheme == ColorScheme::kDark
	? SkColorSetA(gfx::kGoogleGrey800, 0xCC)
	: SkColorSetA(SK_ColorBLACK, 0x26);
	case kColorId_MenuBorderColor:
	return SkColorSetA(SK_ColorBLACK, 0x60);

	// Mac has a different "pressed button" styling because it doesn't use
	// ripples.
	case kColorId_ButtonPressedShade:
	return SkColorSetA(SK_ColorBLACK, 0x10);

	// There's a system setting General > Highlight color which sets the
	// background color for text selections. We honor that setting.
	// TODO(ellyjones): Listen for NSSystemColorsDidChangeNotification somewhere
	// and propagate it to the View hierarchy.
	case kColorId_LabelTextSelectionBackgroundFocused:
	case kColorId_TextfieldSelectionBackgroundFocused:
	return NSSystemColorToSkColor([NSColor selectedTextBackgroundColor]);

	case kColorId_FocusedBorderColor:
	return SkColorSetA(
	NSSystemColorToSkColor([NSColor keyboardFocusIndicatorColor]),
	0x66);

	case kColorId_TableBackgroundAlternate:
	if (@available(macOS 10.14, *)) {
	return NSSystemColorToSkColor(
	NSColor.alternatingContentBackgroundColors[1]);
	}
	return NSSystemColorToSkColor(
	NSColor.controlAlternatingRowBackgroundColors[1]);

	default:
	break;
	}

	return ApplySystemControlTint(
	NativeTheme::GetSystemColor(color_id, color_scheme));
	}

	void NativeThemeMac::PaintMenuPopupBackground(
	cc::PaintCanvas* canvas,
	const gfx::Size& size,
	const MenuBackgroundExtraParams& menu_background,
	ColorScheme color_scheme) const {
	cc::PaintFlags flags;
	flags.setAntiAlias(true);
	flags.setColor(GetSystemColor(kColorId_MenuBackgroundColor, color_scheme));
	const SkScalar radius = SkIntToScalar(menu_background.corner_radius);
	SkRect rect = gfx::RectToSkRect(gfx::Rect(size));
	canvas->drawRoundRect(rect, radius, radius, flags);
	}

	void NativeThemeMac::PaintMenuItemBackground(
	cc::PaintCanvas* canvas,
	State state,
	const gfx::Rect& rect,
	const MenuItemExtraParams& menu_item,
	ColorScheme color_scheme) const {
	switch (state) {
	case NativeTheme::kNormal:
	case NativeTheme::kDisabled:
	// Draw nothing over the regular background.
	break;
	case NativeTheme::kHovered:
	PaintSelectedMenuItem(canvas, rect, color_scheme);
	break;
	default:
	NOTREACHED();
	break;
	}
	}

	NativeThemeMac::NativeThemeMac(bool configure_web_instance,
	bool should_only_use_dark_colors)
	: NativeThemeBase(should_only_use_dark_colors) {
	if (!should_only_use_dark_colors)
	InitializeDarkModeStateAndObserver();

	if (!IsForcedHighContrast()) {
	set_high_contrast(IsHighContrast());
	__block auto theme = this;
	high_contrast_notification_token_ =
	[[[NSWorkspace sharedWorkspace] notificationCenter]
	addObserverForName:
	NSWorkspaceAccessibilityDisplayOptionsDidChangeNotification
	object:nil
	queue:nil
	usingBlock:^(NSNotification* notification) {
	theme->set_high_contrast(IsHighContrast());
	theme->NotifyObservers();
	}];
	}

	if (configure_web_instance)
	ConfigureWebInstance();
	}

	NativeThemeMac::~NativeThemeMac() {
	[[NSNotificationCenter defaultCenter]
	removeObserver:high_contrast_notification_token_];
	}

	void NativeThemeMac::PaintSelectedMenuItem(cc::PaintCanvas* canvas,
	const gfx::Rect& rect,
	ColorScheme color_scheme) const {
	// Draw the background.
	cc::PaintFlags flags;
	flags.setColor(
	GetSystemColor(kColorId_FocusedMenuItemBackgroundColor, color_scheme));
	canvas->drawRect(gfx::RectToSkRect(rect), flags);
	}

	void NativeThemeMac::InitializeDarkModeStateAndObserver() {
	__block auto theme = this;
	set_use_dark_colors(IsDarkMode());
	set_preferred_color_scheme(CalculatePreferredColorScheme());
	appearance_observer_.reset(
	[[NativeThemeEffectiveAppearanceObserver alloc] initWithHandler:^{
	theme->set_use_dark_colors(IsDarkMode());
	theme->set_preferred_color_scheme(CalculatePreferredColorScheme());
	theme->NotifyObservers();
	}]);
	}

	void NativeThemeMac::ConfigureWebInstance() {
	if (!features::IsFormControlsRefreshEnabled())
	return;

	// For FormControlsRefresh, NativeThemeAura is used as web instance so we need
	// to initialize its state.
	NativeTheme* web_instance = NativeTheme::GetInstanceForWeb();
	web_instance->set_use_dark_colors(IsDarkMode());
	web_instance->set_preferred_color_scheme(CalculatePreferredColorScheme());
	web_instance->set_high_contrast(IsHighContrast());

	// Add the web native theme as an observer to stay in sync with dark mode,
	// high contrast, and preferred color scheme changes.
	color_scheme_observer_ =
	std::make_unique<NativeTheme::ColorSchemeNativeThemeObserver>(
	NativeTheme::GetInstanceForWeb());
	AddObserver(color_scheme_observer_.get());
	}

	} // namespace ui