Added system default theme mode on linux

fix brave/brave-browser#14685

Author: simonhong

browser/themes/brave_dark_mode_utils.cc

@@ -99,7 +99,11 @@ bool SystemDarkModeEnabled() {
   if (g_is_test_)
     return g_system_dark_mode_enabled_in_test_;
 
+#if BUILDFLAG(IS_LINUX)
+  return HasCachedSystemDarkModeType();
+#else
   return ui::NativeTheme::GetInstanceForNativeUi()->SystemDarkModeSupported();
+#endif
 }
 
 void SetUseSystemDarkModeEnabledForTest(bool enabled) {

browser/themes/brave_dark_mode_utils.h

@@ -57,6 +57,13 @@ void SetUseSystemDarkModeEnabledForTest(bool enabled);
 // By overriding, base ui components also use same brave theme type.
 void SetSystemDarkMode(BraveDarkModeType type);
 
+#if BUILDFLAG(IS_LINUX)
+// Cache system preference from DarkModeManagerLinux.
+// This cached value is used whenever user chooses "Same as Linux" option.
+void CacheSystemDarkModePrefs(bool prefer_dark_theme);
+bool HasCachedSystemDarkModeType();
+#endif
+
 }  // namespace dark_mode
 
 #endif  // BRAVE_BROWSER_THEMES_BRAVE_DARK_MODE_UTILS_H_

browser/themes/brave_dark_mode_utils_linux.cc

@@ -5,17 +5,31 @@
 
 #include "brave/browser/themes/brave_dark_mode_utils.h"
 
-#include "base/notreached.h"
 #include "brave/browser/themes/brave_dark_mode_utils_internal.h"
+#include "ui/native_theme/native_theme.h"
 
 namespace dark_mode {
 
+namespace {
+absl::optional<bool> g_system_dark_mode_prefs;
+}  // namespace
+
+void CacheSystemDarkModePrefs(bool prefer_dark_theme) {
+  g_system_dark_mode_prefs = prefer_dark_theme;
+}
+
+bool HasCachedSystemDarkModeType() {
+  return g_system_dark_mode_prefs.has_value();
+}
+
 void SetSystemDarkMode(BraveDarkModeType type) {
   if (type == BraveDarkModeType::BRAVE_DARK_MODE_TYPE_DEFAULT) {
-    // Linux doesn't support system dark theme so there is no chance to set
-    // default type. Default is used for 'Same as Windows/MacOS'.
-    NOTREACHED();
+    if (g_system_dark_mode_prefs.has_value()) {
+      internal::SetSystemDarkModeForNonDefaultMode(*g_system_dark_mode_prefs);
+    }
+    return;
   }
+
   internal::SetSystemDarkModeForNonDefaultMode(
       type == BraveDarkModeType::BRAVE_DARK_MODE_TYPE_DARK);
 }

browser/ui/BUILD.gn

@@ -418,6 +418,14 @@ source_set("ui") {
       ]
     }
 
+    if (is_linux && use_dbus) {
+      sources += [
+        "views/brave_dark_mode_manager_linux.cc",
+        "views/brave_dark_mode_manager_linux.h",
+      ]
+      deps += [ "//ui/linux:linux_ui_factory" ]
+    }
+
     if (enable_sparkle) {
       sources += [
         "views/update_recommended_message_box_mac.h",

browser/ui/views/brave_dark_mode_manager_linux.cc

@@ -0,0 +1,38 @@
+/* Copyright (c) 2023 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#include "brave/browser/ui/views/brave_dark_mode_manager_linux.h"
+
+#include "brave/browser/themes/brave_dark_mode_utils.h"
+#include "ui/linux/linux_ui_factory.h"
+
+namespace ui {
+
+BraveDarkModeManagerLinux::BraveDarkModeManagerLinux()
+    : DarkModeManagerLinux() {
+  // In base class' ctor, |prefer_dark_theme_| is set by calling
+  // SetColorScheme() when ui::GetDefaultLinuxUiTheme()
+  if (ui::GetDefaultLinuxUiTheme()) {
+    dark_mode::CacheSystemDarkModePrefs(prefer_dark_theme_);
+  }
+}
+
+BraveDarkModeManagerLinux::~BraveDarkModeManagerLinux() = default;
+
+void BraveDarkModeManagerLinux::SetColorScheme(bool prefer_dark_theme,
+                                               bool from_toolkit_theme) {
+  dark_mode::CacheSystemDarkModePrefs(prefer_dark_theme);
+  if (dark_mode::GetBraveDarkModeType() ==
+      dark_mode::BraveDarkModeType::BRAVE_DARK_MODE_TYPE_DEFAULT) {
+    DarkModeManagerLinux::SetColorScheme(prefer_dark_theme, from_toolkit_theme);
+  } else {
+    // Make |prefer_dark_theme_| stores latest system theme even brave theme(
+    // dark or light) is set. If not, system theme change could not be applied
+    // properly later.
+    prefer_dark_theme_ = prefer_dark_theme;
+  }
+}
+
+}  // namespace ui

browser/ui/views/brave_dark_mode_manager_linux.h

@@ -0,0 +1,25 @@
+/* Copyright (c) 2023 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_BROWSER_UI_VIEWS_BRAVE_DARK_MODE_MANAGER_LINUX_H_
+#define BRAVE_BROWSER_UI_VIEWS_BRAVE_DARK_MODE_MANAGER_LINUX_H_
+
+#include "chrome/browser/ui/views/dark_mode_manager_linux.h"
+
+namespace ui {
+
+class BraveDarkModeManagerLinux : public DarkModeManagerLinux {
+ public:
+  BraveDarkModeManagerLinux();
+  ~BraveDarkModeManagerLinux() override;
+
+ private:
+  // DarkModeManagerLinux overrides:
+  void SetColorScheme(bool prefer_dark_theme, bool from_toolkit_theme) override;
+};
+
+}  // namespace ui
+
+#endif  // BRAVE_BROWSER_UI_VIEWS_BRAVE_DARK_MODE_MANAGER_LINUX_H_

chromium_src/chrome/browser/ui/views/chrome_browser_main_extra_parts_views_linux.cc

@@ -6,23 +6,11 @@
 #include "chrome/browser/ui/views/chrome_browser_main_extra_parts_views_linux.h"
 
 #if defined(USE_DBUS)
+#include "brave/browser/ui/views/brave_dark_mode_manager_linux.h"
 #include "chrome/browser/ui/views/dark_mode_manager_linux.h"
 #endif
 
 #if defined(USE_DBUS)
-namespace ui {
-
-class BraveDarkModeManagerLinux {
- public:
-  BraveDarkModeManagerLinux() = default;
-  ~BraveDarkModeManagerLinux() = default;
-  BraveDarkModeManagerLinux(const BraveDarkModeManagerLinux&) = delete;
-  BraveDarkModeManagerLinux& operator=(const BraveDarkModeManagerLinux&) =
-      delete;
-};
-
-}  // namespace ui
-
 #define DarkModeManagerLinux BraveDarkModeManagerLinux
 #endif
 

chromium_src/chrome/browser/ui/views/dark_mode_manager_linux.h

@@ -0,0 +1,18 @@
+/* Copyright (c) 2023 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_CHROMIUM_SRC_CHROME_BROWSER_UI_VIEWS_DARK_MODE_MANAGER_LINUX_H_
+#define BRAVE_CHROMIUM_SRC_CHROME_BROWSER_UI_VIEWS_DARK_MODE_MANAGER_LINUX_H_
+
+#define SetColorScheme                    \
+  SetColorScheme_UnUsed() {}              \
+  friend class BraveDarkModeManagerLinux; \
+  virtual void SetColorScheme
+
+#include "src/chrome/browser/ui/views/dark_mode_manager_linux.h"  // IWYU pragma: export
+
+#undef SetColorScheme
+
+#endif  // BRAVE_CHROMIUM_SRC_CHROME_BROWSER_UI_VIEWS_DARK_MODE_MANAGER_LINUX_H_