Fixing artifacts while changing system theme color on Windows.

src/app/puzzle/dialogs/configpages/puzzlepreferencesconfigurationpage.cpp

@@ -28,13 +28,15 @@
 
 #include "puzzlepreferencesconfigurationpage.h"
 #include "../../vpapplication.h"
+#include "../vganalytics/vganalytics.h"
+#include "../vmisc/theme/vtheme.h"
 #include "ui_puzzlepreferencesconfigurationpage.h"
+
 #if QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
 #include "../vmisc/backport/qoverload.h"
 #endif // QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
 
-#include "../vganalytics/vganalytics.h"
+#include <QStyleHints>
-#include "../vmisc/theme/vtheme.h"
 
 //---------------------------------------------------------------------------------------------------------------------
 PuzzlePreferencesConfigurationPage::PuzzlePreferencesConfigurationPage(QWidget *parent)
@@ -119,6 +121,23 @@ auto PuzzlePreferencesConfigurationPage::Apply() -> QStringList
     auto themeMode = static_cast<VThemeMode>(ui->comboBoxThemeMode->currentData().toInt());
     if (settings->GetThemeMode() != themeMode)
     {
+#if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
+        if (themeMode == VThemeMode::System && VTheme::NativeDarkThemeAvailable())
+        {
+            if (QGuiApplication::styleHints()->colorScheme() == Qt::ColorScheme::Dark)
+            {
+                settings->SetThemeMode(VThemeMode::Light);
+            }
+            else
+            {
+                settings->SetThemeMode(VThemeMode::Dark);
+            }
+
+            VTheme::Instance()->ResetThemeSettings();
+            QCoreApplication::processEvents();
+        }
+#endif
+
         settings->SetThemeMode(themeMode);
         VTheme::Instance()->ResetThemeSettings();
     }

src/app/tape/dialogs/configpages/tapepreferencesconfigurationpage.cpp

@@ -29,14 +29,17 @@
 #include "tapepreferencesconfigurationpage.h"
 #include "../../mapplication.h"
 #include "../../vtapesettings.h"
-#include "../vpatterndb/pmsystems.h"
-#include "ui_tapepreferencesconfigurationpage.h"
-#if QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
-#include "../vmisc/backport/qoverload.h"
-#endif // QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
 #include "../qmuparser/qmudef.h"
 #include "../vganalytics/vganalytics.h"
 #include "../vmisc/theme/vtheme.h"
+#include "../vpatterndb/pmsystems.h"
+#include "ui_tapepreferencesconfigurationpage.h"
+
+#if QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
+#include "../vmisc/backport/qoverload.h"
+#endif // QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
+
+#include <QStyleHints>
 
 //---------------------------------------------------------------------------------------------------------------------
 TapePreferencesConfigurationPage::TapePreferencesConfigurationPage(QWidget *parent)
@@ -122,6 +125,23 @@ auto TapePreferencesConfigurationPage::Apply() -> QStringList
     auto themeMode = static_cast<VThemeMode>(ui->comboBoxThemeMode->currentData().toInt());
     if (settings->GetThemeMode() != themeMode)
     {
+#if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
+        if (themeMode == VThemeMode::System && VTheme::NativeDarkThemeAvailable())
+        {
+            if (QGuiApplication::styleHints()->colorScheme() == Qt::ColorScheme::Dark)
+            {
+                settings->SetThemeMode(VThemeMode::Light);
+            }
+            else
+            {
+                settings->SetThemeMode(VThemeMode::Dark);
+            }
+
+            VTheme::Instance()->ResetThemeSettings();
+            QCoreApplication::processEvents();
+        }
+#endif
+
         settings->SetThemeMode(themeMode);
         VTheme::Instance()->ResetThemeSettings();
     }

src/app/valentina/dialogs/configpages/preferencesconfigurationpage.cpp

@@ -28,20 +28,22 @@
 
 #include "preferencesconfigurationpage.h"
 #include "../../core/vapplication.h"
+#include "../qmuparser/qmudef.h"
+#include "../vganalytics/vganalytics.h"
 #include "../vmisc/literals.h"
+#include "../vmisc/theme/vtheme.h"
 #include "../vmisc/vvalentinasettings.h"
 #include "../vpatterndb/pmsystems.h"
-#include "theme/vtheme.h"
 #include "ui_preferencesconfigurationpage.h"
 #include "vcommonsettings.h"
+
 #if QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
 #include "../vmisc/backport/qoverload.h"
 #endif // QT_VERSION < QT_VERSION_CHECK(5, 7, 0)
-#include "../qmuparser/qmudef.h"
-#include "../vganalytics/vganalytics.h"
 
 #include <QDir>
 #include <QDirIterator>
+#include <QStyleHints>
 #include <QTimer>
 
 //---------------------------------------------------------------------------------------------------------------------
@@ -197,6 +199,23 @@ auto PreferencesConfigurationPage::Apply() -> QStringList
     auto themeMode = static_cast<VThemeMode>(ui->comboBoxThemeMode->currentData().toInt());
     if (settings->GetThemeMode() != themeMode)
     {
+#if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
+        if (themeMode == VThemeMode::System && VTheme::NativeDarkThemeAvailable())
+        {
+            if (QGuiApplication::styleHints()->colorScheme() == Qt::ColorScheme::Dark)
+            {
+                settings->SetThemeMode(VThemeMode::Light);
+            }
+            else
+            {
+                settings->SetThemeMode(VThemeMode::Dark);
+            }
+
+            VTheme::Instance()->ResetThemeSettings();
+            QCoreApplication::processEvents();
+        }
+#endif
+
         settings->SetThemeMode(themeMode);
         VTheme::Instance()->ResetThemeSettings();
     }

src/libs/vmisc/theme/vtheme.cpp

@@ -280,11 +280,20 @@ auto VTheme::IsInDarkTheme() -> bool
 {
     if (NativeDarkThemeAvailable())
     {
+#if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
+        QStyleHints *hints = QGuiApplication::styleHints();
+        return hints->colorScheme() == Qt::ColorScheme::Dark;
+#else
 #if defined(Q_OS_MACX)
         return NSMacIsInDarkTheme();
-#else
+#elif defined(Q_OS_WIN)
+        QSettings settings("HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Themes\\Personalize",
+                           QSettings::NativeFormat);
+        return settings.value("AppsUseLightTheme", 1).toInt() == 0;
+#elif defined(Q_OS_LINUX)
         return ShouldApplyDarkTheme();
 #endif
+#endif // QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
     }
 
     return false;
@@ -353,11 +362,8 @@ void VTheme::InitApplicationStyle()
         QStyle *style = QStyleFactory::create(QStringLiteral("fusion"));
         if (style != nullptr)
         {
-            // NOLINTNEXTLINE(cppcoreguidelines-pro-type-static-cast-downcast)
-            Instance()->SetDefaultApplicationStyle(qApp->style());
             style = new VApplicationStyle(style);
-            // NOLINTNEXTLINE(cppcoreguidelines-pro-type-static-cast-downcast)
+            QApplication::setStyle(style);
-            qApp->setStyle(style);
         }
 
         return;
@@ -369,14 +375,7 @@ void VTheme::InitApplicationStyle()
     {
         if (QGuiApplication::styleHints()->colorScheme() == Qt::ColorScheme::Dark)
         {
-            QStyle *style = QStyleFactory::create(QStringLiteral("fusion"));
+            QApplication::setStyle(QStyleFactory::create(QStringLiteral("fusion")));
-            if (style != nullptr)
-            {
-                // NOLINTNEXTLINE(cppcoreguidelines-pro-type-static-cast-downcast)
-                Instance()->SetDefaultApplicationStyle(qApp->style());
-                // NOLINTNEXTLINE(cppcoreguidelines-pro-type-static-cast-downcast)
-                qApp->setStyle(style);
-            }
         }
     }
 #endif
@@ -538,9 +537,8 @@ auto VTheme::ThemeStylesheet() -> QString
 //---------------------------------------------------------------------------------------------------------------------
 void VTheme::ResetThemeSettings() const
 {
-    qApp->setStyle(Instance()->GetDefaultApplicationStyle());
-    SetToAutoTheme();
     InitApplicationStyle();
+    SetToAutoTheme();
     SetIconTheme();
     InitThemeMode();
     VSceneStylesheet::ResetStyles();
@@ -597,7 +595,29 @@ VTheme::VTheme(QObject *parent)
 {
 #if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
     QStyleHints *hints = QGuiApplication::styleHints();
-    connect(hints, &QStyleHints::colorSchemeChanged, this, []() { VTheme::Instance()->ResetThemeSettings(); });
+    connect(hints, &QStyleHints::colorSchemeChanged, this,
+            [this]()
+            {
+                VCommonSettings *settings = VAbstractApplication::VApp()->Settings();
+                VThemeMode themeMode = settings->GetThemeMode();
+                if (themeMode == VThemeMode::System && VTheme::NativeDarkThemeAvailable())
+                {
+                    if (QGuiApplication::styleHints()->colorScheme() == Qt::ColorScheme::Dark)
+                    {
+                        settings->SetThemeMode(VThemeMode::Light);
+                    }
+                    else
+                    {
+                        settings->SetThemeMode(VThemeMode::Dark);
+                    }
+
+                    ResetThemeSettings();
+                    QCoreApplication::processEvents();
+                    settings->SetThemeMode(themeMode);
+                }
+
+                ResetThemeSettings();
+            });
 #else
     if (VTheme::NativeDarkThemeAvailable())
     {
@@ -611,33 +631,10 @@ VTheme::VTheme(QObject *parent)
                     if (m_darkTheme != darkTheme)
                     {
                         m_darkTheme = darkTheme;
-                        VTheme::Instance()->ResetThemeSettings();
+                        ResetThemeSettings();
                     }
                 });
         m_themeTimer->start(V_SECONDS(5));
     }
-#endif
+#endif // QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
-}
-
-//---------------------------------------------------------------------------------------------------------------------
-auto VTheme::GetDefaultApplicationStyle() const -> QStyle *
-{
-    return m_defaultApplicationStyle;
-}
-
-//---------------------------------------------------------------------------------------------------------------------
-void VTheme::SetDefaultApplicationStyle(QStyle *defaultApplicationStyle)
-{
-    QStyle *old = m_defaultApplicationStyle;
-
-    m_defaultApplicationStyle = defaultApplicationStyle;
-    if (m_defaultApplicationStyle)
-    {
-        m_defaultApplicationStyle->setParent(this);
-    }
-
-    if (old && old->parent() == this)
-    {
-        delete old;
-    }
 }

src/libs/vmisc/theme/vtheme.h

@@ -82,14 +82,10 @@ private:
     explicit VTheme(QObject *parent = nullptr);
 
     QString m_defaultThemeName{};
-    QStyle *m_defaultApplicationStyle{nullptr};
 #if QT_VERSION < QT_VERSION_CHECK(6, 5, 0)
     QTimer *m_themeTimer{nullptr};
     bool m_darkTheme{false};
 #endif
-
-    auto GetDefaultApplicationStyle() const -> QStyle *;
-    void SetDefaultApplicationStyle(QStyle *defaultApplicationStyle);
 };
 
 #endif // VTHEME_H