From 124e63965ee73bb620fdefe3f9d2307f1d5830c5 Mon Sep 17 00:00:00 2001
From: Wladimir Leuschner <wladimir.leuschner@qt.io>
Date: Mon, 15 Jan 2024 12:32:52 +0100
Subject: [PATCH] QWindows11Style: Fix QMessageBox drawing for light/dark mode

Fixes: QTBUG-120748
Change-Id: I4101848e2e91c489cb53b38ae6bf0171701c5c54
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
(cherry picked from commit 27dea6cf23c22c8ee2f82d97486f248559e57993)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 .../styles/modernwindows/qwindows11style.cpp      | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/plugins/styles/modernwindows/qwindows11style.cpp b/src/plugins/styles/modernwindows/qwindows11style.cpp
index d7548b6517f..bf015c53aee 100644
--- a/src/plugins/styles/modernwindows/qwindows11style.cpp
+++ b/src/plugins/styles/modernwindows/qwindows11style.cpp
@@ -765,6 +765,21 @@ void QWindows11Style::drawPrimitive(PrimitiveElement element, const QStyleOption
             }
         }
         break;
+    case QStyle::PE_Widget: {
+#if QT_CONFIG(dialogbuttonbox)
+        const QDialogButtonBox *buttonBox = nullptr;
+        if (qobject_cast<const QMessageBox *> (widget))
+            buttonBox = widget->findChild<const QDialogButtonBox *>(QLatin1String("qt_msgbox_buttonbox"));
+#if QT_CONFIG(inputdialog)
+        else if (qobject_cast<const QInputDialog *> (widget))
+            buttonBox = widget->findChild<const QDialogButtonBox *>(QLatin1String("qt_inputdlg_buttonbox"));
+#endif // QT_CONFIG(inputdialog)
+        if (buttonBox) {
+            painter->fillRect(option->rect,option->palette.window());
+        }
+#endif
+        break;
+    }
     default:
         QWindowsVistaStyle::drawPrimitive(element, option, painter, widget);
     }