Windows QPA: Add detection of dark mode

Read the dark mode setting and make it accessible
via native interface.
Add a command line option to set the support level.

Task-number: QTBUG-72028
Change-Id: I1e9fe296a6b1bda81512d003183038b866b67545
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>

1 files changed, 4 insertions, 0 deletions

diff --git a/src/plugins/platforms/windows/qwindowsintegration.cpp b/src/plugins/platforms/windows/qwindowsintegration.cpp
index 32bd29a842..4b4047ac0c 100644
--- a/src/plugins/platforms/windows/qwindowsintegration.cpp
+++ b/src/plugins/platforms/windows/qwindowsintegration.cpp
@@ -219,6 +219,10 @@ static inline unsigned parseOptions(const QStringList &paramList,
             options |= QWindowsIntegration::DontUseWMPointer;
         } else if (param == u"reverse") {
             options |= QWindowsIntegration::RtlEnabled;
+        } else if (param == u"darkmode=1") {
+            options |= QWindowsIntegration::DarkModeWindowFrames;
+        } else if (param == u"darkmode=2") {
+            options |= QWindowsIntegration::DarkModeWindowFrames | QWindowsIntegration::DarkModeStyle;
         } else {
             qWarning() << "Unknown option" << param;
         }