8 files changed, 74 insertions, 9 deletions
diff --git a/src/gui/platform/unix/dbusmenu/qdbusmenubar.cpp b/src/gui/platform/unix/dbusmenu/qdbusmenubar.cpp
index 2c006366cb4..862b60f12d0 100644
--- a/src/gui/platform/unix/dbusmenu/qdbusmenubar.cpp
+++ b/src/gui/platform/unix/dbusmenu/qdbusmenubar.cpp
@@ -4,6 +4,10 @@
 #include "qdbusmenubar_p.h"
 #include "qdbusmenuregistrarproxy_p.h"
 
+#include <private/qguiapplication_p.h>
+#include <private/qgenericunixservices_p.h>
+#include <qpa/qplatformintegration.h>
+
 QT_BEGIN_NAMESPACE
 
 using namespace Qt::StringLiterals;
@@ -18,7 +22,6 @@ QDBusMenuBar::QDBusMenuBar()
     : QPlatformMenuBar()
     , m_menu(new QDBusPlatformMenu())
     , m_menuAdaptor(new QDBusMenuAdaptor(m_menu))
-    , m_windowId(0)
 {
     QDBusMenuItem::registerDBusTypes();
     connect(m_menu, &QDBusPlatformMenu::propertiesUpdated,
@@ -88,7 +91,7 @@ void QDBusMenuBar::handleReparent(QWindow *newParentWindow)
 {
     if (newParentWindow) {
         unregisterMenuBar();
-        m_windowId = newParentWindow->winId();
+        m_window = newParentWindow;
         registerMenuBar();
     }
 }
@@ -116,30 +119,39 @@ void QDBusMenuBar::registerMenuBar()
         return;
 
     QDBusMenuRegistrarInterface registrar(REGISTRAR_SERVICE, REGISTRAR_PATH, connection, this);
-    QDBusPendingReply<> r = registrar.RegisterWindow(m_windowId, QDBusObjectPath(m_objectPath));
+    QDBusPendingReply<> r = registrar.RegisterWindow(m_window->winId(), QDBusObjectPath(m_objectPath));
     r.waitForFinished();
     if (r.isError()) {
         qWarning("Failed to register window menu, reason: %s (\"%s\")",
                  qUtf8Printable(r.error().name()), qUtf8Printable(r.error().message()));
         connection.unregisterObject(m_objectPath);
+        return;
     }
+    const auto unixServices = dynamic_cast<QGenericUnixServices *>(
+            QGuiApplicationPrivate::platformIntegration()->services());
+    unixServices->registerDBusMenuForWindow(m_window, connection.baseService(), m_objectPath);
 }
 
 void QDBusMenuBar::unregisterMenuBar()
 {
     QDBusConnection connection = QDBusConnection::sessionBus();
 
-    if (m_windowId) {
+    if (m_window) {
         QDBusMenuRegistrarInterface registrar(REGISTRAR_SERVICE, REGISTRAR_PATH, connection, this);
-        QDBusPendingReply<> r = registrar.UnregisterWindow(m_windowId);
+        QDBusPendingReply<> r = registrar.UnregisterWindow(m_window->winId());
         r.waitForFinished();
         if (r.isError())
             qWarning("Failed to unregister window menu, reason: %s (\"%s\")",
                      qUtf8Printable(r.error().name()), qUtf8Printable(r.error().message()));
+
+        const auto unixServices = dynamic_cast<QGenericUnixServices *>(
+            QGuiApplicationPrivate::platformIntegration()->services());
+        unixServices->unregisterDBusMenuForWindow(m_window);
     }
 
-    if (!m_objectPath.isEmpty())
+    if (!m_objectPath.isEmpty()) {
         connection.unregisterObject(m_objectPath);
+    }
 }
 
 QT_END_NAMESPACE
diff --git a/src/gui/platform/unix/dbusmenu/qdbusmenubar_p.h b/src/gui/platform/unix/dbusmenu/qdbusmenubar_p.h
index 3028df7215d..24c63802aa1 100644
--- a/src/gui/platform/unix/dbusmenu/qdbusmenubar_p.h
+++ b/src/gui/platform/unix/dbusmenu/qdbusmenubar_p.h
@@ -42,7 +42,7 @@ private:
     QDBusPlatformMenu *m_menu;
     QDBusMenuAdaptor *m_menuAdaptor;
     QHash<quintptr, QDBusPlatformMenuItem *> m_menuItems;
-    uint m_windowId;
+    QPointer<QWindow> m_window;
     QString m_objectPath;
 
     QDBusPlatformMenuItem *menuItemForMenu(QPlatformMenu *menu);
diff --git a/src/gui/platform/unix/qgenericunixservices.cpp b/src/gui/platform/unix/qgenericunixservices.cpp
index 3aa071b8b26..32487b16511 100644
--- a/src/gui/platform/unix/qgenericunixservices.cpp
+++ b/src/gui/platform/unix/qgenericunixservices.cpp
@@ -577,6 +577,20 @@ QString QGenericUnixServices::portalWindowIdentifier(QWindow *window)
     return QString();
 }
 
+
+void QGenericUnixServices::registerDBusMenuForWindow(QWindow *window, const QString &service, const QString &path)
+{
+    Q_UNUSED(window);
+    Q_UNUSED(service);
+    Q_UNUSED(path);
+}
+
+void QGenericUnixServices::unregisterDBusMenuForWindow(QWindow *window)
+{
+    Q_UNUSED(window);
+}
+
+
 bool QGenericUnixServices::hasCapability(Capability capability) const
 {
     switch (capability) {
diff --git a/src/gui/platform/unix/qgenericunixservices_p.h b/src/gui/platform/unix/qgenericunixservices_p.h
index 8bb49527793..9e34f090229 100644
--- a/src/gui/platform/unix/qgenericunixservices_p.h
+++ b/src/gui/platform/unix/qgenericunixservices_p.h
@@ -39,6 +39,9 @@ public:
     void setApplicationBadge(qint64 number);
     virtual QString portalWindowIdentifier(QWindow *window);
 
+    virtual void registerDBusMenuForWindow(QWindow *window, const QString &service, const QString &path);
+    virtual void unregisterDBusMenuForWindow(QWindow *window);
+
 private:
     QString m_webBrowser;
     QString m_documentLauncher;
diff --git a/src/plugins/platforms/xcb/qxcbatom.cpp b/src/plugins/platforms/xcb/qxcbatom.cpp
index dd5596653cd..d31773a34db 100644
--- a/src/plugins/platforms/xcb/qxcbatom.cpp
+++ b/src/plugins/platforms/xcb/qxcbatom.cpp
@@ -204,6 +204,8 @@ static const char *xcb_atomnames = {
     "EDID_DATA\0"
     "XFree86_DDC_EDID1_RAWDATA\0"
     "_ICC_PROFILE\0"
+    "_KDE_NET_WM_APPMENU_SERVICE_NAME\0"
+    "_KDE_NET_WM_APPMENU_OBJECT_PATH\0"
     // \0\0 terminates loop.
 };
 
diff --git a/src/plugins/platforms/xcb/qxcbatom.h b/src/plugins/platforms/xcb/qxcbatom.h
index bc677eaf3e3..7dd52f122c7 100644
--- a/src/plugins/platforms/xcb/qxcbatom.h
+++ b/src/plugins/platforms/xcb/qxcbatom.h
@@ -211,6 +211,10 @@ public:
 
         Atom_ICC_PROFILE,
 
+        // AppMenu
+        Atom_KDE_NET_WM_APPMENU_SERVICE_NAME,
+        Atom_KDE_NET_WM_APPMENU_OBJECT_PATH,
+
         NAtoms
     };
 
diff --git a/src/plugins/platforms/xcb/qxcbintegration.cpp b/src/plugins/platforms/xcb/qxcbintegration.cpp
index 4dafae31e31..fc5a7e55c50 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.cpp
+++ b/src/plugins/platforms/xcb/qxcbintegration.cpp
@@ -93,10 +93,12 @@ static bool runningUnderDebugger()
 #endif
 }
 
-class QXcbUnixServices : public QGenericUnixServices
+class QXcbUnixServices : public QGenericUnixServices, public QXcbObject
 {
 public:
     QString portalWindowIdentifier(QWindow *window) override;
+    void registerDBusMenuForWindow(QWindow *window, const QString &service, const QString &path) override;
+    void unregisterDBusMenuForWindow(QWindow *window) override;
 };
 
 
@@ -173,6 +175,7 @@ QXcbIntegration::QXcbIntegration(const QStringList &parameters, int &argc, char
         m_connection = nullptr;
         return;
     }
+    m_services->setConnection(m_connection);
 
     m_fontDatabase.reset(new QGenericUnixFontDatabase());
 
@@ -601,4 +604,30 @@ QString QXcbUnixServices::portalWindowIdentifier(QWindow *window)
     return "x11:"_L1 + QString::number(window->winId(), 16);
 }
 
+void QXcbUnixServices::registerDBusMenuForWindow(QWindow *window, const QString &service, const QString &path)
+{
+    const QByteArray serviceValue = service.toLatin1();
+    const QByteArray pathValue = path.toLatin1();
+
+    xcb_change_property(xcb_connection(),
+                        XCB_PROP_MODE_REPLACE, window->winId(),
+                        atom(QXcbAtom::Atom_KDE_NET_WM_APPMENU_SERVICE_NAME),
+                        XCB_ATOM_STRING, 8,
+                        serviceValue.length(),
+                        serviceValue.constData());
+
+    xcb_change_property(xcb_connection(),
+                        XCB_PROP_MODE_REPLACE, window->winId(),
+                        atom(QXcbAtom::Atom_KDE_NET_WM_APPMENU_OBJECT_PATH),
+                        XCB_ATOM_STRING, 8,
+                        pathValue.length(),
+                        pathValue.constData());
+}
+
+void QXcbUnixServices::unregisterDBusMenuForWindow(QWindow *window)
+{
+    xcb_delete_property(xcb_connection(), window->winId(), atom(QXcbAtom::Atom_KDE_NET_WM_APPMENU_SERVICE_NAME));
+    xcb_delete_property(xcb_connection(), window->winId(), atom(QXcbAtom::Atom_KDE_NET_WM_APPMENU_OBJECT_PATH));
+}
+
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/xcb/qxcbintegration.h b/src/plugins/platforms/xcb/qxcbintegration.h
index a1e0c3f3e1b..a5323496f75 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.h
+++ b/src/plugins/platforms/xcb/qxcbintegration.h
@@ -18,6 +18,7 @@ QT_BEGIN_NAMESPACE
 class QXcbConnection;
 class QAbstractEventDispatcher;
 class QXcbNativeInterface;
+class QXcbUnixServices;
 
 class Q_XCB_EXPORT QXcbIntegration : public QPlatformIntegration
 #ifndef QT_NO_OPENGL
@@ -115,7 +116,7 @@ private:
     mutable QScopedPointer<QPlatformAccessibility> m_accessibility;
 #endif
 
-    QScopedPointer<QPlatformServices> m_services;
+    QScopedPointer<QXcbUnixServices> m_services;
 
     mutable QByteArray m_wmClass;
     const char *m_instanceName;