Make use of foreign protocol

Summary:
not sure if that is the right "parent" that has
to be set, set the transient for surfaces that
have setParentOf of an imported set

Test Plan:
m_XdgForeign->transientFor(surface()) finds the surface is expected,
not sure how to test it further

Reviewers: #plasma, graesslin

Reviewed By: #plasma, graesslin

Subscribers: luebking, graesslin, davidedmundson, plasma-devel, kwin, #kwin

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D7521

shell_client.cpp

@@ -315,6 +315,11 @@ void ShellClient::init()
     getShadow();
     connect(s, &SurfaceInterface::shadowChanged, this, &Toplevel::getShadow);
 
+    connect(waylandServer(), &WaylandServer::foreignTransientChanged, this, [this](KWayland::Server::SurfaceInterface *child) {
+        if (child == surface()) {
+            setTransient();
+        }
+    });
     setTransient();
     // check whether we have a ServerSideDecoration
     if (ServerSideDecorationInterface *deco = ServerSideDecorationInterface::get(s)) {
@@ -1392,6 +1397,9 @@ void ShellClient::setTransient()
     if (m_xdgShellPopup) {
         s = m_xdgShellPopup->transientFor().data();
     }
+    if (!s) {
+        s = waylandServer()->findForeignTransientForSurface(surface());
+    }
     auto t = waylandServer()->findClient(s);
     if (t != transientFor()) {
         // remove from main client

wayland_server.cpp

@@ -52,6 +52,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <KWayland/Server/outputmanagement_interface.h>
 #include <KWayland/Server/outputconfiguration_interface.h>
 #include <KWayland/Server/xdgshell_interface.h>
+#include <KWayland/Server/xdgforeign_interface.h>
 
 // Qt
 #include <QThread>
@@ -158,6 +159,11 @@ void WaylandServer::createSurface(T *surface)
     } else {
         connect(client, &ShellClient::windowShown, this, &WaylandServer::shellClientShown);
     }
+
+    //not directly connected as the connection is tied to client instead of this
+    connect(m_XdgForeign, &KWayland::Server::XdgForeignInterface::transientChanged, client, [this](KWayland::Server::SurfaceInterface *child, KWayland::Server::SurfaceInterface *parent) {
+        emit foreignTransientChanged(child);
+    });
 }
 
 bool WaylandServer::init(const QByteArray &socketName, InitalizationFlags flags)
@@ -308,9 +314,17 @@ bool WaylandServer::init(const QByteArray &socketName, InitalizationFlags flags)
 
     m_display->createSubCompositor(m_display)->create();
 
+    m_XdgForeign = m_display->createXdgForeignInterface(m_display);
+    m_XdgForeign->create();
+
     return true;
 }
 
+SurfaceInterface *WaylandServer::findForeignTransientForSurface(SurfaceInterface *surface)
+{
+    return m_XdgForeign->transientFor(surface);
+}
+
 void WaylandServer::shellClientShown(Toplevel *t)
 {
     ShellClient *c = dynamic_cast<ShellClient*>(t);

wayland_server.h

@@ -56,6 +56,7 @@ class QtSurfaceExtensionInterface;
 class OutputManagementInterface;
 class OutputConfigurationInterface;
 class XdgShellInterface;
+class XdgForeignInterface;
 }
 }
 
@@ -112,6 +113,11 @@ public:
     AbstractClient *findAbstractClient(KWayland::Server::SurfaceInterface *surface) const;
     ShellClient *findClient(QWindow *w) const;
 
+    /**
+     * return a transient parent of a surface imported with the foreign protocol, if any
+     */
+    KWayland::Server::SurfaceInterface *findForeignTransientForSurface(KWayland::Server::SurfaceInterface *surface);
+
     /**
      * @returns file descriptor for Xwayland to connect to.
      **/
@@ -189,6 +195,7 @@ Q_SIGNALS:
     void shellClientRemoved(KWin::ShellClient*);
     void terminatingInternalClientConnection();
     void initialized();
+    void foreignTransientChanged(KWayland::Server::SurfaceInterface *child);
 
 private:
     void setupX11ClipboardSync();
@@ -232,6 +239,7 @@ private:
         KWayland::Server::ClientConnection *client = nullptr;
         QPointer<KWayland::Server::DataDeviceInterface> ddi;
     } m_xclipbaordSync;
+    KWayland::Server::XdgForeignInterface *m_XdgForeign = nullptr;
     QList<ShellClient*> m_clients;
     QList<ShellClient*> m_internalClients;
     QHash<KWayland::Server::ClientConnection*, quint16> m_clientIds;