Ensure QWaylandWindow::transientParent has a shell surface

This may not be a perfect solution, but it's better than the current one, where
the transient parent may not have a shell surface (because the window may be
hidden or not yet initialized).

Task-number: QTBUG-63840
Change-Id: Ia5f04376d4b6d12b41ceeab5ba13cdc1b63b4e3c
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>

1 files changed, 16 insertions, 11 deletions

diff --git a/src/client/qwaylandwindow.cpp b/src/client/qwaylandwindow.cpp
index f7f296d0a..6d7c0885c 100644
--- a/src/client/qwaylandwindow.cpp
+++ b/src/client/qwaylandwindow.cpp
@@ -785,22 +785,27 @@ QWaylandAbstractDecoration *QWaylandWindow::decoration() const
     return mWindowDecoration;
 }
 
-static QWindow *topLevelWindow(QWindow *window)
+static QWaylandWindow *closestShellSurfaceWindow(QWindow *window)
 {
-    while (QWindow *parent = window->parent())
-        window = parent;
-    return window;
+    while (window) {
+        auto w = static_cast<QWaylandWindow *>(window->handle());
+        if (w->shellSurface())
+            return w;
+        window = window->transientParent() ? window->transientParent() : window->parent();
+    }
+    return nullptr;
 }
 
 QWaylandWindow *QWaylandWindow::transientParent() const
 {
-    // Take the top level window here, since the transient parent may be a QWidgetWindow
-    // or some other window without a shell surface, which is then not able to get mouse
-    // events.
-    if (auto transientParent = window()->transientParent())
-        return static_cast<QWaylandWindow *>(topLevelWindow(transientParent)->handle());
-    else if (QGuiApplication::focusWindow() && (window()->type() == Qt::ToolTip || window()->type() == Qt::Popup))
-        return static_cast<QWaylandWindow *>(topLevelWindow(QGuiApplication::focusWindow())->handle());
+    // Take the closest window with a shell surface, since the transient parent may be a
+    // QWidgetWindow or some other window without a shell surface, which is then not able to
+    // get mouse events.
+    if (auto transientParent = closestShellSurfaceWindow(window()->transientParent()))
+        return transientParent;
+
+    if (QGuiApplication::focusWindow() && (window()->type() == Qt::ToolTip || window()->type() == Qt::Popup))
+        return closestShellSurfaceWindow(QGuiApplication::focusWindow());
 
     return nullptr;
 }