1 files changed, 39 insertions, 1 deletions

diff --git a/src/quick/items/qquickwindow.cpp b/src/quick/items/qquickwindow.cpp
index a483020439..15ade6767c 100644
--- a/src/quick/items/qquickwindow.cpp
+++ b/src/quick/items/qquickwindow.cpp
@@ -77,6 +77,9 @@
 # include <private/qopenglvertexarrayobject_p.h>
 # include <private/qsgdefaultrendercontext_p.h>
 #endif
+#ifndef QT_NO_DEBUG_STREAM
+#include <private/qdebug_p.h>
+#endif
 
 QT_BEGIN_NAMESPACE
 
@@ -87,6 +90,7 @@ Q_LOGGING_CATEGORY(DBG_MOUSE_TARGET, "qt.quick.mouse.target")
 Q_LOGGING_CATEGORY(DBG_HOVER_TRACE, "qt.quick.hover.trace")
 Q_LOGGING_CATEGORY(DBG_FOCUS, "qt.quick.focus")
 Q_LOGGING_CATEGORY(DBG_DIRTY, "qt.quick.dirty")
+Q_LOGGING_CATEGORY(lcTransient, "qt.quick.window.transient")
 
 extern Q_GUI_EXPORT QImage qt_gl_read_framebuffer(const QSize &size, bool alpha_format, bool include_alpha);
 
@@ -2738,8 +2742,10 @@ void QQuickWindowPrivate::data_append(QQmlListProperty<QObject> *property, QObje
     if (!o)
         return;
     QQuickWindow *that = static_cast<QQuickWindow *>(property->object);
-    if (QQuickWindow *window = qmlobject_cast<QQuickWindow *>(o))
+    if (QQuickWindow *window = qmlobject_cast<QQuickWindow *>(o)) {
+        qCDebug(lcTransient) << window << "is transient for" << that;
         window->setTransientParent(that);
+    }
     QQmlListProperty<QObject> itemProperty = QQuickItemPrivate::get(that->contentItem())->data();
     itemProperty.append(&itemProperty, o);
 }
@@ -3266,6 +3272,7 @@ void QQuickWindow::cleanupSceneGraph()
 
 void QQuickWindow::setTransientParent_helper(QQuickWindow *window)
 {
+    qCDebug(lcTransient) << this << "is transient for" << window;
     setTransientParent(window);
     disconnect(sender(), SIGNAL(windowChanged(QQuickWindow*)),
                this, SLOT(setTransientParent_helper(QQuickWindow*)));
@@ -4658,6 +4665,37 @@ QSGNinePatchNode *QQuickWindow::createNinePatchNode() const
     return isSceneGraphInitialized() ? d->context->sceneGraphContext()->createNinePatchNode() : nullptr;
 }
 
+#ifndef QT_NO_DEBUG_STREAM
+QDebug operator<<(QDebug debug, const QQuickWindow *win)
+{
+    QDebugStateSaver saver(debug);
+    debug.nospace();
+    if (!win) {
+        debug << "QQuickWindow(0)";
+        return debug;
+    }
+
+    debug << win->metaObject()->className() << '(' << static_cast<const void *>(win);
+    if (win->isActive())
+        debug << " active";
+    if (win->isExposed())
+        debug << " exposed";
+    debug << ", visibility=" << win->visibility() << ", flags=" << win->flags();
+    if (!win->title().isEmpty())
+        debug << ", title=" << win->title();
+    if (!win->objectName().isEmpty())
+        debug << ", name=" << win->objectName();
+    if (win->parent())
+        debug << ", parent=" << static_cast<const void *>(win->parent());
+    if (win->transientParent())
+        debug << ", transientParent=" << static_cast<const void *>(win->transientParent());
+    debug << ", geometry=";
+    QtDebugUtils::formatQRect(debug, win->geometry());
+    debug << ')';
+    return debug;
+}
+#endif
+
 #include "moc_qquickwindow.cpp"
 
 QT_END_NAMESPACE