diff --git a/src/widgets/widgets/qdockwidget.h b/src/widgets/widgets/qdockwidget.h
index 82538ff1b6..2efa1d3c2f 100644
--- a/src/widgets/widgets/qdockwidget.h
+++ b/src/widgets/widgets/qdockwidget.h
@@ -20,7 +20,7 @@ class Q_WIDGETS_EXPORT QDockWidget : public QWidget
 {
     Q_OBJECT
 
-    Q_PROPERTY(bool floating READ isFloating WRITE setFloating)
+    Q_PROPERTY(bool floating READ isFloating WRITE setFloating NOTIFY topLevelChanged)
     Q_PROPERTY(DockWidgetFeatures features READ features WRITE setFeatures NOTIFY featuresChanged)
     Q_PROPERTY(Qt::DockWidgetAreas allowedAreas READ allowedAreas
                WRITE setAllowedAreas NOTIFY allowedAreasChanged)