+/**
+ * @brief This signal is emitted when the visible property of this or a parent actor is changed.
+ *
+ * A callback of the following type may be connected:
+ * @code
+ * void YourCallbackName( Actor actor, bool visible, VisibilityChange::Type& type );
+ * @endcode
+ * actor: The actor, or child of actor, whose visibility has changed
+ * visible: Whether the actor is now visible or not
+ * type: Whether the actor's visible property has changed or a parent's.
+ * @return The signal to connect to
+ * @pre The Actor has been initialized.
+ * @note This signal is NOT emitted if the actor becomes transparent (or the reverse), it's only linked with Actor::Property::VISIBLE.
+ */
+DALI_IMPORT_API VisibilityChangedSignalType& VisibilityChangedSignal( Actor actor );
+
+/**
+ * @brief This signal is emitted when the layout direction property of this or a parent actor is changed.
+ *
+ * A callback of the following type may be connected:
+ * @code
+ * void YourCallbackName( Actor actor, LayoutDirection::Type type );
+ * @endcode
+ * actor: The actor, or child of actor, whose laytou direction has changed
+ * type: Whether the actor's layout direction property has changed or a parent's.
+ * @return The signal to connect to
+ * @pre The Actor has been initialized.
+ */
+DALI_IMPORT_API LayoutDirectionChangedSignalType& LayoutDirectionChangedSignal( Actor actor );
+