+ *
+ * Signals
+ * | %Signal Name | Method |
+ * |-------------------------------|------------------------------------|
+ * | keyboardPreFocusChange | @ref PreFocusChangeSignal() |
+ * | keyboardFocusChanged | @ref FocusChangedSignal() |
+ * | keyboardFocusGroupChanged | @ref FocusGroupChangedSignal() |
+ * | keyboardFocusedActorAenterKey | @ref FocusedActorEnterKeySignal() |
+ * @SINCE_1_0.0