如何在场景图的节点中监听WindowEvent.WINDOW_SHOWN？

我想其中一个可能的解决方案是添加以下方法

TestController.java

    
          public void handleWindowShownEvent()
    {
        usernameInput.requestFocus();
    }
</code>
  

    
          @Override
    public void start(Stage stage) throws Exception
    {
        FXMLLoader loader = new FXMLLoader();
        Parent root = (Parent)loader.load(TestController.class.getResourceAsStream(“TestView.fxml”));
        final TestController controller = (TestController)loader.getController();
        stage.addEventHandler(WindowEvent.WINDOW_SHOWN, new EventHandler()
        {
            @Override
            public void handle(WindowEvent window)
            {
                controller.handleWindowShownEvent();
            }
        });
        Scene scene = new Scene(root);
        stage.setScene(scene);
        stage.show();
    }
</code>
  

另一个解决方案当然不是很性感但是将节点与应用程序分离：

    
      root.sceneProperty().addListener(new ChangeListener() {
  @Override
  public void changed(ObservableValue<? extends Scene> observable, Scene oldValue, Scene newValue) {
    newValue.windowProperty().addListener(new ChangeListener() {
      @Override
      public void changed(ObservableValue<? extends Window> observable, Window oldValue, Window newValue) {
        newValue.addEventHandler(WindowEvent.WINDOW_SHOWN, new EventHandler() {
          @Override
          public void handle(WindowEvent event) {
            usernameInput.requestFocus();
          }
        });
      }
    });
  }
});
</code>