java - 简单的 JavaFX 浏览器仅在第一次打开时有效

Question

我有这个代码来打开自定义 Java 浏览器:

private void openNavigator(){

    Navigator browser = new Navigator();
    SwingUtilities.invokeLater(() -> {

        browser.initComponents();

        browser.setVisible(true);

        browser.loadURL("http://XXXXXXXX:8888/YYYYYY/ZZZZ");
    });
}

另一方面，我有导航器的代码:

public class Navigator extends JFrame {

    private static final Logger LOG = Logger.getLogger(Navegador.class.getName());
    private static final long serialVersionUID = -1951385676682823399L;

    private WebView view;
    private JFXPanel javaFxPanel;
    private WebEngine engine;

    private JLabel labelStatus;
    private JTextField direction;
    private JProgressBar progressBar;

    private java.net.CookieManager cookiesManager;


    public void initComponents() {

        if (cookiesManager != null) {
            cookiesManager = new java.net.CookieManager();
            java.net.CookieHandler.setDefault(cookiesManager);
        }

        javaFxPanel = new JFXPanel();
        labelStatus = new JLabel();

        JPanel panelTodo = new JPanel(new BorderLayout());
        JButton botonBuscar = new JButton("Search");
        direction = new JTextField();
        progressBar = new JProgressBar();

        createScene();

        ActionListener direcctionListener = new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                loadURL(direction.getText());
            }
        };

        botonBuscar.addActionListener(direcctionListener);
        direction.addActionListener(direcctionListener);

        progressBar.setPreferredSize(new Dimension(150, 18));
        progressBar.setStringPainted(true);

        JPanel topBar = new JPanel(new BorderLayout(5, 0));
        topBar.setBorder(BorderFactory.createEmptyBorder(3, 5, 3, 5));
        topBar.add(direction, BorderLayout.CENTER);
        topBar.add(botonBuscar, BorderLayout.EAST);

        JPanel statusBar = new JPanel(new BorderLayout(5, 0));
        statusBar.setBorder(BorderFactory.createEmptyBorder(3, 5, 3, 5));
        statusBar.add(labelStatus, BorderLayout.CENTER);
        statusBar.add(progressBar, BorderLayout.EAST);

        panelTodo.add(topBar, BorderLayout.NORTH);
        panelTodo.add(javaFxPanel, BorderLayout.CENTER);
        panelTodo.add(statusBar, BorderLayout.SOUTH);

        getContentPane().add(panelTodo);

        setPreferredSize(new Dimension(1024, 600));
        setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        pack();
    }

    private void createScene() {

        Platform.runLater(() -> {
            view = new WebView();
            engine = view.getEngine();

            engine.setOnAlert((WebEvent<String> wEvent) -> {
                System.out.println("JS alert() message: " + wEvent.getData());
            });

            engine.titleProperty().addListener(new ChangeListener<String>() {
                @Override
                public void changed(ObservableValue<? extends String> observable, String oldValue, final String newValue) {
                    SwingUtilities.invokeLater(new Runnable() {
                        @Override
                        public void run() {
                            Navegador.this.setTitle(newValue);
                        }
                    });
                }
            });

            engine.setOnStatusChanged(new EventHandler<WebEvent<String>>() {
                @Override
                public void handle(final WebEvent<String> event) {
                    SwingUtilities.invokeLater(new Runnable() {
                        @Override
                        public void run() {
                            labelStatus.setText(event.getData());
                        }
                    });
                }
            });

            engine.locationProperty().addListener(new ChangeListener<String>() {
                @Override
                public void changed(ObservableValue<? extends String> ov, String viejoValor, final String nuevoValor) {
                    SwingUtilities.invokeLater(new Runnable() {
                        @Override
                        public void run() {
                            direction.setText(nuevoValor);
                        }
                    });
                }
            });

            engine.getLoadWorker().workDoneProperty().addListener(new ChangeListener<Number>() {
                @Override
                public void changed(ObservableValue<? extends Number> observableValue, Number oldValue, final Number newValue) {
                    SwingUtilities.invokeLater(new Runnable() {
                        @Override
                        public void run() {
                            progressBar.setValue(newValue.intValue());
                        }
                    });
                }
            });

            engine.getLoadWorker().exceptionProperty()
                    .addListener(new ChangeListener<Throwable>() {

                        @Override
                        public void changed(ObservableValue<? extends Throwable> o, Throwable old, final Throwable value) {
                            if (engine.getLoadWorker().getState() == FAILED) {
                                SwingUtilities.invokeLater(new Runnable() {
                                    @Override
                                    public void run() {
                                        //TODO Handling Exception
                                    }
                                });
                            }
                        }
                    });

            javaFxPanel.setScene(new Scene(view));
        });
    }

    public void loadURL(String url) {
        Platform.runLater(new Runnable() {
            @Override
            public void run() {
                String urlTemporal = toURL(url);

                if (urlTemporal == null) {
                    urlTemporal = toURL("http://" + url);
                }

                engine.load(urlTemporal);
            }
        });
    }

    private static String toURL(String str) {
        try {
            return new URL(str).toExternalForm();
        } catch (MalformedURLException exception) {
            return null;
        }
    }

}

我的问题是，当我第一次打开导航器时它可以工作，但是当我关闭它然后再次打开时它只显示 TextField 和 Button

注释:

1. 我使用 javaswing 按钮打开导航器 openNavigator() 方法
2. 当我离开一个导航器而没有关闭时，同时我 打开一个或多个导航器，它运行良好

我第一次打开导航器:

我第二次打开导航器:

Answer 1

JavaFX 线程/工具包必须正在运行。显然，创建一个 JFXPanel 足以初始化它，但一旦关闭，线程就会自动终止。
阻止它自动关闭通话

Platform.setImplicitExit(false); 

因此，JavaFX 工具包仅在调用 Platform#exit 方法或整个应用程序终止时关闭。