Ich habe dieses undekorierte Fenster:

public static void initStartPage(final Stage primaryStage) {

        final Stage startPage = new Stage();
        startPage.initStyle(StageStyle.UNDECORATED);
        //startPage.initOwner(primaryStage);
        //startPage.toFront();
        Scene scene = new Scene(agentsPanel(), 900, 500);
        startPage.setScene(scene);
        startPage.show();

    }

Ich bin interessiert, wie ich es ziehen kann? Ich möchte, dass ich den Mauszeiger darüber ziehe, um seine Position zu ändern.

P.S

Ich habe diese Lösung getestet, aber sie funktioniert nicht:

private static FlowPane flow;
    private static BorderPane bpi;

    public static void initStartPage(final Stage primaryStage) {

        final Stage startPage = new Stage();
        startPage.initStyle(StageStyle.UNDECORATED);
        startPage.initOwner(primaryStage);
        //startPage.toFront();
        Scene scene = new Scene(agentsPanel(primaryStage), 900, 500);
        startPage.setScene(scene);
        startPage.show();

    }

    private static double xOffset = 0;
    private static double yOffset = 0;

    public static BorderPane agentsPanel(final Stage primaryStage) {

        BorderPane bp = new BorderPane();
        bp.setPrefSize(900, 500);
        bp.setMaxSize(900, 500);

        HBox thb = new HBox(10); // Set spacing between each child into the HBox
        thb.setPadding(new Insets(15, 15, 15, 15));


        HBox bhb = new HBox(10); // Set spacing between each child into the HBox
        bhb.setPadding(new Insets(15, 15, 15, 15));

        bp.setTop(thb);
        bp.setBottom(bhb);
        bp.setCenter(navigationPanel());


        bp.setOnMousePressed(new EventHandler<MouseEvent>() {
            @Override
            public void handle(MouseEvent event) {
                xOffset = event.getSceneX();
                yOffset = event.getSceneY();
            }
        });
        bp.setOnMouseDragged(new EventHandler<MouseEvent>() {
            @Override
            public void handle(MouseEvent event) {
                primaryStage.setX(event.getScreenX() - xOffset);
                primaryStage.setY(event.getScreenY() - yOffset);
            }
        });

        return bp;

    }