如何从JavaFX中的其他类调用start方法？

Question

如何从JavaFX中的其他类调用 start 方法？我以这种方式尝试过，但没有成功！顺便说一下，我是JavaFX的新手。

        public class LoginWindow extends Application {

        private Stage window ;

        public static void main(String[] args) {
            launch(args);
        }

        @Override
        public void start(Stage primaryStage) {
            window = primaryStage ;
            window.setTitle("Login");
            GridPane grid = new GridPane() ;
            grid.setPadding(new Insets(10 , 10 ,10 ,10));
            grid.setAlignment(Pos.CENTER);
            grid.setVgap(8);
            grid.setHgap(10);

            Label usernameL = new Label("Username : ") ;
            GridPane.setConstraints(usernameL , 0 , 0);

            Label passwordL = new Label("Password : ") ;
            GridPane.setConstraints(passwordL,0 ,2 );

            TextField username = new TextField() ;
            username.setPromptText("username"); ;
            GridPane.setConstraints(username , 1 , 0);

            TextField password = new TextField() ;
            password.setPromptText("password");
            GridPane.setConstraints(password,1,2); ;

            Button login = new Button("Login") ;
            GridPane.setConstraints(login , 1 , 3);

            login.setOnAction(e -> {
                HomeWindow homeW = new HomeWindow();
                homeW.start(HomeWindow.stage);
                window.close();
            });

            grid.getChildren().addAll(usernameL,passwordL,username,password,login);

            Scene s1 = new Scene(grid,1200,800) ;
            window.setScene(s1);
            window.show();
       }
  }

那是另一类：

public class HomeWindow extends Application {
    public static Stage stage ;

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) {
        stage = primaryStage ;
        stage.setTitle("Home");
        stage.setMaximized(true);

        Label welcome = new Label("You logged sucessefully ") ;
        StackPane layout = new StackPane() ;
        layout.getChildren().add(welcome) ;
        welcome.setAlignment(Pos.CENTER);

        Scene sc = new Scene(layout) ;
        stage.setScene(sc);
        stage.show();
    }
 }

有关其他任何详细信息，请随时问我！

由于没有添加太多细节而无法发布我的问题，因此我被迫写下这些句子：（