使用scenebuilder的JavaFX11编程多个窗口

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;

public class Main extends Application {
    @Override
    public void start(Stage primaryStage) throws Exception {
        // 加载FXML文件
        Parent root = FXMLLoader.load(getClass().getResource("main.fxml"));
        
        // 创建场景
        Scene scene = new Scene(root, 800, 600);
        
        // 设置场景并显示主舞台
        primaryStage.setScene(scene);
        primaryStage.show();
    }
    
    public static void main(String[] args) {
        launch(args);
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.layout.VBox?>

<VBox xmlns="http://javafx.com/javafx/11.0.1" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.Controller">
    <Button text="打开新窗口" onAction="#openNewWindow"/>
</VBox>

import javafx.fxml.FXML;
import javafx.scene.control.Alert;
import javafx.stage.Stage;

public class Controller {
    @FXML
    private Stage primaryStage;
    
    @FXML
    private void openNewWindow() {
        try {
            // 加载新的FXML文件
            Parent root = FXMLLoader.load(getClass().getResource("newWindow.fxml"));
            
            // 创建新窗口
            Stage newStage = new Stage();
            newStage.setScene(new Scene(root, 400, 300));
            
            // 显示新窗口
            newStage.show();
        } catch (Exception e) {
            e.printStackTrace();
            showAlert("打开新窗口失败！");
        }
    }
    
    private void showAlert(String message) {
        Alert alert = new Alert(Alert.AlertType.ERROR);
        alert.setTitle("错误");
        alert.setHeaderText(null);
        alert.setContentText(message);
        alert.showAndWait();
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.AnchorPane?>

<AnchorPane xmlns="http://javafx.com/javafx/11.0.1" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.NewWindowController">
    <Label text="这是一个新窗口！"/>
</AnchorPane>

import javafx.fxml.FXML;
import javafx.scene.control.Alert;

public class NewWindowController {
    @FXML
    private void initialize() {
        showAlert("新窗口已打开！");
    }
    
    private void showAlert(String message) {
        Alert alert = new Alert(Alert.AlertType.INFORMATION);
        alert.setTitle("提示");
        alert.setHeaderText(null);
        alert.setContentText(message);
        alert.showAndWait();
    }
}