加载fxml后获取节点的子节点

import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Node;
import javafx.scene.control.Button;
import javafx.scene.layout.VBox;

public class Main {
    public static void main(String[] args) {
        try {
            // 加载FXML文件
            FXMLLoader loader = new FXMLLoader();
            Parent root = loader.load(Main.class.getResource("sample.fxml").openStream());

            // 获取根节点
            VBox vbox = (VBox) root;

            // 获取子节点
            ObservableList<Node> children = vbox.getChildren();
            for (Node child : children) {
                // 处理子节点
                if (child instanceof Button) {
                    Button button = (Button) child;
                    System.out.println("Button: " + button.getText());
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}