方法中创建的对象不可用

Question

我是第一次在学校项目中使用JavaFX，所以很可能我做了一些明显错误的事情。

在我的controller类中，我有一个方法(customerSU)，它创建了一个新的Customer和Cleast对象，我使用这些新的Customer和Cleast对象的其他方法有一个错误“无法解析符号”Cust1“。

package sample;

import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.stage.Stage;

import javax.swing.*;
import java.io.IOException;

public class Controller {

 @FXML
 Button btn1Home, btn2Home, btn1SHome, btn1THome, btnStudentSU, btn1SHHome, btnBookLesson, btnAttendLesson, btnCancelLessons;

public void homeToSHome() throws IOException {
    Parent root = FXMLLoader.load(getClass().getResource("StudentSignIn.fxml"));

    Stage window = (Stage) btn1Home.getScene().getWindow();
    window.setScene(new Scene(root, 600, 400));
}

 public void homeToTHome() throws IOException {
    Parent root = FXMLLoader.load(getClass().getResource("TutorSignIn.fxml"));

    Stage window = (Stage) btn2Home.getScene().getWindow();
    window.setScene(new Scene(root, 600, 400));
}

public void SHomeToHome() throws IOException {
    Parent root = FXMLLoader.load(getClass().getResource("Home.fxml"));

    Stage window = (Stage) btn1SHome.getScene().getWindow();
    window.setScene(new Scene(root, 600, 400));
}

public void THomeToHome() throws IOException {
    Parent root = FXMLLoader.load(getClass().getResource("Home.fxml"));

    Stage window = (Stage) btn1THome.getScene().getWindow();
    window.setScene(new Scene(root, 600, 400));
}

public void SHHomeToHome()throws IOException {
    Parent root = FXMLLoader.load(getClass().getResource("Home.fxml"));

    Stage window = (Stage) btn1SHHome.getScene().getWindow();
    window.setScene(new Scene(root, 600, 400));
}

public void customerSU() throws IOException {
    Customer cust1 = new Customer(SUFirstName.getText(), SUSurname.getText(), SUEmail.getText());
    Lesson lesson1 = new Lesson();


    Parent root = FXMLLoader.load(getClass().getResource("StudentHome.fxml"));

    Stage window = (Stage) btnStudentSU.getScene().getWindow();
    window.setScene(new Scene(root, 600, 400));
}

public void bookLesson() throws IOException {
    String response;
    response = JOptionPane.showInputDialog("Please enter the name of the lesson you wish to sign up for.");

    lesson1.BookALesson(cust1, response);
}

public void attendLesson() throws  IOException {
    lesson1.attendALesson();
}

public void customerLessonDetails() throws IOException {
    lesson1.lessonDetails();
}

public void cancelLessons() throws IOException {
    lesson1.cancelLessons();
}
}

谢谢你的帮助！

Answer 1

正如我在评论中提到的，为什么这不起作用，这里有一个解决方案。在BookLesson()方法中创建一个Customer实例，以便它能够识别您创建的实例

Customer cust1 = new Customer(SUFirstName.getText(), SUSurname.getText(), SUEmail.getText());

方法

public void bookLesson() throws IOException {
        String response;
        Customer cust1 = new Customer(SUFirstName.getText(), SUSurname.getText(), SUEmail.getText());
        Lesson lesson1 = new Lesson();
        response = JOptionPane.showInputDialog("Please enter the name of the lesson you wish to sign up for.");

        lesson1.BookALesson(cust1, response);
    }