java - 系统退出而不是JFrame关闭

Question

private void close () {

WindowEvent winClosing;
winClosing = new WindowEvent(this,WindowEvent.WINDOW_CLOSING);
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(winClosing); 
}

我试图在上面提到的关闭功能的帮助下关闭以前的 Jframe，方法是将这段代码放在附图中突出显示的后退按钮中

    this.close();
    MainMenu obj = new MainMenu();
    obj.setVisible(true);

问题是上面的代码关闭了我的整个应用程序，而不是关闭现在激活的框架

Answer 1

这是您正在尝试做的(我认为的)快速演示。
请注意:
a.我认为这不是实现此功能的正确方法。考虑使用JDialog或辅助窗口的内部框架。
b.将其视为 MCVE 的示例。事实上，使用一个辅助框架而不是两个辅助框架来演示该问题要好得多。

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.JButton;
import javax.swing.JFrame;

public class MainWindow extends JFrame  {

    private JFrame frame1, frame2;

    public MainWindow() {

        super("Main");

        //make 2 other frames
        frame1 = new Frame1(this);
        frame2 = new Frame2(this);

        setSize(400, 300);

        //add listener to quit if when window closes
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent arg0) {

                System.exit(0);
            }
        });

        //add buttn top open one frame
        JButton btnFrame1 = new JButton("Frame 1");
        btnFrame1.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent arg0) {

                //make frame 1 visible
                frame1.setVisible(true);
                //make this invisible
                setVisible(false);
            }
        });
        getContentPane().add(btnFrame1, BorderLayout.NORTH);

        //add button to open a second frame
        JButton btnFrame2 = new JButton("Frame 2");
        btnFrame2.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {

                //make frame 1 visible
                frame2.setVisible(true);
                //make this invisible
                setVisible(false);
            }
        });
        getContentPane().add(btnFrame2, BorderLayout.SOUTH);

        //make main frame visible
        setVisible(true);
    }

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

    public void showMain() {

        //make this one invisible
        frame1.setVisible(false);
        frame2.setVisible(false);

        //make main window visible
        setVisible(true);
    }
}


class Frame1 extends JFrame  {

    public Frame1(MainWindow mainWindow) {

        super("Frame 1");
        setSize(300, 200);

        //add listener to show main this window closes
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent arg0) {

                mainWindow.showMain();
            }
        });

        //add btn to hide this window and show main
        JButton btnFrame1 = new JButton("Back");
        btnFrame1.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {

                mainWindow.showMain();
            }
        });
        getContentPane().add(btnFrame1, BorderLayout.SOUTH);
        getContentPane().setBackground(Color.CYAN);

        //make it invisible
        setVisible(false);
    }
}

class Frame2 extends JFrame  {

    public Frame2(MainWindow mainWindow) {

        super("Frame 2");
        setSize(300, 200);

        //add listener to show main this window closes
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent arg0) {

                mainWindow.showMain();
            }
        });
        JButton btnFrame1 = new JButton("Back");
        btnFrame1.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {

                mainWindow.showMain();
            }
        });

        //add btn to hide this window and show main
        JButton btnMain = new JButton("Back");
        btnMain.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {

                mainWindow.showMain();
            }
        });
        getContentPane().add(btnMain, BorderLayout.SOUTH);
        getContentPane().setBackground(Color.YELLOW);

        //make it invisible
        setVisible(false);
    }
}

如有需要，请随时要求澄清。