eclipse 如何在 Swing 应用程序中使用退出按钮？

How to use Exit button in Swing Application?

提问by Sondhi

I am new in Java Form Application development using Swing. What is the suitable code for exit button that will exit the application?

我是使用 Swing 进行 Java 表单应用程序开发的新手。退出应用程序的退出按钮的合适代码是什么？

For example:In C# (.NET Framework) we use Application.Exit();as the code for exit what button. What is the equivalent code in Java to exit an application?

例如：在 C# (.NET Framework) 中，我们使用Application.Exit();退出按钮的代码。Java 中退出应用程序的等效代码是什么？

回答by Andrew Thompson

jFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

Now for a bit of explanation. The closest equivalent to as seen in the question is..

现在稍微解释一下。与问题中最接近的等价物是..

jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

But that kills the entire JRE irrespective of other non-daemon threads that are running. If they are running, they should be shut down or cleaned up explicitly.

但这会杀死整个 JRE，而不管其他正在运行的非守护进程线程如何。如果它们正在运行，则应明确关闭或清理它们。

If there are no other non-daemon threads running, DISPOSE_ON_CLOSEwill dispose the current JFrameand end the virtual machine.

如果没有其他非守护线程在运行，DISPOSE_ON_CLOSE将处理当前JFrame并结束虚拟机。

回答by predi

@AndrewThompson is right about JFrame.EXIT_ON_CLOSEbut you can take steps to avoid just killing stuff.

@AndrewThompson 是对的，JFrame.EXIT_ON_CLOSE但您可以采取措施避免杀死东西。

JFrame.EXIT_ON_CLOSEis just fine, if you handle cleanup in an overridden JFrame.processWindowEvent(WindowEvent)checking for WindowEvent.WINDOW_CLOSINGevents.

JFrame.EXIT_ON_CLOSE很好，如果您在覆盖JFrame.processWindowEvent(WindowEvent)的WindowEvent.WINDOW_CLOSING事件检查中处理清理。

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowEvent;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JProgressBar;
import javax.swing.Timer;

public class ExitJFrame extends JFrame {

    public ExitJFrame() {
        setLayout(new BorderLayout());

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JButton button = new JButton("Exit");
        add(button);

        button.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                ExitJFrame.this.processWindowEvent(
                        new WindowEvent(
                                ExitJFrame.this, WindowEvent.WINDOW_CLOSING));
            }
        });

        setSize(200, 200);
        setLocationRelativeTo(null);
    }

    @Override
    protected void processWindowEvent(WindowEvent e) {
        // more powerful as a WindowListener, since you can consume the event 
        // if you so please - asking the user if she really wants to exit for
        // example, do not delegate to super if consuming.
        if (e.getID() == WindowEvent.WINDOW_CLOSING) {
            doCleanup();
            super.processWindowEvent(e); 
        } else {        
            super.processWindowEvent(e); 
        }
    }

    private void doCleanup() {
        final JDialog dialog = new JDialog(this, true);
        dialog.setLayout(new BorderLayout());
        dialog.setUndecorated(true);
        JProgressBar progress = new JProgressBar();
        dialog.add(progress);
        dialog.add(new JLabel("Waiting for non-daemon threads to exit gracefully..."), BorderLayout.NORTH);
        progress.setIndeterminate(true);

        Timer timer = new Timer(2000, new ActionListener() {

            public void actionPerformed(ActionEvent e) {
                dialog.setVisible(false);
                dialog.dispose();
            }
        });
        timer.setRepeats(false);
        timer.start();
        dialog.pack();
        dialog.setLocationRelativeTo(this);
        dialog.setVisible(true);
    }

    public static void main (String[] args) {
        new ExitJFrame().setVisible(true);
    }

}

回答by Eyadkht

If you want to create a button which exits the application when the user clicks it, try this:

如果您想创建一个在用户单击时退出应用程序的按钮，请尝试以下操作：

JButton exit = new JButton("exit");

ActionListener al = new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e) {
        System.exit(0);
    }
};

exit.addActionListener(al);

Now when you press on that button the application will exit.

现在，当您按下该按钮时，应用程序将退出。

回答by chiastic-security

If you're talking about a JButtonthat you want to put into your form, then you want to invoke JFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE)in your constructor for the form, and then your button handler can invoke

如果您正在谈论JButton要放入表单中的 a，那么您想要JFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE)在表单的构造函数中调用，然后您的按钮处理程序可以调用

dispose()

to close the form.

关闭表单。

回答by Krishna

Very simple answer is as @Andrew Thompson said.

正如@Andrew Thompson 所说，非常简单的答案。

jFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

OR

或者

jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

and if u want to make it in other way by code. then u can put this code anywhere. in events.

如果你想通过代码以其他方式制作它。然后你可以把这个代码放在任何地方。在事件中。

System.exit(0);

System.exit(0);

hope this will help.

希望这会有所帮助。