Question

这是我创建登录对话框的代码，但是我想在Enter键上自动登录，而这个代码没有完成。我试过getRootPane().setDefaultButton(..);，但我没有JButton对象。

      String _options = {"ok", "Exit"};

      JOptionPane pane = new JOptionPane(this, JOptionPane.PLAIN_MESSAGE, JOptionPane.DEFAULT_OPTION, null, _options,  null);
      JDialog dialog = pane.createDialog("Login");
      dialog.setAlwaysOnTop(true);
      dialog.setVisible(true);
      dialog.requestFocus();
      dialog.toFront();

我正在考虑设置默认按钮，但有没有办法从JOptionpane获取JButton对象？

其次我们可以设置

      JOptionPane pane = new JOptionPane(this, JOptionPane.PLAIN_MESSAGE, JOptionPane.DEFAULT_OPTION, null, _options,  _options[0]); //set to _options[0]

但问题是它将焦点转移到“确定”按钮并且名称不可调焦？怎么能解决这个问题？

Answer 1

您可以创建自己的JDialog并在ActionListener字段中添加JPassword。

这是一个简单的例子。

import java.awt.*;
import java.awt.event.*;
import java.util.Arrays;
import javax.swing.*;
import javax.swing.border.EmptyBorder;

public class Password {

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable(){
            public void run() {
                new PasswordDialog();
            }
        });
    }

    static class PasswordDialog extends JDialog {
        public PasswordDialog() {
            final JLabel label = new JLabel("Type: stackoverflow");
            final JPasswordField field = new JPasswordField(20);
            final JLabel status = new JLabel("  ");

            status.setForeground(Color.RED);

            JPanel panel = new JPanel(new BorderLayout());
            panel.setBorder(new EmptyBorder(10, 10, 10, 10));
            panel.add(label, BorderLayout.NORTH);
            panel.add(field, BorderLayout.CENTER);
            panel.add(status, BorderLayout.SOUTH);

            field.addActionListener(new ActionListener(){
                public void actionPerformed(ActionEvent e) {
                    if (Arrays.equals(field.getPassword(), "stackoverflow".toCharArray())) {
                        JOptionPane.showMessageDialog(PasswordDialog.this, "Correct Password");
                    } else {
                        status.setText("Invalid Password");
                    }
                }
            });

            add(panel);
            pack();
            setLocationRelativeTo(null);
            setVisible(true);

            addWindowListener(new WindowAdapter(){
                public void windowClosing(WindowEvent e) {
                    System.exit(0);
                }
            }); 
        }
    }
}

JOptionPane将默认按钮设置为Enter键

1 个答案: