Question

我制作了一个BoxLayout GUI，我想知道我是如何使用actionlistener使按钮关闭窗口的。如果我尝试输入RegisterNew.setVisible（false）;在actionlistener中，它给了我一个错误

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class RegisterNew extends JFrame
{
public RegisterNew(int axis){
    // creates the JFrame
    super("BoxLayout Demo");

    Container con = getContentPane();

    con.setLayout(new BoxLayout(con, axis));

    con.add(new JLabel("Enter your desired username"));
    con.add(new JTextField());
    con.add(new JLabel("Enter your password"));
    con.add(new JTextField());
    con.add(new JButton("Create Account"));

    setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);

    pack();

    setVisible(true);
}

public static void main(String args[])
{
    RegisterNew newDemo = new RegisterNew(BoxLayout.Y_AXIS);
}

}

我也试图将它链接到另一个GUI，这样当你按下一个按钮时，会出现这个，但它给了我同样的错误，就好像我把它放在一起 RegisterNew.setVisible（真）;进入动作监听器

Answer 1

如果那是一个从属对话窗口，那么使用JDialog，而不是JFrame。
如果您的ActionListener是内部类，则使用RegisterNew.this.close();
否则，您可以使用SwingUtilities.getWindowAncestor(button)获取JButton的窗口祖先，并在返回的窗口上调用close()或更好dispose()。
请注意，BoxLayout和布局管理器通常与您当前的问题无关。

如，

显示新注册对话框并从中提取信息的测试类。

import java.awt.BorderLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;

import javax.swing.*;

public class TestRegistration extends JPanel {
    private JTextArea textArea = new JTextArea(30, 60);

    public TestRegistration() {
        JPanel bottomPanel = new JPanel();
        bottomPanel.add(new JButton(new ShowRegisterNewAction()));
        textArea.setFocusable(false);
        textArea.setEditable(false);

        setLayout(new BorderLayout());
        add(new JScrollPane(textArea, 
                JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, 
                JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED));
        add(bottomPanel, BorderLayout.PAGE_END);
    }

    private class ShowRegisterNewAction extends AbstractAction {
        private RegisterNew registerNew = null;

        public ShowRegisterNewAction() {
            super("Show Register New Dialog");
            putValue(MNEMONIC_KEY, KeyEvent.VK_S);
        }

        @Override
        public void actionPerformed(ActionEvent e) {
            if (registerNew == null) {
                JButton btn = (JButton) e.getSource();
                Window window = SwingUtilities.getWindowAncestor(btn);
                registerNew = new RegisterNew(window, BoxLayout.PAGE_AXIS);
            }
            registerNew.setVisible(true);
            String userName = registerNew.getUserName();
            String password = new String(registerNew.getPassword());

            textArea.append("User Name: " + userName + "\n");
            textArea.append("Password: " + password + "\n");
            textArea.append("\n");
        }
    }

    private static void createAndShowGui() {
        JFrame frame = new JFrame("TestRegistration");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().add(new TestRegistration());
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> createAndShowGui());
    }
}

新的Register类，它包含对话框并具有显示它和从中提取信息的代码。使用BoxLayout。

import java.awt.Container;
import java.awt.Window;
import java.awt.Dialog.ModalityType;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;

import javax.swing.AbstractAction;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;

public class RegisterNew {
    private JDialog dialog = null;
    private JTextField nameField = new JTextField(10);
    private JPasswordField passField = new JPasswordField(10);

    public RegisterNew(Window window, int axis) {
        dialog = new JDialog(window, "Register New", ModalityType.APPLICATION_MODAL);
        Container con = dialog.getContentPane();

        con.setLayout(new BoxLayout(con, axis));

        con.add(new JLabel("Enter your desired username"));
        con.add(nameField);
        con.add(new JLabel("Enter your password"));
        con.add(passField);
        con.add(new JButton(new AcceptAction()));
        dialog.pack();
        dialog.setLocationRelativeTo(window);

    }
    public char[] getPassword() {
        return passField.getPassword();
    }
    public String getUserName() {
        return nameField.getText();
    }
    public void setVisible(boolean b) {
        dialog.setVisible(b);
    }

    private class AcceptAction extends AbstractAction {
        public AcceptAction() {
            super("Accept");
            putValue(MNEMONIC_KEY, KeyEvent.VK_A);
        }

        @Override
        public void actionPerformed(ActionEvent e) {
            dialog.dispose();
        }
    }

}

如何使我的按钮在BoxLayout中做某事？

1 个答案: