Question

我已经完成了登录编码，当点击登录按钮时，应该从JPanel lp导航到JPanel ap。如果我的代码中有任何错误或修改，请帮助我。我检查了很多代码，并且我编辑了最大值，我更喜欢简单的步骤

import java.awt.*;
import javax.swing.*;
import javax.swing.border.LineBorder;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class LoginPage extends JFrame implements ActionListener
{   
   JLabel jl,jl2,jl3,jl4;
   JTextField jt,jt2;
   JTextArea jt1;
   JButton jb,jb2;
   JPanel lp, ap;

   JPasswordField pass,Passw;
    public static void main(String args[])
    {
      LoginPage jf=new LoginPage("Login");
      Dimension d=Toolkit.getDefaultToolkit().getScreenSize();
      int a=d.height/3;
      int b=d.width/12;
      jf.setBounds(a,b,660,500);
      jf.setResizable(false);
      jf.setVisible(true);
      jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      jf.setLayout(null);
    }
    public LoginPage(String title)
    {
       //First Panel containing Login details
       lp=new JPanel(); 
       lp.setLayout(null);

       jl=new JLabel("Login to your Account Safely");
       jl.setBounds(250,30,300,30);
       lp.add(jl);

       jl2=new JLabel("UserName");
       jl2.setBounds(100,150,100,30);
       lp.add(jl2);

       jt=new JTextField(JTextField.CENTER);
       jt.setBounds(250,150,300,25);
       jt.setBorder(new LineBorder(Color.BLACK));
       lp.add(jt);

       jl3=new JLabel("Password");
       jl3.setBounds(100,250,100,30);
       lp.add(jl3);

       pass=new JPasswordField(10);
    pass.setBounds(250,250,300,25);
    pass.setBorder(new LineBorder(Color.BLACK));
    lp.add(pass);


    jb=new JButton("Login");
    jb.setBounds(250,350,80,25);
    jb.setBorder(new LineBorder(Color.BLUE));
    jb.setCursor(new Cursor(Cursor.HAND_CURSOR));
    jb.addActionListener(this);
    lp.add(jb);


    jb2=new JButton("Cancel");
    jb2.setBounds(450,350,80,25);
    jb2.setBorder(new LineBorder(Color.RED));
    jb2.setCursor(new Cursor(Cursor.HAND_CURSOR));
    jb2.addActionListener(this);
    lp.add(jb2);
    add(lp);

    // Next Panel containing Account details
    ap=new JPanel();
    ap.setLayout(null);

    jl4=new JLabel("Login to your Account Safely");
    jl4.setBounds(250,30,300,30);
    ap.add(jl4);

    jt2=new JTextField(JTextField.CENTER);
    jt2.setBounds(250,150,300,25);
    jt2.setBorder(new LineBorder(Color.BLACK));
    ap.add(jt2);

}

public void actionPerformed(ActionEvent ae)
{
    if(ae.getSource()==jb)
    {
        if(("".equals(jt.getText())) || ("".equals(pass.getText())))
        {
            JOptionPane.showMessageDialog(null,"Username and Password fields are mandatory");
        }
        else if(("admin".equals(jt.getText())) && ("admin".equals(pass.getText())))
        {   
            lp.setVisible(false);
            add(ap);

        }
        else 
        {
            JOptionPane.showMessageDialog(null,"Invalid Username or Password");
        }
    }
    else if(ae.getSource()==jb2)
    {
        System.exit(0);
    }
}

}

Answer 1

这个问题可能就是你在寻找的东西：

How do I change JPanel inside a JFrame on the fly?

但是我会在你的情况下使用 CardLayout 。从框架添加/删除面板比看起来更复杂。

添加新的JPanel

1 个答案: