因此，对于我目前正在学习的课程，我需要创建一个 ATM 系统。所以，我决定有2个面板。一个主面板，所有过程都在其中发生，一个选项面板，其中为用户列出了选项。如上所述，问题是我似乎无法删除主面板，因此我实际上可以用面板替换它，例如创建帐户屏幕。事实上，所发生的只是终端窗口显示。完全空白。据我检查，按钮事件正在触发，它甚至超过了删除功能。
无论如何，我似乎无法弄清楚问题是什么，也许是因为被按下的按钮也被面板删除了。这是相关的代码。
public class AccountSystem extends JFrame implements ActionListener
{
public static Account currentuser = new Account(); //This is so that the methods know which account is currently logged in so they can perform operations on it.
public static int count=0;
public static Account acc[] = new Account[1000];
public static String parts[] = new String[3];
private JButton login, logout, createacc, deposit1, deposit2, withdraw1, withdraw2, transfer1, transfer2, nevermind;
private JPanel options, mainarea, titlecard;
private JTextField username, password, transfer, depositarea, withdrawarea, retypearea;
private JLabel userprompt, depositprompt, withdrawpromt, balancedisp, passwordprompt, mainmessage, title;
private String newuser, newpass, newpassconfirm;
BorderLayout borderlayout;
GridLayout gridlayout;
public AccountSystem()
{
borderlayout = new BorderLayout();
borderlayout.setHgap(5);
borderlayout.setVgap(5);
//Establishing our buttons here.
JButton login = new JButton("Login");
login.addActionListener(this);
JButton createacc = new JButton("New Account");
createacc.addActionListener(this);
//Establishing our panels here.
JPanel options = new JPanel();
JPanel mainarea = new JPanel();
JPanel titlecard = new JPanel();
//Establishing our JLabel here.
JLabel userprompt = new JLabel("Username: ");
JLabel passwordprompt = new JLabel("Password: ");
JLabel title = new JLabel(" LOGIN ");
//Establishing our textfields here.
JTextField username = new JTextField(20);
JTextField password = new JTextField(20);
JTextField transfer = new JTextField(20);
JTextField withdrawarea = new JTextField(20);
//Building the GUI here.
titlecard.setSize(500,50);
titlecard.setLocation (0,0);
mainarea.setSize(300,450);
mainarea.setLocation(0,50);
options.setSize(150,450);
options.setLocation(300,50);
titlecard.add(title);
mainarea.add(userprompt);
mainarea.add(username);
mainarea.add(passwordprompt);
mainarea.add(password);
mainarea.add(login);
mainarea.add(createacc);
getContentPane().setLayout(null);
getContentPane().add(titlecard);
getContentPane().add(mainarea);
getContentPane().add(options);
}
}
public void actionPerformed (ActionEvent e)
{
if ((e.getActionCommand()).equals("Login"))
{
login();
}
else if ((e.getActionCommand()).equals("New Account"))
{
accountmaker();
}
else if ((e.getActionCommand()).equals("Deposit Funds"))
{
deposit();
}
else if ((e.getActionCommand()).equals("Withdraw Funds"))
{
withdraw();
}
else if ((e.getActionCommand()).equals("Withdraw"))
{
withdrawprocedure();
}
else if ((e.getActionCommand()).equals("Create Account"))
{
accountprocedure();
}
}
public void accountmaker() //This is the screen where the user creates the account they want to. Of course, something needed to be done to differentiate this screen and the login screen.
{
currentuser = null; //This is so that the program doesn't get somehow confused when dealing with multiple uses of the program.
getContentPane().remove(mainarea);
title.setText("Create New Account");
mainarea = new JPanel();
JLabel userprompt = new JLabel ("Username: ");
JLabel passwordprompt = new JLabel("Password: ");
JLabel retype = new JLabel ("Retype: "); //This is what makes it different from the login screen
createacc = new JButton ("Create Account");
createacc.addActionListener(this);
JButton nevermind = new JButton("Cancel");
nevermind.addActionListener(this);
JTextField username = new JTextField(20);
JTextField password = new JTextField(20);
retypearea = new JTextField(20);
mainarea.setSize(300,500);
mainarea.setLocation(0,0);
mainarea.add(userprompt);
mainarea.add(username);
mainarea.add(passwordprompt);
mainarea.add(password);
mainarea.add(retype);
mainarea.add(retypearea);
getContentPane().add(mainarea);
getContentPane().invalidate();
getContentPane().validate();
getContentPane().repaint();
}
这是程序使用的 Account 类。
public class Account
{
private String username;
private String password;
private double balance=0;
public void deposit (double deposit)
{
balance += deposit;
}
public void withdraw (double withdraw)
{
balance -= withdraw;
}
public void setBalance (double newbalance)
{
balance = newbalance;
}
public void setUsername (String newusername)
{
username = newusername;
}
public void setPassword (String newpassword)
{
password = newpassword;
}
public String getUsername ()
{
return username;
}
public double getbalance ()
{
return balance;
}
public String getpassword()
{
return password;
}
}