因此，对于我目前正在上的课，我需要创建一个ATM系统。因此，我决定有2个面板。在其中执行所有过程的主面板，以及在其中为用户列出选项的选项面板。如上所述，问题是我似乎无法移除主面板，因此实际上可以用面板替换它，例如创建帐户屏幕。实际上，所发生的只是终端窗口显示。完全空白。据我检查，button事件正在触发，甚至超过了remove函数。
无论如何，我似乎无法弄清楚问题出在哪里，也许是因为面板上的按钮也被删除了。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;
}
}
最佳答案
如果我理解正确，那么您基本上需要在某些情况下用帐户面板替换主面板！
我已经编写了示例代码（请根据您的项目进行修改）
在这段代码中。我创建了4个面板，分别是
组件面板：用于容纳所有组件
主面板：包含带有“主面板”文本的标签，其边框被涂成红色
帐户面板：包含带有“帐户面板”文字的标签，其边框被涂成绿色
选项面板：带边框的空白面板被涂成蓝色
两个按钮：
帐户按钮：应该用“帐户面板”替换“主面板”
主按钮：应该用主面板替换“帐户面板”
使用GridBagLayout，您所需要做的就是将主面板和帐户面板放置在同一位置，即两者的gridx = 0和gridy = 0。首先应显示主面板。在事件“帐户按钮”上，将主面板的可见性设置为false，将帐户面板的可见性设置为true。对于事件“主按钮”，反之亦然。 GridBagLayout是一种出色的动态布局，它通过其lef来管理空白间距而没有任何变形。
public class SwingSolution extends JFrame implements ActionListener
{
private JPanel componentPanel = null;
private JPanel mainPanel = null;
private JLabel mainLabel = null;
private JPanel optionPanel = null;
private JPanel accountPanel = null;
private JLabel accountLabel = null;
private JButton replaceToAccountPanel = null;
private JButton replaceToMainPanel = null;
private final static String MAIN_TO_ACCOUNT = "MainToAccount";
private final static String ACCOUNT_TO_MAIN = "AccountToMain";
public JPanel getComponentPanel()
{
if(null == componentPanel)
{
componentPanel = new JPanel();
GridBagLayout gridBagLayout = new GridBagLayout();
componentPanel.setLayout(gridBagLayout);
GridBagConstraints constraint = new GridBagConstraints();
constraint.insets = new Insets(10, 10, 10, 10);
mainPanel = new JPanel();
constraint.gridx = 0;
constraint.gridy = 0;
mainPanel.setMinimumSize(new Dimension(100, 50));
mainPanel.setPreferredSize(new Dimension(100, 50));
mainPanel.setMaximumSize(new Dimension(100, 50));
mainPanel.setBorder(
BorderFactory.createLineBorder(Color.RED));
mainLabel = new JLabel("Main Panel");
mainPanel.add(mainLabel);
componentPanel.add(mainPanel, constraint);
accountPanel = new JPanel();
constraint.gridx = 0;
constraint.gridy = 0;
accountPanel.setMinimumSize(new Dimension(100, 50));
accountPanel.setPreferredSize(new Dimension(100, 50));
accountPanel.setMaximumSize(new Dimension(100, 50));
accountPanel.setBorder(
BorderFactory.createLineBorder(Color.GREEN));
accountLabel = new JLabel("Account Panel");
accountPanel.add(accountLabel);
componentPanel.add(accountPanel, constraint);
optionPanel = new JPanel();
constraint.gridx = 0;
constraint.gridy = 1;
optionPanel.setMinimumSize(new Dimension(100, 50));
optionPanel.setPreferredSize(new Dimension(100, 50));
optionPanel.setMaximumSize(new Dimension(100, 50));
optionPanel.setBorder(
BorderFactory.createLineBorder(Color.BLUE));
componentPanel.add(optionPanel, constraint);
replaceToAccountPanel = new JButton("Account Button");
replaceToAccountPanel.setName(MAIN_TO_ACCOUNT);
constraint.gridx = 0;
constraint.gridy = 2;
replaceToAccountPanel.setSize(new Dimension(800, 30));
replaceToAccountPanel.addActionListener(this);
componentPanel.add(replaceToAccountPanel, constraint);
replaceToMainPanel = new JButton("Main Button");
replaceToMainPanel.setName(ACCOUNT_TO_MAIN);
constraint.gridx = 1;
constraint.gridy = 2;
replaceToMainPanel.setMinimumSize(new Dimension(800, 30));
replaceToMainPanel.addActionListener(this);
componentPanel.add(replaceToMainPanel, constraint);
}
return componentPanel;
}
public void actionPerformed (ActionEvent evt)
{
JButton buttonClicked = (JButton) evt.getSource();
if(buttonClicked != null)
{
if(buttonClicked.getName().equals(MAIN_TO_ACCOUNT))
{
mainPanel.setVisible(false);
accountPanel.setVisible(true);
}
else if(buttonClicked.getName().equals(ACCOUNT_TO_MAIN))
{
mainPanel.setVisible(true);
accountPanel.setVisible(false);
}
}
}
public static void main(String[] args)
{
JFrame frame = new JFrame();
SwingSolution main = new SwingSolution();
frame.setTitle("Simple example");
frame.setSize(400, 300);
frame.setLocationRelativeTo(null);
frame.setContentPane(main.getComponentPanel());
frame.setVisible(true);
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
}
}