在这个程序中，我必须创建一个GUI，将一个Contacts的对象保存到一个数组中，然后将该数组转换为一个数组，以传递给默认表模型的构造函数。 我知道我在这里做了一个额外的步骤。
备份按钮实际上将联系人Vector中的内容保存到二进制文件中。
加载按钮会将您放入用户名的文件名加载回向量中。
视图所有联系人应该显示向量中的所有内容（技术上是contactListArray）。
我遇到了这个问题，我无法让视图卡上的JTable更新。如果我加载联系人，然后单击加载它显示的联系人，所以我知道数据正在正确写入.dat文件。问题似乎是，一旦我点击视图按钮，JTable正在创建并且不会改变，即使我已将其设置为在方法中更改。
问题，我认为，问题在于if(source == viewBut)
我认为整个街区可能是问题所在。
提前感谢您的帮助，我真的很感激。
/*
* Lab number: Final Project
* Robert Lopez
* Section number: 4
*/
import javax.swing.*;
import javax.swing.table.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;
import javax.swing.event.*;
import javax.swing.table.TableModel;
class Contact implements Serializable{ String firstName, lastName, eAddress, address, phoneNum; }
public class finalLab implements ActionListener{
static CardLayout layout;
static private JFrame frame = new JFrame("Address Book");
static private JButton[] topMenuButton = new JButton[5];
static private Vector<Contact> contactList = new Vector<Contact>();
static private int contactSize = 0;
static private String[] columnNames = {"First Name", "Last Name","E-Mail Address", "Address", "Phone Number"};
static private String[][] contactListArray;
//START--------------------------Menu Card----------------------------------------------
static JPanel menuCard = new JPanel(new BorderLayout());
static JPanel menuTop = new JPanel( new GridLayout(2,1) );
static private JLabel firstLabel = new JLabel("Use The Buttons Below To Manage Contacts");
static JPanel menuMid = new JPanel(new FlowLayout());
static private JLabel userName = new JLabel("User Name:");
static private JTextField userNameField = new JTextField("", 15);
static private JLabel numContacts = new JLabel("Number of Contacts:");
static private JTextField numContactsField= new JTextField("", 15);
static private JPanel menuLower = new JPanel(new GridLayout(2,8));
static private JButton loadBut = new JButton("Load Contacts");
static private JButton addBut = new JButton("Add New Contacts");
static private JButton searchBut = new JButton("Search Contacts");
static private JButton sortBut = new JButton("Sort Contacts");
static private JButton deleteBut = new JButton("Delete Contacts");
static private JButton viewBut = new JButton("View All Contacts");
static private JButton backupBut = new JButton("Backup Contacts");
static private JButton blankBut = new JButton("");
//END---------------------------------Menu Card------------------------------------
//START---------------------------------View Card------------------------------------
//View Panel
static private JPanel viewCard = new JPanel(new BorderLayout());
static private JPanel viewCardLower = new JPanel();
static private JLabel viewLabel = new JLabel("Contact List");
static private JTable viewContacts;
static private JPanel viewCardMid = new JPanel(new BorderLayout());
static private JTableHeader header;
static private JScrollPane scrollPane = new JScrollPane();
//END---------------------------------View Card------------------------------------
//START-----------------------------------Delete Card------------------------------------
//Delete Panel
static private JPanel deleteCard = new JPanel(new GridLayout (3,1));
static private JPanel deleteMid = new JPanel();
static private JPanel deleteLower = new JPanel();
static private JLabel deleteLabel = new JLabel("Delete Contacts");
static private JLabel contactInfoLabel = new JLabel("Contact Phone #");
static private JTextField contactInfoField = new JTextField("", 15);
//END-----------------------------------Delete Card---------------------------------
//START-----------------------------------Add Contact-------------------------------
static private JPanel addCard = new JPanel(new GridLayout(6,2));
static private JLabel firstNameLabel = new JLabel("First Name");
static private JLabel lastNameLabel = new JLabel("Last Name");
static private JLabel eAddressLabel = new JLabel(" E-Mail Address");
static private JLabel addressLabel = new JLabel("Address");
static private JLabel phoneNumLabel = new JLabel("Phone No.");
static private JTextField firstNameField = new JTextField("", 10);
static private JTextField lastNameField = new JTextField("", 10);
static private JTextField eAddressField = new JTextField("", 10);
static private JTextField addressField = new JTextField("", 10);
static private JTextField phoneNumField = new JTextField("", 10);
static private JButton saveContactBut = new JButton("Save New Contact");
static private JPanel addLowerLeft = new JPanel();
static private JPanel addLowerRight = new JPanel();
//END------------------------------------Add Contact-----------------------------
//****************************** MAIN METHOD *******************************
static JPanel contentPane = (JPanel)frame.getContentPane();
static private JPanel mainPanel = new JPanel();
public static void main(String[] args){
ActionListener AL = new finalLab();
mainPanel.setLayout(layout = new CardLayout() );
contentPane.setLayout(new BorderLayout());
//Buttons, Labels
loadBut.addActionListener(AL);
for(int i = 0; i < 5; i++){
topMenuButton[i] = new JButton("Top Menu");
topMenuButton[i].addActionListener(AL);
}
backupBut.addActionListener(AL);
viewBut.addActionListener(AL);
addBut.addActionListener(AL);
deleteBut.addActionListener(AL);
saveContactBut.addActionListener(AL);
//-------------------------------------------------------
//Top Menu
firstLabel.setHorizontalAlignment(JTextField.CENTER);
firstLabel.setFont(new Font( "serif", Font.BOLD, 25 ));
menuTop.add(firstLabel);
numContactsField.setEditable(false);
numContactsField.setText("" + contactSize);
//Adding Middle Content
menuMid.add(userName);
menuMid.add(userNameField);
menuMid.add(numContacts);
menuMid.add(numContactsField);
//Adding Lower Content
menuLower.add(loadBut);
menuLower.add(addBut);
menuLower.add(searchBut);
menuLower.add(sortBut);
menuLower.add(deleteBut);
menuLower.add(viewBut);
menuLower.add(backupBut);
menuLower.add(blankBut);
menuCard.add(menuTop, BorderLayout.NORTH);
menuCard.add(menuMid, BorderLayout.CENTER);
menuCard.add(menuLower, BorderLayout.SOUTH);
//-------------------------------------------------------
//Delete Card
deleteLabel.setHorizontalAlignment(JTextField.CENTER);
deleteLabel.setFont(new Font( "serif", Font.BOLD, 25 ));
deleteCard.add(deleteLabel);
deleteMid.add(contactInfoLabel);
deleteMid.add(contactInfoField);
deleteCard.add(deleteMid);
deleteLower.add(topMenuButton[0]);
deleteCard.add(deleteLower);
//-------------------------------------------------------
//Add Card
firstNameLabel.setHorizontalAlignment(JTextField.RIGHT);
lastNameLabel.setHorizontalAlignment(JTextField.RIGHT);
eAddressLabel.setHorizontalAlignment(JTextField.RIGHT);
addressLabel.setHorizontalAlignment(JTextField.RIGHT);
phoneNumLabel.setHorizontalAlignment(JTextField.RIGHT);
addCard.add(firstNameLabel);
addCard.add(firstNameField);
addCard.add(lastNameLabel);
addCard.add(lastNameField);
addCard.add(eAddressLabel);
addCard.add(eAddressField);
addCard.add(addressLabel);
addCard.add(addressField);
addCard.add(phoneNumLabel);
addCard.add(phoneNumField);
addLowerLeft.add(saveContactBut);
addLowerRight.add(topMenuButton[1]);
addCard.add(addLowerLeft);
addCard.add(addLowerRight);
//----------------------------------------------------------
//View Card
viewLabel.setHorizontalAlignment(JTextField.CENTER);
viewLabel.setFont(new Font( "serif", Font.BOLD, 25 ));
viewCard.add(viewLabel, BorderLayout.NORTH);
viewCardLower.add(topMenuButton[2]);
viewCard.add(viewCardLower, BorderLayout.SOUTH);
//Adding to frame
mainPanel.add("Menu Card", menuCard);
mainPanel.add("Delete Card", deleteCard);
mainPanel.add("Add Card", addCard);
//mainPanel.add("View Card", viewCard);
contentPane.add(mainPanel);
layout.show(mainPanel, "Menu Card");
frame.pack();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(700, 275);
frame.setResizable(false);
frame.setVisible(true);
}
public void actionPerformed(ActionEvent e){
Object source =e.getSource();
if(source == loadBut){
try {
FileInputStream fis = new FileInputStream (userNameField.getText());
ObjectInputStream ois = new ObjectInputStream(fis);
contactList.clear();
contactSize = 0;
for(; true; contactSize++){
contactList.add( (Contact) ois.readObject() );
numContactsField.setText("" + (contactSize+1) );
}
} catch(EOFException e2){
} catch(Exception e2){
e2.printStackTrace();
}
}
if(source == addBut)
layout.show(mainPanel, "Add Card");
if(source == viewBut){
contactListArray = new String[contactSize][5];
for(int i = 0; i < contactSize; i++){
contactListArray[i][0] = contactList.get(i).firstName;
contactListArray[i][1] = contactList.get(i).lastName;
contactListArray[i][2] = contactList.get(i).eAddress;
contactListArray[i][3] = contactList.get(i).address;
contactListArray[i][4] = contactList.get(i).phoneNum;
}
DefaultTableModel model = new DefaultTableModel(contactListArray,columnNames);
viewContacts = new JTable(model);
header = viewContacts.getTableHeader();
viewContacts.setFillsViewportHeight(true);
viewContacts.revalidate();
viewCardMid.add(header, BorderLayout.NORTH);
viewCardMid.add(viewContacts, BorderLayout.CENTER);
viewCard.add(viewCardMid, BorderLayout.CENTER);
mainPanel.add("View Card", viewCard);
layout.show(mainPanel, "View Card");
}
if(source == deleteBut)
layout.show(mainPanel, "Delete Card");
if(source == saveContactBut){
contactList.add(new Contact());
contactList.get(contactSize).firstName = firstNameField.getText();
contactList.get(contactSize).lastName = lastNameField.getText();
contactList.get(contactSize).eAddress = eAddressField.getText();
contactList.get(contactSize).address = addressField.getText();
contactList.get(contactSize).phoneNum = phoneNumField.getText();
contactSize++;
firstNameField.setText("");
lastNameField.setText("");
eAddressField.setText("");
addressField.setText("");
phoneNumField.setText("");
}
if(source == backupBut){
try{
FileOutputStream fos = new FileOutputStream (userNameField.getText(), false);
ObjectOutputStream oos = new ObjectOutputStream(fos);
for(int i = 0; i < contactSize; i++)
oos.writeObject(contactList.get(i));
oos.close();
}
catch (IOException e2){
System.out.println("IO Exception " + e2);
}
}
for(int i = 0; i < 5; i++)
if(source == topMenuButton[i]){
layout.show(mainPanel, "Menu Card");
numContactsField.setText("" + contactSize);
}
}
}
答案 0 :(得分：2)
问题围绕着你对表格和CardLayout的工作方式缺乏了解......
// This is good...
DefaultTableModel model = new DefaultTableModel(contactListArray, columnNames);
// This is bad...
viewContacts = new JTable(model);
// This is bad...and raises some eyebrows
header = viewContacts.getTableHeader();
// This okay, but doesn't belong here, and is pointless given the following code...
viewContacts.setFillsViewportHeight(true);
// Pointless, you've not added the component to anything yet..
viewContacts.revalidate();
// ?? What ??
viewCardMid.add(header, BorderLayout.NORTH);
// Not good. The table should be added to a JScrollPane first and the scroll
// pane added to the card
viewCardMid.add(viewContacts, BorderLayout.CENTER);
// Okay, but wrong place...
viewCard.add(viewCardMid, BorderLayout.CENTER);
// Here is your main problem. The card layout only allows one component to exist
// for a given name. If you try and add another card, it is discarded and the first
// component with that name remains
mainPanel.add("View Card", viewCard);
// Not bad...
layout.show(mainPanel, "View Card");
在按下视图按钮时，不应创建表视图，而是在首次创建UI时应该初始化和查看，并在单击视图按钮时替换/更新表模型...
在构造函数中，您应该添加...
viewContacts = new JTable(); // Don't need the model at this stage
viewContacts.setFillsViewportHeight(true);
viewCardMid.add(new JScrollPane(viewContacts), BorderLayout.CENTER);
mainPanel.add("View Card", viewCard);
在您的视图按钮操作代码中......
DefaultTableModel model = new DefaultTableModel(contactListArray, columnNames);
viewContacts.setModel(model);
mainPanel.add("View Card", viewCard);
此外，正如开始指出的那样，您不应该使用static类字段，在您的情况下不需要它，并且随着程序复杂性的增加会导致问题。
您应该在执行动作的方法中使用if-else语句，这样可以减少逻辑错误的可能性并帮助提高性能
您还应该研究将每个视图的逻辑移动到它自己的类中，以减少主类中的混乱
请花些时间阅读Creating a GUI With JFC/Swing，特别是，我会调查How to use Tables和How to use CardLayout
答案 1 :(得分：0)
您将变量设为静态。静态变量的内存不是在堆栈上分配，而是在常规内存中分配。我没有详细查看你的代码，但我会尝试删除你班级中的所有静态变量，然后从那里再试一次。