创建 JTable 以显示数据时遇到问题
trouble with creating JTable to display data
我正在为学校做这个工资单项目。
这个想法是让用户从 ComboBox 输入员工的姓名、工作时间、小时费率和 select 部门。
将显示 3 个按钮，"Add More"、"Display Result" 和 "exit"。
"Add More" 按钮会将输入存储到多个 arryalist 中，并将文本字段设置为空白以允许更多输入。
"Display Result"会在底部的JPanel生成一个JTable，显示员工姓名、部门、周薪。
我 运行 遇到了点击 "Display Result" 按钮后没有任何显示的问题。也许我误解了按钮事件的目的，但我现在真的很困惑。请帮忙！
这是UI的photobucket directURL PrtSc，希望对您有所帮助。
import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
import java.util.*;
public class PayrollFrame extends JFrame
{
private JLabel nameMessageLabel, hourMessageLabel, rateMessageLabel, boxMessageLabel;
private JTextField nameTextField, hourTextField, rateTextField;
private JPanel inputPanel, buttonPanel, outputPanel, inputPanel1, inputPanel2, inputPanel3, inputPanel4;
private JComboBox<String> departmentBox;
private JButton addButton, displayButton, exitButton;
private JTable resultTable;
private String[] columnNames = {"Employee name", "Department", "Weekly Salary"};
private Object[][] data;
private int WINDOW_WIDTH = 400;
private int WINDOW_HEIGHT = 500;
ArrayList<String> name = new ArrayList<String>();
ArrayList<String> hour = new ArrayList<String>();
ArrayList<String> rate = new ArrayList<String>();
ArrayList<String> department = new ArrayList<String>();
ArrayList<String> salary = new ArrayList<String>();
private String[] departments = {"IT", "Marketing", "Human Resource", "Sales", "Customer Service", "Financial"};
/*default constructor*/
public PayrollFrame()
{
super("Payroll");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(WINDOW_WIDTH, WINDOW_HEIGHT);
setLayout(new GridLayout(3,1));
buildInputPanel();
buildButtonPanel();
buildOutputPanel();
add(inputPanel);
add(buttonPanel);
add(outputPanel);
setVisible(true);
}
private void buildInputPanel()
{
nameMessageLabel = new JLabel("Employee Name: ");
hourMessageLabel = new JLabel("Work Hour: ");
rateMessageLabel = new JLabel("Hourly Rate: ");
boxMessageLabel = new JLabel("Department: ");
nameTextField = new JTextField(10);
hourTextField = new JTextField(10);
rateTextField = new JTextField(10);
departmentBox = new JComboBox<String>(departments);
inputPanel = new JPanel();
inputPanel1 = new JPanel();
inputPanel2 = new JPanel();
inputPanel3 = new JPanel();
inputPanel4 = new JPanel();
inputPanel1.add(nameMessageLabel);
inputPanel1.add(nameTextField);
inputPanel2.add(hourMessageLabel);
inputPanel2.add(hourTextField);
inputPanel3.add(rateMessageLabel);
inputPanel3.add(rateTextField);
inputPanel4.add(boxMessageLabel);
inputPanel4.add(departmentBox);
inputPanel.add(inputPanel1);
inputPanel.add(inputPanel2);
inputPanel.add(inputPanel3);
inputPanel.add(inputPanel4);
}
private void buildButtonPanel()
{
addButton = new JButton("Add More");
addButton.addActionListener(new ButtonAction());
displayButton = new JButton("Display Result");
displayButton.addActionListener(new ButtonAction());
exitButton = new JButton("Exit");
exitButton.addActionListener(new ButtonAction());
buttonPanel = new JPanel();
buttonPanel.add(addButton);
buttonPanel.add(displayButton);
buttonPanel.add(exitButton);
}
private void buildOutputPanel()
{
outputPanel = new JPanel();
}
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData()
{
for(int i=0; i<name.size(); i++)
{
data[i][0]=name.get(i);
data[i][2]=department.get(i);
data[i][2]=salary.get(i);
}
resultTable = new JTable(data, columnNames);
outputPanel = new JPanel();
outputPanel.add(resultTable);
}
/*Function of 3 buttons*/
private class ButtonAction implements ActionListener
{
@Override
public void actionPerformed(ActionEvent e)
{
if(e.getActionCommand()=="Add More")
{
name.add(nameTextField.getText());
hour.add(hourTextField.getText());
rate.add(rateTextField.getText());
department.add((String) departmentBox.getSelectedItem());
calculateSalary(hourTextField.getText(), rateTextField.getText());
nameTextField.setText("");
hourTextField.setText("");
rateTextField.setText("");
}
else if(e.getActionCommand()=="Display Result")
{
printData();
}
else if(e.getActionCommand()=="Exit")
{
System.exit(0);
}
}
/*Calculate the weekly salary*/
private void calculateSalary(String hourString, String rateString)
{
int tempHour = Integer.parseInt(hourString);
double tempRate = Double.parseDouble(rateString);
if(tempHour<=40)
{
salary.add(Double.toString(tempHour * tempRate));
}
else
{
salary.add(Double.toString(40 * tempRate + (tempHour - 40) * (tempRate * 1.5))); //all hour after 40 will pay 1.5
}
}
}
}
让我们从……开始吧
if (e.getActionCommand() == "Add More") {
不是你在 Java 中比较 String 的方式，你需要使用 equals 方法来代替，比如...
if ("Add More".equals(e.getActionCommand())) {
例如
接下来你做...
add(inputPanel);
add(buttonPanel);
add(outputPanel);
其中，当使用BorderLayout时，将每个组件添加到BorderLayout内的默认位置，需要为每个组件提供位置约束，否则奇怪的事情开始发生，例如...
add(inputPanel, BorderLayout.NORTH);
add(buttonPanel, BorderLayout.CENTER);
add(outputPanel, BorderLayout.SOUTH);
我刚刚发现你用的是 GridLayout，就我个人而言，我认为 BorderLayout 你会得到更好的结果，但那是我
然后您创建了 resultTable 和 outputPanel 的新实例，但您从未将 outputPanel 添加到任何内容...
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData()
{
for(int i=0; i<name.size(); i++)
{
data[i][0]=name.get(i);
data[i][1]=department.get(i);
data[i][2]=salary.get(i);
}
resultTable = new JTable(data, columnNames);
outputPanel = new JPanel();
outputPanel.add(resultTable);
}
更好的办法是创建 resultTable，将其包裹在 JScrollPane 中并将其添加到您的屏幕。
当你想要"print"数据时，创建一个新的TableModel并将其应用到JTable
例如...
private void buildOutputPanel() {
outputPanel = new JPanel(new BorderLayout());
resultTable = new JTable();
outputPanel.add(new JScrollPane(resultTable));
}
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData() {
for (int i = 0; i < name.size(); i++) {
data[i][0] = name.get(i);
data[i][2] = department.get(i);
data[i][2] = salary.get(i);
}
DefaultTableModel model = new DefaultTableModel(data, columnNames);
resultTable.setModel(model);
}
查看 How to Use Tables and How to Use Scroll Panes 了解更多详情
例子
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;
public class PayrollFrame extends JFrame {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
PayrollFrame frame = new PayrollFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private JLabel nameMessageLabel, hourMessageLabel, rateMessageLabel, boxMessageLabel;
private JTextField nameTextField, hourTextField, rateTextField;
private JPanel inputPanel, buttonPanel, outputPanel, inputPanel1, inputPanel2, inputPanel3, inputPanel4;
private JComboBox<String> departmentBox;
private JButton addButton, displayButton, exitButton;
private JTable resultTable;
private String[] columnNames = {"Employee name", "Department", "Weekly Salary"};
private Object[][] data;
private int WINDOW_WIDTH = 400;
private int WINDOW_HEIGHT = 500;
ArrayList<String> name = new ArrayList<String>();
ArrayList<String> hour = new ArrayList<String>();
ArrayList<String> rate = new ArrayList<String>();
ArrayList<String> department = new ArrayList<String>();
ArrayList<String> salary = new ArrayList<String>();
private String[] departments = {"IT", "Marketing", "Human Resource", "Sales", "Customer Service", "Financial"};
/*default constructor*/
public PayrollFrame() {
super("Payroll");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
buildInputPanel();
buildButtonPanel();
buildOutputPanel();
add(inputPanel, BorderLayout.NORTH);
add(buttonPanel);
add(outputPanel, BorderLayout.SOUTH);
setVisible(true);
}
private void buildInputPanel() {
nameMessageLabel = new JLabel("Employee Name: ");
hourMessageLabel = new JLabel("Work Hour: ");
rateMessageLabel = new JLabel("Hourly Rate: ");
boxMessageLabel = new JLabel("Department: ");
nameTextField = new JTextField(10);
hourTextField = new JTextField(10);
rateTextField = new JTextField(10);
departmentBox = new JComboBox<String>(departments);
inputPanel = new JPanel();
inputPanel1 = new JPanel();
inputPanel2 = new JPanel();
inputPanel3 = new JPanel();
inputPanel4 = new JPanel();
inputPanel1.add(nameMessageLabel);
inputPanel1.add(nameTextField);
inputPanel2.add(hourMessageLabel);
inputPanel2.add(hourTextField);
inputPanel3.add(rateMessageLabel);
inputPanel3.add(rateTextField);
inputPanel4.add(boxMessageLabel);
inputPanel4.add(departmentBox);
inputPanel.add(inputPanel1);
inputPanel.add(inputPanel2);
inputPanel.add(inputPanel3);
inputPanel.add(inputPanel4);
}
private void buildButtonPanel() {
addButton = new JButton("Add More");
addButton.addActionListener(new ButtonAction());
displayButton = new JButton("Display Result");
displayButton.addActionListener(new ButtonAction());
exitButton = new JButton("Exit");
exitButton.addActionListener(new ButtonAction());
buttonPanel = new JPanel();
buttonPanel.add(addButton);
buttonPanel.add(displayButton);
buttonPanel.add(exitButton);
}
private void buildOutputPanel() {
outputPanel = new JPanel(new BorderLayout());
resultTable = new JTable();
outputPanel.add(new JScrollPane(resultTable));
}
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData() {
for (int i = 0; i < name.size(); i++) {
data[i][0] = name.get(i);
data[i][2] = department.get(i);
data[i][2] = salary.get(i);
}
TableModel model = new DefaultTableModel(data, columnNames);
resultTable.setModel(model);
}
/*Function of 3 buttons*/
private class ButtonAction implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
if ("Add More".equals(e.getActionCommand())) {
name.add(nameTextField.getText());
hour.add(hourTextField.getText());
rate.add(rateTextField.getText());
department.add((String) departmentBox.getSelectedItem());
calculateSalary(hourTextField.getText(), rateTextField.getText());
nameTextField.setText("");
hourTextField.setText("");
rateTextField.setText("");
} else if ("Display Result".equals(e.getActionCommand())) {
printData();
} else if ("Exit".equals(e.getActionCommand())) {
System.exit(0);
}
}
/*Calculate the weekly salary*/
private void calculateSalary(String hourString, String rateString) {
int tempHour = Integer.parseInt(hourString);
double tempRate = Double.parseDouble(rateString);
if (tempHour <= 40) {
salary.add(Double.toString(tempHour * tempRate));
} else {
salary.add(Double.toString(40 * tempRate + (tempHour - 40) * (tempRate * 1.5))); //all hour after 40 will pay 1.5
}
}
}
}
感谢@MadProgrammer 的帮助！他的回复帮助我解决了我遇到的许多问题，并且真的试图向我解释事情。在咨询了我的导师后，我通过编辑 printData 方法成功地编译并 运行 我的程序。
private void printData()
{
DefaultTableModel model = new DefaultTableModel(columnNames,name.size());
resultTable.setModel(model);
for(int i=0; i<name.size(); i++)
{
resultTable.setValueAt(name.get(i),i,0);
resultTable.setValueAt(department.get(i),i,1);
resultTable.setValueAt(salary.get(i),i,2);
}
}
我正在为学校做这个工资单项目。 这个想法是让用户从 ComboBox 输入员工的姓名、工作时间、小时费率和 select 部门。 将显示 3 个按钮，"Add More"、"Display Result" 和 "exit"。 "Add More" 按钮会将输入存储到多个 arryalist 中，并将文本字段设置为空白以允许更多输入。 "Display Result"会在底部的JPanel生成一个JTable，显示员工姓名、部门、周薪。
我 运行 遇到了点击 "Display Result" 按钮后没有任何显示的问题。也许我误解了按钮事件的目的，但我现在真的很困惑。请帮忙！
这是UI的photobucket directURL PrtSc，希望对您有所帮助。
import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
import java.util.*;
public class PayrollFrame extends JFrame
{
private JLabel nameMessageLabel, hourMessageLabel, rateMessageLabel, boxMessageLabel;
private JTextField nameTextField, hourTextField, rateTextField;
private JPanel inputPanel, buttonPanel, outputPanel, inputPanel1, inputPanel2, inputPanel3, inputPanel4;
private JComboBox<String> departmentBox;
private JButton addButton, displayButton, exitButton;
private JTable resultTable;
private String[] columnNames = {"Employee name", "Department", "Weekly Salary"};
private Object[][] data;
private int WINDOW_WIDTH = 400;
private int WINDOW_HEIGHT = 500;
ArrayList<String> name = new ArrayList<String>();
ArrayList<String> hour = new ArrayList<String>();
ArrayList<String> rate = new ArrayList<String>();
ArrayList<String> department = new ArrayList<String>();
ArrayList<String> salary = new ArrayList<String>();
private String[] departments = {"IT", "Marketing", "Human Resource", "Sales", "Customer Service", "Financial"};
/*default constructor*/
public PayrollFrame()
{
super("Payroll");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(WINDOW_WIDTH, WINDOW_HEIGHT);
setLayout(new GridLayout(3,1));
buildInputPanel();
buildButtonPanel();
buildOutputPanel();
add(inputPanel);
add(buttonPanel);
add(outputPanel);
setVisible(true);
}
private void buildInputPanel()
{
nameMessageLabel = new JLabel("Employee Name: ");
hourMessageLabel = new JLabel("Work Hour: ");
rateMessageLabel = new JLabel("Hourly Rate: ");
boxMessageLabel = new JLabel("Department: ");
nameTextField = new JTextField(10);
hourTextField = new JTextField(10);
rateTextField = new JTextField(10);
departmentBox = new JComboBox<String>(departments);
inputPanel = new JPanel();
inputPanel1 = new JPanel();
inputPanel2 = new JPanel();
inputPanel3 = new JPanel();
inputPanel4 = new JPanel();
inputPanel1.add(nameMessageLabel);
inputPanel1.add(nameTextField);
inputPanel2.add(hourMessageLabel);
inputPanel2.add(hourTextField);
inputPanel3.add(rateMessageLabel);
inputPanel3.add(rateTextField);
inputPanel4.add(boxMessageLabel);
inputPanel4.add(departmentBox);
inputPanel.add(inputPanel1);
inputPanel.add(inputPanel2);
inputPanel.add(inputPanel3);
inputPanel.add(inputPanel4);
}
private void buildButtonPanel()
{
addButton = new JButton("Add More");
addButton.addActionListener(new ButtonAction());
displayButton = new JButton("Display Result");
displayButton.addActionListener(new ButtonAction());
exitButton = new JButton("Exit");
exitButton.addActionListener(new ButtonAction());
buttonPanel = new JPanel();
buttonPanel.add(addButton);
buttonPanel.add(displayButton);
buttonPanel.add(exitButton);
}
private void buildOutputPanel()
{
outputPanel = new JPanel();
}
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData()
{
for(int i=0; i<name.size(); i++)
{
data[i][0]=name.get(i);
data[i][2]=department.get(i);
data[i][2]=salary.get(i);
}
resultTable = new JTable(data, columnNames);
outputPanel = new JPanel();
outputPanel.add(resultTable);
}
/*Function of 3 buttons*/
private class ButtonAction implements ActionListener
{
@Override
public void actionPerformed(ActionEvent e)
{
if(e.getActionCommand()=="Add More")
{
name.add(nameTextField.getText());
hour.add(hourTextField.getText());
rate.add(rateTextField.getText());
department.add((String) departmentBox.getSelectedItem());
calculateSalary(hourTextField.getText(), rateTextField.getText());
nameTextField.setText("");
hourTextField.setText("");
rateTextField.setText("");
}
else if(e.getActionCommand()=="Display Result")
{
printData();
}
else if(e.getActionCommand()=="Exit")
{
System.exit(0);
}
}
/*Calculate the weekly salary*/
private void calculateSalary(String hourString, String rateString)
{
int tempHour = Integer.parseInt(hourString);
double tempRate = Double.parseDouble(rateString);
if(tempHour<=40)
{
salary.add(Double.toString(tempHour * tempRate));
}
else
{
salary.add(Double.toString(40 * tempRate + (tempHour - 40) * (tempRate * 1.5))); //all hour after 40 will pay 1.5
}
}
}
}
让我们从……开始吧
if (e.getActionCommand() == "Add More") {
不是你在 Java 中比较 String 的方式，你需要使用 equals 方法来代替，比如...
if ("Add More".equals(e.getActionCommand())) {
例如
接下来你做...
add(inputPanel);
add(buttonPanel);
add(outputPanel);
其中，当使用BorderLayout时，将每个组件添加到BorderLayout内的默认位置，需要为每个组件提供位置约束，否则奇怪的事情开始发生，例如...
add(inputPanel, BorderLayout.NORTH);
add(buttonPanel, BorderLayout.CENTER);
add(outputPanel, BorderLayout.SOUTH);
我刚刚发现你用的是 GridLayout，就我个人而言，我认为 BorderLayout 你会得到更好的结果，但那是我
然后您创建了 resultTable 和 outputPanel 的新实例，但您从未将 outputPanel 添加到任何内容...
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData()
{
for(int i=0; i<name.size(); i++)
{
data[i][0]=name.get(i);
data[i][1]=department.get(i);
data[i][2]=salary.get(i);
}
resultTable = new JTable(data, columnNames);
outputPanel = new JPanel();
outputPanel.add(resultTable);
}
更好的办法是创建 resultTable，将其包裹在 JScrollPane 中并将其添加到您的屏幕。
当你想要"print"数据时，创建一个新的TableModel并将其应用到JTable
例如...
private void buildOutputPanel() {
outputPanel = new JPanel(new BorderLayout());
resultTable = new JTable();
outputPanel.add(new JScrollPane(resultTable));
}
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData() {
for (int i = 0; i < name.size(); i++) {
data[i][0] = name.get(i);
data[i][2] = department.get(i);
data[i][2] = salary.get(i);
}
DefaultTableModel model = new DefaultTableModel(data, columnNames);
resultTable.setModel(model);
}
查看 How to Use Tables and How to Use Scroll Panes 了解更多详情
例子
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;
public class PayrollFrame extends JFrame {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
PayrollFrame frame = new PayrollFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private JLabel nameMessageLabel, hourMessageLabel, rateMessageLabel, boxMessageLabel;
private JTextField nameTextField, hourTextField, rateTextField;
private JPanel inputPanel, buttonPanel, outputPanel, inputPanel1, inputPanel2, inputPanel3, inputPanel4;
private JComboBox<String> departmentBox;
private JButton addButton, displayButton, exitButton;
private JTable resultTable;
private String[] columnNames = {"Employee name", "Department", "Weekly Salary"};
private Object[][] data;
private int WINDOW_WIDTH = 400;
private int WINDOW_HEIGHT = 500;
ArrayList<String> name = new ArrayList<String>();
ArrayList<String> hour = new ArrayList<String>();
ArrayList<String> rate = new ArrayList<String>();
ArrayList<String> department = new ArrayList<String>();
ArrayList<String> salary = new ArrayList<String>();
private String[] departments = {"IT", "Marketing", "Human Resource", "Sales", "Customer Service", "Financial"};
/*default constructor*/
public PayrollFrame() {
super("Payroll");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout());
buildInputPanel();
buildButtonPanel();
buildOutputPanel();
add(inputPanel, BorderLayout.NORTH);
add(buttonPanel);
add(outputPanel, BorderLayout.SOUTH);
setVisible(true);
}
private void buildInputPanel() {
nameMessageLabel = new JLabel("Employee Name: ");
hourMessageLabel = new JLabel("Work Hour: ");
rateMessageLabel = new JLabel("Hourly Rate: ");
boxMessageLabel = new JLabel("Department: ");
nameTextField = new JTextField(10);
hourTextField = new JTextField(10);
rateTextField = new JTextField(10);
departmentBox = new JComboBox<String>(departments);
inputPanel = new JPanel();
inputPanel1 = new JPanel();
inputPanel2 = new JPanel();
inputPanel3 = new JPanel();
inputPanel4 = new JPanel();
inputPanel1.add(nameMessageLabel);
inputPanel1.add(nameTextField);
inputPanel2.add(hourMessageLabel);
inputPanel2.add(hourTextField);
inputPanel3.add(rateMessageLabel);
inputPanel3.add(rateTextField);
inputPanel4.add(boxMessageLabel);
inputPanel4.add(departmentBox);
inputPanel.add(inputPanel1);
inputPanel.add(inputPanel2);
inputPanel.add(inputPanel3);
inputPanel.add(inputPanel4);
}
private void buildButtonPanel() {
addButton = new JButton("Add More");
addButton.addActionListener(new ButtonAction());
displayButton = new JButton("Display Result");
displayButton.addActionListener(new ButtonAction());
exitButton = new JButton("Exit");
exitButton.addActionListener(new ButtonAction());
buttonPanel = new JPanel();
buttonPanel.add(addButton);
buttonPanel.add(displayButton);
buttonPanel.add(exitButton);
}
private void buildOutputPanel() {
outputPanel = new JPanel(new BorderLayout());
resultTable = new JTable();
outputPanel.add(new JScrollPane(resultTable));
}
/*Copy ArrayList into 2D array to display in JTable format*/
private void printData() {
for (int i = 0; i < name.size(); i++) {
data[i][0] = name.get(i);
data[i][2] = department.get(i);
data[i][2] = salary.get(i);
}
TableModel model = new DefaultTableModel(data, columnNames);
resultTable.setModel(model);
}
/*Function of 3 buttons*/
private class ButtonAction implements ActionListener {
@Override
public void actionPerformed(ActionEvent e) {
if ("Add More".equals(e.getActionCommand())) {
name.add(nameTextField.getText());
hour.add(hourTextField.getText());
rate.add(rateTextField.getText());
department.add((String) departmentBox.getSelectedItem());
calculateSalary(hourTextField.getText(), rateTextField.getText());
nameTextField.setText("");
hourTextField.setText("");
rateTextField.setText("");
} else if ("Display Result".equals(e.getActionCommand())) {
printData();
} else if ("Exit".equals(e.getActionCommand())) {
System.exit(0);
}
}
/*Calculate the weekly salary*/
private void calculateSalary(String hourString, String rateString) {
int tempHour = Integer.parseInt(hourString);
double tempRate = Double.parseDouble(rateString);
if (tempHour <= 40) {
salary.add(Double.toString(tempHour * tempRate));
} else {
salary.add(Double.toString(40 * tempRate + (tempHour - 40) * (tempRate * 1.5))); //all hour after 40 will pay 1.5
}
}
}
}
感谢@MadProgrammer 的帮助！他的回复帮助我解决了我遇到的许多问题，并且真的试图向我解释事情。在咨询了我的导师后，我通过编辑 printData 方法成功地编译并 运行 我的程序。
private void printData()
{
DefaultTableModel model = new DefaultTableModel(columnNames,name.size());
resultTable.setModel(model);
for(int i=0; i<name.size(); i++)
{
resultTable.setValueAt(name.get(i),i,0);
resultTable.setValueAt(department.get(i),i,1);
resultTable.setValueAt(salary.get(i),i,2);
}
}