我试图在 Swing 库界面上包含一个刷新按钮，该按钮的目的是在JTable调用添加/删除/更新查询后刷新 a 的内容。我做了一些研究，并tableDataChanged()从AbstractTableModel课堂上看到了这一点。问题是我不确定应该在哪里调用它。我是用的DefaultTableModel，所以我相信这个方法也可以用。
/*This is where I create the query and add the JTable to a scrollPane, an ResultsPanel
object is then added to a JFrame object*/
public class SitePanel extends JPanel implements Constants {
ResultsPanel resultsPanel = new ResultsPanel();
JTable table;
DefaultTableModel model;
JPanel sitePanel = new JPanel();
JPanel results = new JPanel();
public SitePanel(){
addComponents();
}
public void addComponents(){
sitePanel.setLayout(new BorderLayout());
sitePanel.add(buttonPanel, BorderLayout.NORTH);
sitePanel.add(resultsPanel, BorderLayout.CENTER);
sitePanel.setVisible(true);
add(new JScrollPane(sitePanel));
}
class ButtonPanel extends JPanel{
JPanel buttons = new JPanel();
public ButtonPanel(){
buttons.setLayout(new FlowLayout());
buttons.add(refreshButton);
show();
buttons.setVisible(true);
add(buttons);
}
public void show(){
refreshButton.addActionListener(new ActionListener(){
@Override
public void actionPerformed(ActionEvent arg0) {
new ResultsPanel();
table.setModel(model);
}
}
);
}
public class ResultsPanel extends JPanel{
public ResultsPanel(){
execute();
results.add(scrollPane);
javax.swing.SwingUtilities.invokeLater(new Runnable(){
public void run(){
results.setBorder(greenB);
results.setToolTipText("Results");
results.setVisible(true);
add(results);
}
});
}
public void execute() {
Vector columnNames = new Vector();
Vector data = new Vector();
try{
Connection conn = Connect.getConnection();
String query = "Select Name from Location Order By Name";
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(query);
ResultSetMetaData md = rs.getMetaData();
int columns = md.getColumnCount();
for (int i=1; i<=columns;i++){
columnNames.addElement(md.getColumnName(i));
}
while (rs.next()){
Vector row = new Vector(columns);
for(int i=1; i<=columns;i++){
row.addElement(rs.getObject(i));
}
data.addElement(row);
}
rs.close();
stmt.close();
conn.close();
}
catch (Exception e){
e.printStackTrace();
}
model = new DefaultTableModel(data, columnNames);
model.addTableModelListener(table);
table = new JTable(model){
public boolean isCellEditable(int row, int col){
return false;
}
public Class getColumnClass(int column){
for (int row=0; row<getRowCount();row++){
Object o = getValueAt(row, column);
if(o!=null){
return o.getClass();
}
}
return Object.class;
}
};
scrollPane = new JScrollPane(table);
scrollPane.setBorder(border);
scrollPane.getVerticalScrollBar().setBackground(Color.LIGHT_GRAY);
}
}
}
这是具有 main 方法的类。
import java.net.URL;
import java.sql.*;
import javax.swing.*;
public class Connect extends JFrame{
public static String user = null;
public static String password = null;
static Connection conn = null;
public static void loginGUI() throws Exception{
JPasswordField passwordField = new JPasswordField();
JTextField userField = new JTextField();
passwordField.setEchoChar('*');
Object[] obj = {"Username:\n", userField, "Password:\n", passwordField};
Object stringArray[] = {"OK", "Cancel"};
if(JOptionPane.showOptionDialog(null, obj, "Login", JOptionPane.YES_NO_OPTION, JOptionPane.QUESTION_MESSAGE, null, stringArray, obj)==JOptionPane.YES_OPTION);
password = new String (passwordField.getPassword());
user = userField.getText();
Conn.formConnection();
}
public static void main (String[] args) throws Exception{
javax.swing.SwingUtilities.invokeLater(new Runnable(){
public void run(){
try {
Connect.loginGUI();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Static connection class can only be created once at any given time.
* @author Nosheen Mahate
*
*/
public static class Conn{
public static Connection formConnection() throws Exception{
try{
String driver = "net.sourceforge.jtds.jdbc.Driver";
String url = "jdbc:jtds:sqlserver://BHX4DT-4FPQ35J:1433/Forecast;instance=SQLEXPRESS" +
";user=" +user +";password="+ password +";ssl=request;Encrypt=true;TrustServerCertificate=true";
Class.forName(driver);
conn = DriverManager.getConnection(url, user, password);
try{
password = null;
JFrame frame = new JFrame();
frame.add(new SitePanel());
frame.pack();
frame.setVisible(true);
}
catch (Exception e){
System.exit(1);
JOptionPane.showMessageDialog(null, e, "Error", JOptionPane.ERROR_MESSAGE);
e.printStackTrace();
}
}
catch (Exception e){
if(password != null || user !=null){
JOptionPane.showMessageDialog(null, e, "Error", JOptionPane.ERROR_MESSAGE);
}
else{
System.exit(1);
}
System.out.println("No Connection");
}
return conn;
}
/**
* Used to check that the connection is still established
*/
}
public static Connection getConnection(){
return conn;
}
/**
* Close the connection to the server
* @throws SQLException
*/
public static void closeConnection() throws SQLException{
conn.close();
conn = null;
}
}
我知道那里有很多代码，但我不太确定您可能需要什么。只是为了重新运行，我想知道JTable单击 后如何更新JButton，以及应该在哪里fireTableDataChanged()调用该方法（如果需要）。