JProgressBar not resetting to 0 or repainting

[Shaun Seah]

Hi guys,

I have a JSwing frame that queries a database and spits out results in a JTable.
I have included a JProgressBar to monitor as each record is retrieved after a button is pressed.

So far the code works when i click on my button the first time, however subsequent button clicks the JProgressBar does not reset to 0.

heres some code:

public class MyFrame extends JFrame {

    private JTabbedPane _tabbedPane;    
    public static JProgressBar _progressBar = new JProgressBar(0,100);

    public MyFrame() {
        super("MyFrame");

        Container contentPane = getContentPane();        
        _tabbedPane = new JTabbedPane();
        contentPane.add(_tabbedPane, BorderLayout.CENTER);
        _tabbedPane.add("Tab1", getFirstPanel());
        _tabbedPane.add("Tab2", getSecondPanel());
        contentPane.add(_progressBar, BorderLayout.SOUTH);

        addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent event) {
                System.exit(0);
            }
        });            
    }

    private JPanel getFirstPanel() {
        final JPanel panel = new JPanel();
        final JLabel labels... // bunch labels

        final JTextField textfields // bunch of textfields

        final JButton btnRetrieve = new JButton("Retrieve");
        final JTable table = new JTable();    

        btnRetrieve.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {                
                SwingUtilities.invokeLater(new Runnable() {    
                    public void run() {
                        try {
                            // Retrieve Data                            
                            ReportFrame._progressBar.setValue(0);                            
                            Collection<EmployeeBean> retList = dao.findAllEmployees();      // query the database and loop thru each record and increment the _progressBar.setValue(counter)
                            EmployeeTableModel tm = new EmployeeTableModel(retList);                                
                            table.setModel(tm);            

                            // repaint
                            table.repaint();

                        } catch (Exception ex) { 
                            ex.printStackTrace();
                        }
                    }
                }
                );
            }
        });

        JPanel topPanel = new JPanel();
        topPanel.setLayout(new FlowLayout());
        topPanel.add(labels, textfields....

        panel.setLayout(new BorderLayout());        
        panel.add(topPanel, BorderLayout.NORTH);        
        JScrollPane scrollpane = new JScrollPane(table);        
        panel.add(scrollpane, BorderLayout.SOUTH);
        panel.add(chartPanel, BorderLayout.CENTER);  

        return panel;
    }

Can anyone shed a light why the second time i click on retrive button the progressBar doest not reset to 0 and stays at 100%?

tks!

[Darryl Burke]

Because you're scheduling the long running task on the EDT instead of in a background Thread.

Go through the tutorial on Concurrency in Swing linked from the tutorial on How to Use Progress Bars, which again is linked from the API for JProgressBar.