updating JProgressBar

[Altaf Ahmad]

Hi!
I'm trying to update values in a JProgressBar based on user selection but I can't seem to get the updated values to reflect in the progress bar.
I looked up past threads and Sun's site, from which I derived that it had to be done using invokeLater(). But it doesn't work still. The value is being updated in the object, but it just doesn't update the GUI.
Here's my routine:

public void loadProgressBar(int rowID){

System.out.println("Old gauge value is: " + bar.getValue());
System.out.println("Row is: " + rowID);
TableModel tmpModel  = selectionTable.getModel();
String goalID = (String) tmpModel.getValueAt(rowID,1);

Float floatGoal = new Float (goalID);

float f;
f = floatGoal.floatValue() * 10f;
final Float fGoalValue = new Float(f);


                
Runnable updateBar = new Runnable() {
    public void run() {
bar.setValue(fGoalValue.intValue());
bar.setString(fGoalValue.toString());
System.out.println("the value of the gauge is now " + bar.getValue());
            }
        };
    try {      
SwingUtilities.invokeLater(updateBar);
        }
        catch (Exception e) {
            e.printStackTrace();
        }

}
  

I'll appreciate if anybody could tell me what I'm doing wrong or where I could find relevant info! Any leads will be great!
Thanks,
Altaf

[Nathan Pruett]

I'm not sure what kind of calculations you are doing with the progress bar, but if your bar has a large range (i.e. 0-100), but your values are all very small ( i.e. 0 - 1 ), it won't be obvious when you update. It looks like the values in your table are floats, and you are multiplying them by 10. I think that means that your progress bar will go from 0 - 10... is this the case?

Here's some code I wrote to test your code. Everything seems to be working correctly... ?

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;
import java.awt.*;
 
public class ProgTester extends JFrame {
    
    private JProgressBar bar;
    private JTable selectionTable;
    
    public ProgTester() {
        selectionTable = new JTable( new MyModel() );
        ListSelectionModel selec = selectionTable.getSelectionModel();
        selec.addListSelectionListener( new RowSelectionListener() );
        JScrollPane scroll = new JScrollPane( selectionTable );
        getContentPane().add( scroll );
        bar = new JProgressBar( 0, 10 );
        bar.setStringPainted( true );
        getContentPane().add( bar, BorderLayout.SOUTH );
        setDefaultCloseOperation( EXIT_ON_CLOSE );
        setSize( 300, 300 );
        setVisible( true );
    }
    public void loadProgressBar(int rowID){
        System.out.println("Old gauge value is: " + bar.getValue());
        System.out.println("Row is: " + rowID);
 TableModel tmpModel  = selectionTable.getModel();
String goalID = (String) tmpModel.getValueAt(rowID,1);
Float floatGoal = new Float (goalID);
float f;
        f = floatGoal.floatValue() * 10f;
        final Float fGoalValue = new Float(f);
        Runnable updateBar = new Runnable() {
    public void run() {
bar.setValue(fGoalValue.intValue());
bar.setString(fGoalValue.toString());
System.out.println("the value of the gauge is now " + bar.getValue());
            }
        };
        try {
            SwingUtilities.invokeLater(updateBar);
        }
        catch (Exception e) {
            e.printStackTrace();        
        }
    }
 
    public static void main( String[] arg ) {
        new ProgTester();
    }
    
    private class MyModel extends DefaultTableModel {
        private Object[][] data = {
            { "Sam", "0.12" },
            { "Jack", "0.45" },
            { "Bob", "0.75" }
        };
        
        private String[] colNames = { "Number", "Name" };
        
        public MyModel() {
            setDataVector( data, colNames );
        }
    }
    
    private class RowSelectionListener implements ListSelectionListener {
        public void valueChanged( ListSelectionEvent e ) {
            if( e.getValueIsAdjusting() ) { 
                return;
            }
            ListSelectionModel lsm = (ListSelectionModel)e.getSource();
            if ( lsm.isSelectionEmpty() ) {
                return;
            }
            else {
                int selectedRow = lsm.getMinSelectionIndex();
                loadProgressBar( selectedRow );
            }
        }
    }
}

-Nate

[Altaf Ahmad]

Thanks Nate!
I'll test the code out and put a reply back in. The values in the model are from 1 to 10 and are float values. So, I'm multiplying them by 10 ( e.g. 6.3 becomes 63) and having the progress bar have a range of 0 - 100.
I don't have to display a series of progression - just one value (like a percentage value showing how much some task had been completed at a point in time). I read that if you process some code in a loop, then only the last value will be shown in the swing control because of the event control/thread implemention. That would work fine for me since I have to display only one value, but it just wouldn't update the display at all.
Anyway, I'll try out what you wrote. Again, thanks a lot!

[Altaf Ahmad]

Nate,
It's working great now! I don't really know what caused it to change behavior though. Initially, I put sections of your code in my app and it started working after some tweaking. But when I removed it, it still worked. I took out the Runnable section, made the ListSelectionListener back into an anonymous class, but it just works now for some reason!
I'm still trying to locate what it exactly is that's making it work now!
But thanks a lot for your help! :-)