JTable(my model is changed how do i update my view)?

hi all,
i want to know if there is a way to either alert my view (JTable) of my model (a class that extends AbsatractDataModel) dataq change.or a way to i can use so the model acknowledges the view when it's data change(a row added to an array list of type array of strings which represents the whole table data).?
i added data to my model a new row.anyway this addition does not get viewed on the aJTablke component till i re open the app, but i want to reflect this addition in the model to my JTable component.

hello,

beside methods in JTable, AbstractTableModel also has methods to notify the JTable about changes. The most universal one is fireTableDataChanged. Usually, you can always use that one. The other fire... methods might result in a better performance, but usually that would not be notable.

Kai

If you add a new row then use the

don't forget to increment your row count in the getRowCount method

If you have problems when adding a column then the ...

method should work fine.

// Mathias

ok here is my problem.i'm adding a row to an array list of type array of strings which represents the table data,getRowCount(){ returns the size of this array list }.i created a method and named it reflectAddition that takes an array of strings which represents my new row and added it to the array list and then called fireTableChanged() then called repaint on my JTable component and nothing were shown.i used getContentPane().remove(JTable componenet) and then added it.i used the method setValueAt() from my implementation of the AbstractTableModel and nothing were shown.my addition to the result set are not shwon till i re open my application from the beggining.i've been into these for many days so realy any help would be great.

i've seen a code to view an addition to the data in the model to the JTable componenet which was like this:
public void reflectAddition(String[] row)
{
data.add(row);//data represents an array list of type array of
//strings which represents the whole table data (rows of the table)
fireTableChanged(new TableModelEvent(data));
JTableComponent.repaint();
}
but this did not work with me either don't know what i'm missing.any ideas guys?

i re implemented the reflectAddition method as below:
reflectAddition()
{
jTable.tableChanged(new TableModelEvent(new GeneralTableModel()));
jTable.repaint();
}

doesn't this method recall the constructor for my model which alreday have the new data but it still don't show the addition till i re open my whole application.
wanna know how does the table knows how to get rows of data and columns.is it by using getRowCount(), getColumnCount(), getValueAt() methods? and what is the use of setValueAt() is it used to change the view or only apply changes to the model?

fireTableRowsInserted works for me, and there's no need to call repaint:

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.table.*;
import java.util.List;
 
public class MyModel extends AbstractTableModel {
    private List data = new ArrayList();
 
    public Object getValueAt(int row, int col) {return ((String[]) data.get(row))[col];}
    public int getColumnCount() {return 2;}
    public int getRowCount() {return data.size();}
 
    public void addRow(String[] rowData) {
        int row = data.size();
        data.add(rowData);
        fireTableRowsInserted(row, row);
    }
 
    public static void main(String[] args) {
        final MyModel model = new MyModel();
        JButton button = new JButton("add row");
        button.addActionListener(new ActionListener(){
            int count;
            public void actionPerformed(ActionEvent e) {
                model.addRow(new String[]{"#" + count++, "#" + count++});
            }
        });
        JFrame f = new JFrame("MyModel");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        Container cp = f.getContentPane();
        cp.add(new JScrollPane(new JTable(model)), BorderLayout.CENTER);
        cp.add(button, BorderLayout.SOUTH);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }
}

[ February 28, 2006: Message edited by: Jeff Albertson ]

That is a lot of code, and I'm sorry, but I don't have the time to sift though it. I posted a short example that worked. If your code isn't working, then you should post an equally short counterexample based on your code.
[ February 28, 2006: Message edited by: Jeff Albertson ]

i'm so sorry about the last post, really i'm.don't know i tryed to mimic my code as i could.here is the new code:

GeneralFrame.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class GeneralFrame extends JFrame
{
public GeneralFrame()
{
init();
}
private void init()
{
contentPane = getContentPane();
panel = new JPanel(new BorderLayout());

jTable1 = new JTable();
model = new Model();
jTable1.setModel(model);
scrollPane = new JScrollPane(jTable1);

addButton = new JButton("Add");
addButton.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent e)
{
addGeneralFrame agf = new addGeneralFrame();
agf.setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
agf.setVisible(true);
}

});

panel.add(scrollPane, BorderLayout.EAST);
panel.add(addButton, BorderLayout.SOUTH);
contentPane.add(panel);
setSize(400,400);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
GeneralFrame gf = new GeneralFrame();
gf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
gf.setVisible(true);

}
});
}
private Container contentPane ;
private JPanel panel;
private JTable jTable1;
private JScrollPane scrollPane;
private Model model ;
private JButton addButton;
}

Model.java

import java.util.*;
import java.sql.*;
import javax.swing.table.*;

public class Model extends AbstractTableModel{

public Model()
{
String[] row={"2736"};
tableData = new ArrayList<String[]>();
tableData.add(row);
}
public Object getValueAt(int row, int column)
{
String[] rowArray=(String[])tableData.get(row);
return rowArray[column];
}
public int getColumnCount() {
return columnNames.length;
}

public int getRowCount()
{
return tableData.size();
}
public void addRow(String[] row)
{
int firstRow = tableData.size();
tableData.add(row);
int lastRow = tableData.size();
fireTableRowsInserted(firstRow, lastRow);
}

private ArrayList<String[]> tableData;
private String[] columnNames = {"Case Number"};
}

addGeneralFrame.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class addGeneralFrame extends JFrame
{
public addGeneralFrame()
{
init();
}
private void init()
{
contentPane = getContentPane();
panel= new JPanel(new BorderLayout());

model = new Model();
caseNumText = new JTextField("");
submitButton = new JButton("Submit");

submitButton.addActionListener(new java.awt.event.ActionListener()
{
public void actionPerformed(java.awt.event.ActionEvent e)
{
String caseNumStr = caseNumText.getText();
String[] row = {caseNumStr };
model.addRow(row);
setVisible(false);
}
});

panel.add(caseNumText, BorderLayout.NORTH);
panel.add(submitButton, BorderLayout.SOUTH);
contentPane.add(panel);
setSize(400,400);
}

private Container contentPane;
private JPanel panel;
private JTextField caseNumText ;
private JButton submitButton;
private Model model ;
}

it is still not working.don't know why maybe because i'm using two frames and using different objects of the model so when the fireTableRowsInserted() occurrs it generates a TableEvent for a different oject other than the one that GeneralFrame uses?
thanks guys for replying.

I see two problems:

1. You have two frames and two instances of Model, when I think you only want one model. You could pass the exising model to the constructor for addGeneralFrame instead of creating an extra model there. This may not be the best design (why should the data entry window know there is a table involved) but it will get things running.

2. You window is cutting off the left side of cells so you can't see the entry. try calling pack() instead of setSize().

thanks alot guys.you really were a great help.i don't know how did i miss the concept passing by refrence but i think it may be cause i'm using JTable for the first time and i was in a bad mentall shape.
Thanks alot guys.
Regards,
Mahmoud Hadad

Keep up the good work!