Re: Different cell editor in single column - Bug In Design?

On Jun 1, 9:23 am, Tom Hawtin <use...@tackline.plus.com> wrote:


Yes. I had tried that too. It won't work either.

OK. Let's take the following examples. In my JTable, all the cells
should be Object, except one of it (at col=1, row=1) should be Double.

When I mean a cell should be Double, it means the following :

1. I key in a non double value in the particular cell and try to press
enter to update my table model. It is not allowed and will display red
border around the cell as follow:
http://yancheng.cheok.googlepages.com/invalid-double-when-press-enter.JPG

2. I key in a double value in the particular cell and try to press
enter. Everything is ok as follow:
http://yancheng.cheok.googlepages.com/double-when-press-enter.JPG

I try two methods to achieve my objective. However, neither one does
work. When I key in non double value and press enter, the following
exception will be thrown :

Exception in thread "AWT-EventQueue-0"
java.lang.IllegalArgumentException: Cannot format given Object as a
Number
        at java.text.DecimalFormat.format(DecimalFormat.java:487)
        at java.text.Format.format(Format.java:140)

First method
---------------

package javaapplication7;

import javax.swing.*;
import javax.swing.table.*;

/**
 *
 * @author YC Cheok
 */
public class MyTable extends JTable {

    /** Creates a new instance of MyTable */
    public MyTable() {
    }

    public TableCellEditor getCellEditor(int row, int column) {
        if(row == 1 && column == 1) {
            return this.getDefaultEditor(Double.class);
        }

        return super.getCellEditor(row, column);
    }

    public TableCellRenderer getCellRenderer(int row, int column) {
        if(row == 1 && column == 1) {
            return this.getDefaultRenderer(Double.class);
        }

        return super.getCellRenderer(row, column);
    }
}

package javaapplication7;

/**
 *
 * @author YC Cheok
 */
public class NewJFrame extends javax.swing.JFrame {

    /** Creates new form NewJFrame */
    public NewJFrame() {
        initComponents();
    }

    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    // <editor-fold defaultstate="collapsed" desc=" Generated Code
">
    private void initComponents() {
        jScrollPane1 = new javax.swing.JScrollPane();
        jTable1 = new MyTable();

 
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
        jTable1.setModel(new javax.swing.table.DefaultTableModel(
            new Object [][] {
                {null, null, null, null},
                {null, null, null, null},
                {null, null, null, null},
                {null, null, null, null}
            },
            new String [] {
                "Title 1", "Title 2", "Title 3", "Title 4"
            }
        ));
        jScrollPane1.setViewportView(jTable1);

        getContentPane().add(jScrollPane1,
java.awt.BorderLayout.CENTER);

        pack();
    }// </editor-fold>

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new NewJFrame().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify
    private javax.swing.JScrollPane jScrollPane1;
    private javax.swing.JTable jTable1;
    // End of variables declaration

}

Second Method
-------------
package javaapplication7;

import javax.swing.*;
import javax.swing.table.*;
import javax.swing.table.DefaultTableCellRenderer;

/**
 *
 * @author YC Cheok
 */
public class MyTable extends JTable {

    /** Creates a new instance of MyTable */
    public MyTable() {
        final TableCellEditor oldEditor =
this.getDefaultEditor(Object.class);
        final TableCellRenderer oldRenderer =
this.getDefaultRenderer(Object.class);

        javax.swing.DefaultCellEditor editor = new
javax.swing.DefaultCellEditor(new JTextField()) {
            public java.awt.Component
getTableCellEditorComponent(JTable table, Object value, boolean
isSelected, int row, int column) {
                if(row == 1 && column == 1) {
                    TableCellEditor e =
table.getDefaultEditor(Double.class);
                    return e.getTableCellEditorComponent(table, value,
isSelected, row, column);
                }

                return oldEditor.getTableCellEditorComponent(table,
value, isSelected, row, column);
            }
        };

        javax.swing.table.DefaultTableCellRenderer renderer = new
javax.swing.table.DefaultTableCellRenderer() {
            public java.awt.Component
getTableCellRendererComponent(JTable table, Object value, boolean
isSelected, boolean hasFocus, int row, int column) {
                if(row == 1 && column == 1) {
                    TableCellRenderer e =
table.getDefaultRenderer(Double.class);
                    return e.getTableCellRendererComponent(table,
value, isSelected, hasFocus, row, column);
                }

                return
oldRenderer.getTableCellRendererComponent(table, value, isSelected,
hasFocus, row, column);
            }
        };

        this.setDefaultEditor(Object.class, editor);
        this.setDefaultRenderer(Object.class, renderer);
    }
}