Make a JCheckBox in a JTable editable

Question

I need some help with my JTable. I am writing a program, wich extracts data from a database into a JTable. The first column should be a editable JCheckBox so I am able to work with the checked (true or false) rows and the data.

I am using a AbstractTableModel(with class extends AbstractTableModel) and override these five methods:

    @Override
    public boolean isCellEditable(int rowIndex, int columnIndex) {
        return columnIndex == 0;
    }

    @Override
    public Class<?> getColumnClass(int col) {
        if (col == 0) {
            return Boolean.class;
        }
        return super.getColumnClass(col);
    }

    @Override
    public int getColumnCount() {
        return header.length;
    }

    @Override
    public int getRowCount() {
        return data.length;
    }

    @Override
    public Object getValueAt(int row, int col) {
        return data[row][col];
    }

To display the JTable I use:

JTable table = new JTable();
JScrollPane scrollpane = new JScrollPane();

. . .

table = new JTable(data, header);
table.setModel(this);
scrollpane = new JScrollPane(table);

I read the data with a for loop into the data array. The header array I defined. Basically I need the checked rows to send a mail with the right data in it.

EDIT:

package test;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.AbstractTableModel;

public class TestCode extends AbstractTableModel {
    private static final long serialVersionUID = -7051817393770003705L;

    String[] header = {"", "header", "header", "header"};
    Object[][] data = {{new Boolean(false), "Text", "Text", "Text"}, {new Boolean(false), "Text", "Text", "Text"}, {new Boolean(false), "Text", "Text", "Text"}};

    public TestCode() {
        JFrame frame = new JFrame();

        JTable table = new JTable(data, header);
        table.setModel(this);
        JScrollPane scrollpane = new JScrollPane(table);

        frame.add(scrollpane);

        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
    }
    @Override
    public boolean isCellEditable(int row, int col) {
        return col == 0;
    }

    @Override
    public Class<?> getColumnClass(int col) {
        if (col == 0) {
            return Boolean.class;
        }
        return super.getColumnClass(col);
    }

    @Override
    public int getColumnCount() {
        return header.length;
    }

    @Override
    public int getRowCount() {
        return data.length;
    }

    @Override
    public Object getValueAt(int row, int col) {
        return data[row][col];
    }

    public static void main(String[] args) {
        TestCode code = new TestCode();
    }
}

This is a short snippet of my code to execute to make it easier for you. I want be able to check the JCheckBoxes at the firt column so I am able to read a true or false boolen from that column.

Thank you for help!

what is your problem with it? Try making [SSCCE](http://www.sscce.org) also this line table.setModel(this) is awful, you shouldn't set that in the AbstractTableModel see `Single Responsability Principle` — nachokk, Aug 08 '13 at 12:55
My problem is that i can't check the JCheckBoxes at the first columns. — Gerret, Aug 08 '13 at 13:20

nachokk · Accepted Answer · 2013-08-08T13:33:24.123

3

You have to override AbstractTableModel#setValueAt

@Override
    public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
   //     super.setValueAt(aValue, rowIndex, columnIndex); by default empty implementation is not necesary if direct parent is AbstractTableModel
        data[rowIndex][columnIndex] = aValue; 
        fireTableCellUpdated(rowIndex, columnIndex);// notify listeners
    }

Result.

enter image description here

BTW : Don't use new Boolean(false) instead use Boolean.FALSE

edited Aug 08 '13 at 13:33

answered Aug 08 '13 at 13:28

nachokk

14,363
4
24
53

I thank you too very much! :) But I like the answer of Ruanae more becauze it is lightweight and I don't like it if the code is not easy to read. ^^ – Gerret Aug 08 '13 at 13:38
@Gerret take what you want, but is not correct..i only suggest you, to learn, as you know the gui follow `MVC` pattern so the model is a subject in the observer pattern so you have to notify observers when things changes... so you SHOULD call `fireTableCellUpdated(..)` – nachokk Aug 08 '13 at 13:42
1

@nachokk +1 for proper answer and notifier – mKorbel Aug 08 '13 at 15:14

score 1 · Answer 2 · answered Aug 08 '13 at 13:27

1

Okay leaving aside the structure of the code (I agree that the creation of the table should not be done in the model and things should be separated out better) the reason this is not working is that your table model does not implement setValueAt(Object value, int row, int column).

So when you click on a cell, that method is called, but your data array is not updated so the value for the cell is always false.

Adding

@Override
public void setValueAt(Object value, int row, int col) {
    data[row][col] = value;
}

to your model means the table behaves as you would expect

answered Aug 08 '13 at 13:27

Ruanae

85
1
6

I thank you very much ^^. I am actully program structured and clean but with GUI I don't have much experience! – Gerret Aug 08 '13 at 13:34
@Gerret this is not correct 100%, you have to notify listeners as i show in my answer – nachokk Aug 08 '13 at 13:37
Yes thats right but it works fine without at the moment. nachokks answer said it already and Ill keep that in mind. – Gerret Aug 08 '13 at 13:49

score 0 · Answer 3 · answered Aug 08 '13 at 13:36

0

Simply add implementation of value setter

    @Override
public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
data[rowIndex][columnIndex] = aValue;
}

answered Aug 08 '13 at 13:36

Antoniossss

31,590
6
57
99

Make a JCheckBox in a JTable editable

3 Answers3