Checkbox in only one JTable Cell

Question

I want to create an JTable with 2 columns, which looks like a survey. So on the left are the questions and on the right the user can give his answers. But in one li

Answer 1

You can implement the interface TableCellRenderer to create a custom renderer for cells that have different objects, like a JTextField and JLabel. You must implement the method getTableCellRendererComponent and from it you can return a component (like a JPanel or what you wish) with the components that you wish to show on the cell. In the table, you will use JTable.setDefaultRenderer() to set your new renderer for a custom class.

If you have only 2 values, maybe you can also set your data to boolean values and let the table display it as a CheckBox (default rendering).

This is the code for the second method, which seems to be more like what you want.

class CheckBoxModel extends AbstractTableModel{

        private final Object[][] rowData = {{"John" , true}, {"Mary", false}};
        final String columnNames[] = { "Student", "Approve" };

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

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

        @Override
        public Class getColumnClass(final int columnIndex) {
            if (columnIndex == 1) {
                return Boolean.class; //renders column as a CheckBox
            }
            return super.getColumnClass(columnIndex);
        }

        @Override
        public Object getValueAt(final int rowIndex, final int columnIndex) {
            return rowData[rowIndex][columnIndex];
        }

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

        @Override
        public boolean isCellEditable(final int rowIndex, final int columnIndex) {
            return true;    //makes all cells editable
        }
}

And a test class:

public class TestTable {

    public static void main(String[] args) {
        final JFrame frame = new JFrame("Editable Color Table");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        final JTable table = new JTable(new CheckBoxModel());
        final JScrollPane scrollPane = new JScrollPane(table);
        frame.add(scrollPane, BorderLayout.CENTER);
        frame.setSize(500, 500);
        frame.setVisible(true);
    }
}