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How to change the color of JTable cell after button click?

This code creates a table with cells as ImageIcon.class. By clicking the button I want be able to change the color of ImageIcon in a corresponding cell. The code sets background of the whole cell if I delete "c instanceof Icon". Otherwise, the color is not changed at all. I want to change exactly the color of 16x16 icon as specified in a renderer.
public class Test {
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame f = new JFrame("CheckTable");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTable tableCabin = new JTable(new CabinTableModel(nrows,ncols));
TableCellRenderer defaultRenderer = tableCabin.getDefaultRenderer(ImageIcon.class);
tableCabin.setDefaultRenderer(ImageIcon.class, new CabinColumnRenderer(defaultRenderer)
{
#Override
public Component getTableCellRendererComponent(JTable table,
Object value, boolean isSelected, boolean hasFocus, int row,
int column) {
Component c = super.getTableCellRendererComponent(table, value, isSelected, hasFocus,
row, column);
if (c instanceof Icon)
{
if (row == selectedRow && column == 1)
{
c.setForeground(Color.black);
c.setBackground(Color.red);
}
else
{
c.setForeground(Color.black);
c.setBackground(null);
}
}
return c;
}
});
JTextField textfield = new JTextField(10);
textfield.setText("5");
JButton but = new JButton("Set");
but.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent e) {
selectedRow = Integer.parseInt(textfield.getText().toString());
table.repaint();
}
});
f.add(table);
f.add(textfield);
f.add(but);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
});
}
}
import java.awt.Color;
import java.awt.Component;
import javax.swing.Icon;
import javax.swing.JTable;
import javax.swing.table.TableCellRenderer;
public class CabinColumnRenderer implements TableCellRenderer
{
private TableCellRenderer delegate;
public CabinColumnRenderer(TableCellRenderer defaultRenderer)
{
this.delegate = defaultRenderer;
}
public Component getTableCellRendererComponent(JTable table, Object value,
boolean isSelected, boolean hasFocus, int row, int column)
{
Component c = delegate.getTableCellRendererComponent(table, value, isSelected,
hasFocus, row, column);
if (c instanceof Icon)
{
c.setBackground(Color.red);
}
return c;
}
}
import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.util.ArrayList;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.table.AbstractTableModel;
#SuppressWarnings("serial")
public class CabinTableModel extends AbstractTableModel
{
private String columnNames[];
private Class<?>[] columns;
private int rows;
private int cols;
private ArrayList<Object[]> data;
public CabinTableModel(int rows, int cols)
{
this.rows = rows;
this.cols = cols;
columnNames = new String[cols];
columns = new Class<?>[cols];
for (int i=0; i<cols; i++)
{
columns[i] = ImageIcon.class;
columnNames[i] = "A"+i;
}
this.data = new ArrayList<Object[]>();
for (int i = 0; i < rows; i++)
{
Object[] row = new Object[this.cols];
this.data.add(row);
for (int j=1; j<cols; j++)
row[j] = createIcon();
}
}
private Icon createIcon()
{
return new Icon()
{
private Color color = Color.green;
public int getIconHeight()
{
return 16;
}
public int getIconWidth()
{
return 16;
}
public void paintIcon(Component c, Graphics g, int x, int y)
{
g.setColor(color);
g.fillRect(x, y, getIconWidth(), getIconHeight());
}
};
}
#Override
public Class<?> getColumnClass(int columnIndex)
{
return this.columns[columnIndex];
}
public int getColumnCount()
{
return cols;
}
public int getRowCount()
{
return rows;
}
public Object getValueAt(int row, int col)
{
return data.get(row)[col];
}
#Override
public String getColumnName(int col)
{
return columnNames[col];
}
#Override
public boolean isCellEditable(int rowIndex, int columnIndex)
{
return false;
}
#Override
public void setValueAt(Object value, int row, int col)
{
data.get(row)[col] = value;
fireTableCellUpdated(row, col);
}
public void deleteRows(int startIndex, int count)
{
int index = startIndex + count - 1;
while (index >= startIndex)
{
data.remove(index);
index--;
}
fireTableRowsDeleted(startIndex, startIndex + count - 1);
}
}

How to change rows with columns in JTable?

I have created my JTable like this:
String[] columns = {"Country", "Continent", "Latitude", "Longitude"};
String[][] data = {{"A","B","C","D"}};
table = new JTable(data,columns);
JScrollPane spTable = new JScrollPane(table);
panel2.add(spTable);
Now I want to change the look of the table in such a way that rows will be exchanged with columns, meaning that the table will have 4 rows and 1 column. Could not find such function between member methods, is it possible? Thanks.

To do that, I would consider a custom TableModel which can handle a "toggled" state.
From your example, the result may be surprizing but this code shows you the general idea and allows you to swap rows and columns with a button.
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Arrays;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.AbstractTableModel;
public class TestTable {
private static class TogglingTableModel extends AbstractTableModel {
private boolean toggled = false;
private final Object[][] data;
private final Object[] columnNames;
public TogglingTableModel(Object[][] data, Object[] columnNames) {
this.columnNames = columnNames;
this.data = data;
normalizeData();
}
private void normalizeData() {
for (int i = 0; i < data.length; i++) {
Object[] o = data[i];
if (o.length < columnNames.length) {
data[i] = Arrays.copyOf(o, columnNames.length);
}
}
}
#Override
public String getColumnName(int column) {
if (toggled) {
Object valueAt;
if (column == 0) {
valueAt = columnNames[0];
} else {
valueAt = data[column - 1][0];
}
return valueAt != null ? valueAt.toString() : null;
} else {
Object object = columnNames[column];
return object != null ? object.toString() : null;
}
}
#Override
public boolean isCellEditable(int rowIndex, int columnIndex) {
return true;
}
#Override
public int getColumnCount() {
if (toggled) {
return data.length + 1;
} else {
return columnNames.length;
}
}
#Override
public int getRowCount() {
if (toggled) {
return columnNames.length - 1;
} else {
return data.length;
}
}
#Override
public Object getValueAt(int row, int column) {
if (toggled) {
if (column == 0) {
return columnNames[row + 1];
} else {
return data[column - 1][row + 1];
}
} else {
return data[row][column];
}
}
#Override
public void setValueAt(Object aValue, int row, int column) {
if (toggled) {
if (column == 0) {
columnNames[row + 1] = aValue;
} else {
data[column - 1][row + 1] = aValue;
}
} else {
data[row][column] = aValue;
}
}
public boolean isToggled() {
return toggled;
}
public void toggle() {
toggled = !toggled;
fireTableStructureChanged();
}
}
private TogglingTableModel tableModel;
public TestTable() {
JFrame frame = new JFrame(TestTable.class.getSimpleName());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
String[] columns = { "Country", "Continent", "Latitude", "Longitude" };
String[][] data = { { "A" }, { "B" }, { "C" }, { "D" }, { "E" } };
tableModel = new TogglingTableModel(data, columns);
JTable table = new JTable(tableModel);
JPanel buttonPanel = new JPanel();
JButton togglingButton = new JButton("Toggle table");
togglingButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
tableModel.toggle();
}
});
buttonPanel.add(togglingButton);
frame.add(new JScrollPane(table));
frame.add(buttonPanel, BorderLayout.SOUTH);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
TestTable fs = new TestTable();
}
});
}
}

Java, change a cell content as a function of another cell in the same row

I need some help for my problem. I have a table with e.g. a double column and a string column. If the value in the double column is negativ, the string should be "negativ". And the other way if the value is positiv, the string should be "positiv".
The problem is now if I edit the double value in the jTable, the string should also be updated.
Update to my question, the actual code look like this:
But it doesn't work, because the string in the second column wont be updated after I edit the first column value. It only works when I start the program the first time.
import java.util.Vector;
import javax.swing.*;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.*;
public class ExampleRemoveAddRows extends JFrame {
private Object[] columnNames = {"Double", "positiv / negativ"};
private Object[][] data = {
{new Double(10.0), "positiv"},
{new Double(-10.0), "negativ"},
{new Double(20.0), "positiv"},
{new Double(-30.0), "negativ"}
};
private JTable table;
private DefaultTableModel model;
public ExampleRemoveAddRows() {
model = new DefaultTableModel(data, columnNames) {
#Override
public Class getColumnClass(int column) {
return getValueAt(0, column).getClass();
}
#Override
public Object getValueAt(int row, int column) {
if (column == 1) {
double number = Double.parseDouble(this.getValueAt(row, 0).toString());
System.out.println(number);
System.out.println("good");
System.out.println((number < 0) ? "negativ" : "positiv");
return "C: "+ this.getValueAt(row, 0);//((number < 0) ? "negativ" : "positiv");
} else {
return super.getValueAt(row, column);
}
}
};
table = new JTable(model);
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
ExampleRemoveAddRows frame = new ExampleRemoveAddRows();
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
Thanks for your help.
Sam

I've revised your sscce to show the alternate approach suggested here. Note the alternate ways to get a Double constant. I've also re-factored the String constrants.
Addendum: In helpful comments, #kleopatra observes that querying the model directly will always produce the correct result, but a TableModelListener will only see changes to column 0, not column 1. The simple expedient is to make column 1 non-editable, as its value depends completely on column 0.
#Override
public boolean isCellEditable(int row, int col) {
return col == 0;
}
The first example below uses DefaultTableModel:
import javax.swing.*;
import javax.swing.table.*;
/** #see https://stackoverflow.com/a/13628183/230513 */
public class ExampleRemoveAddRows extends JFrame {
public static final String NEGATIVE = "negativ";
public static final String POSITIVE = "positiv";
private Object[] columnNames = {"Double", POSITIVE + " / " + NEGATIVE};
private Object[][] data = {
{10d, null},
{-10.0, null},
{Double.valueOf(30), null},
{Double.valueOf("-30"), null}
};
private JTable table;
private DefaultTableModel model;
public ExampleRemoveAddRows() {
model = new DefaultTableModel(data, columnNames) {
#Override
public Class getColumnClass(int column) {
return getValueAt(0, column).getClass();
}
#Override
public boolean isCellEditable(int row, int col) {
return col == 0;
}
#Override
public Object getValueAt(int row, int col) {
if (col == 1) {
double number = (Double) this.getValueAt(row, 0);
return (number < 0) ? NEGATIVE : POSITIVE;
} else {
return super.getValueAt(row, col);
}
}
#Override
public void setValueAt(Object aValue, int row, int col) {
super.setValueAt(aValue, row, col);
fireTableCellUpdated(row, 1); // may have changed
}
};
table = new JTable(model);
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
ExampleRemoveAddRows frame = new ExampleRemoveAddRows();
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
This variation extends AbstractTableModel:
import java.awt.EventQueue;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
import javax.swing.table.*;
/**
* #see https://stackoverflow.com/a/13628183/230513
*/
public class ExampleRemoveAddRows extends JFrame {
public static final String NEGATIVE = "negativ";
public static final String POSITIVE = "positiv";
public ExampleRemoveAddRows() {
DoubleModel model = new DoubleModel();
model.add(10.1);
model.add(-10.2);
model.add(Double.valueOf(30.1));
model.add(Double.valueOf("-30.2"));
JTable table = new JTable(model);
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
ExampleRemoveAddRows frame = new ExampleRemoveAddRows();
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private class DoubleModel extends AbstractTableModel {
List<Double> data = new ArrayList<Double>();
public void add(Double d) {
data.add(d);
}
#Override
public int getRowCount() {
return data.size();
}
#Override
public int getColumnCount() {
return 2;
}
#Override
public String getColumnName(int col) {
if (col == 0) {
return "Double";
} else {
return POSITIVE + " / " + NEGATIVE;
}
}
#Override
public Class<?> getColumnClass(int col) {
if (col == 0) {
return Double.class;
} else {
return String.class;
}
}
#Override
public boolean isCellEditable(int row, int col) {
return col == 0;
}
#Override
public Object getValueAt(int row, int col) {
if (col == 0) {
return data.get(row);
} else {
double number = (Double) this.getValueAt(row, 0);
return (number < 0) ? NEGATIVE : POSITIVE;
}
}
#Override
public void setValueAt(Object aValue, int row, int col) {
if (col == 0) {
data.set(row, (Double) aValue);
fireTableRowsUpdated(row, row);
}
}
}
}

You do indeed have access to the TableModel, if I'm not mistaken, through TableModelEvent.getSource().
Just to provide a basic example (mostly because the one sentance answer hardly seems like much of an answer):
TableModel model = (TableModel)te.getSource();
Double number = model.getValueAt(te.firstRow, 0);
model.setValueAt(((number < 0) ? "negativ":"positiv"), te.firstRow, 1);

Converting selected items on a Table model to an object

I have Components I have created that are being put into a table model with two columns as below.
if (!newAcList.isEmpty()) {
for (Acronym acc : newAcList) {
tableModel.addRow(new String[]{acc.getName(), acc.getDefinition()});
}
}
What I need is when the user selects an item on the table model it converts the item back to my Acronym Object. I am using a Listselectionevent Listener.
Here is valueChanged selection event``
#Override
public void valueChanged(ListSelectionEvent e) {
String selectedAcData = null;
String selectDefData = null;
int[] selectedRow = accTable.getSelectedRows();
int[] selectedColumns = accTable.getSelectedColumns();
for (int i = 0; i < selectedRow.length; i++) {
// for (int j = 0; j < selectedColumns.length; j++) {
selectedAcData = (String) accTable.getValueAt(selectedRow[i], 0);
}
}

You might want to create a class that implements the TableModel interface for the acronyms. It might be called AcronymTableModel and is backed by a List<Acronym> list of Acronyms. Then give this model to your table.
The call to accTable.getValueAt(selectedRow[i], 0); in your valueChanged method will then return an instance of an Acronym.
Here's a quick example.
public class Example {
public static void main(String [] a) {
JFrame f = new JFrame();
JPanel p = new JPanel();
List<Acronym> acronyms = new ArrayList<Acronym>();
acronyms.add(new Acronym("FBI", "Federal Bureau of Investigation"));
acronyms.add(new Acronym("CIA", "Central Intelligence Agency"));
final TableModel tModel = new AcronymTableModel(acronyms);
JTable t = new JTable(tModel);
t.getSelectionModel().addListSelectionListener(new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
Acronym a = (Acronym)tModel.getValueAt(e.getFirstIndex(), 0);
System.out.println(a.acronym + ": " + a.definition);
}});
p.add(t);
f.getContentPane().add(p);
f.pack();
f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
f.setVisible(true);
}
}
class Acronym {
String acronym;
String definition;
public Acronym(String a, String d) {
acronym = a;
definition = d;
}
}
class AcronymTableModel implements TableModel {
private List<Acronym> acronyms;
public AcronymTableModel(List<Acronym> acs) {
this.acronyms = new ArrayList<Acronym>(acs);
}
#Override
public int getRowCount() {
return this.acronyms.size();
}
#Override
public int getColumnCount() {
return 2;
}
#Override
public String getColumnName(int columnIndex) {
switch(columnIndex) {
case 0:
return "Acronym";
case 1:
return "Definition";
}
return null;
}
#Override
public Class<?> getColumnClass(int columnIndex) {
return String.class; // Since both columns are simply
}
#Override
public boolean isCellEditable(int rowIndex, int columnIndex) {
return false;
}
#Override
public Object getValueAt(int rowIndex, int columnIndex) {
return acronyms.get(rowIndex);
}
#Override
public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
}
#Override
public void addTableModelListener(TableModelListener l) {
}
#Override
public void removeTableModelListener(TableModelListener l) {
}
}
The Java tutorials are always good and have good examples.
http://docs.oracle.com/javase/tutorial/uiswing/events/listselectionlistener.html

Column name not updating in JTable

I have a JTable for which I have made a table model. But on passing the column names to table model, it is not updating the column names. Can someone tell me why?
class MyTableModelTwo extends AbstractTableModel {
private Object[][] data;
private String[] columnNames = {"Name", "ID Number", "CGPA"};
public MyTableModelTwo(Object[][] data) {
this.data = data;
}
#Override
public int getRowCount() {
return data.length;
}
#Override
public int getColumnCount() {
return columnNames.length;
}
#Override
public Object getValueAt(int rowIndex, int columnIndex) {
return data[rowIndex][columnIndex];
}
#Override
public Class getColumnClass(int c) {
return getValueAt(0, c).getClass();
}
#Override
public boolean isCellEditable(int rowIndes, int columnIndex) {
return false;
}
#Override
public void setValueAt(Object value, int rowIndex, int columnIndex) {
data[rowIndex][columnIndex] = value;
fireTableCellUpdated(rowIndex, columnIndex);
}
}
class MyTableTwo extends JPanel implements TableModelListener {
private JTable table;
private Object[][] data;
private JTextField t;
public MyTableTwo() {
data = new Object[3][3];
t = new JTextField();
for (int i = 0; i < noElements; i++) {
data[i][0] = "Kaushik";
data[i][1] = "2008A3";
data[i][2] = "7.79";
}
MyTableModelTwo m = new MyTableModelTwo(data);
table = new JTable(m);
}
#Override
public void tableChanged(TableModelEvent e) {
int row = table.getRowCount();
double sum = 0, d = 0;
for (int i = 0; i < row; i++) {
double c = (Double) table.getValueAt(i, 16);
sum += c;
}
t.setText("" + sum);
t.setHorizontalAlignment(JTextField.RIGHT);
}
}

You need to override getColumnName(int index) in your TableModel.
#Override
public String getColumnName(int index) {
return columnNames[index];
}