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Disable JTableHeader update after row sorting

I customized a Jtable headers with a TableCellRenderer so filter icon would appear, and as the user clicks on the filter icon, a pop-up filter like excel's appears (picture 1). However, if the user clicks on the text of the header, a row sorter is appliead. When the row sorter is applied (picture 2), it override the customization and filter icon disappears. Is there a way to avoid this behavior while keeping the row sorter on the table header?

You can do this by decorating the original renderer of the table header with a custom one which will add the desired icon of filtering.
For example, follows some code to preserve the sort icons while adding your own label next to the original column header:
import java.awt.Color;
import java.awt.Component;
import java.awt.FlowLayout;
import java.util.Objects;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
public class Main {
private static class MyTableCellRenderer extends DefaultTableCellRenderer {
private final TableCellRenderer originalRenderer;
public MyTableCellRenderer(final TableCellRenderer originalRenderer) {
this.originalRenderer = Objects.requireNonNull(originalRenderer);
}
#Override
public Component getTableCellRendererComponent(final JTable table,
final Object value,
final boolean isSelected,
final boolean hasFocus,
final int row,
final int column) {
final Component original = originalRenderer.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
if (row >= 0) //The header will have a row equal to -1.
return original;
final JPanel container = new JPanel(new FlowLayout(FlowLayout.CENTER, 10, 0));
final JLabel filtering = new JLabel("Filter", JLabel.CENTER); //Your icon should go in this label...
//Put some fancy background to make the positioning of the label clear:
filtering.setOpaque(true);
filtering.setBackground(Color.CYAN);
//The default renderer comes with a border... Let's apply the border to the whole new container:
if (original instanceof JComponent) {
container.setBorder(((JComponent) original).getBorder());
((JComponent) original).setBorder(null);
}
container.add(filtering);
container.add(original);
return container;
}
}
private static void createAndShowGUI() {
final JTable table = new JTable(new Object[][] {
new Object[]{"Data001", "Data002", "Data003"},
new Object[]{"Data011", "Data012", "Data013"},
new Object[]{"Data021", "Data022", "Data023"},
new Object[]{"Data031", "Data032", "Data033"},
new Object[]{"Data041", "Data042", "Data043"}
}, new Object[] {"Column1", "Column2", "Column3"});
table.setAutoCreateRowSorter(true);
final JTableHeader header = table.getTableHeader();
header.setDefaultRenderer(new MyTableCellRenderer(header.getDefaultRenderer()));
final JFrame frame = new JFrame("Table header");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new JScrollPane(table));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(final String[] args) {
SwingUtilities.invokeLater(Main::createAndShowGUI);
}
}
Instead of the word Filter (which appears on each column header) you can use your icons on the created label instead.
References:
Source (see the section: 3. Keeping sort icons).
How can I put a control in the JTableHeader of a JTable?

Possible to detect double click on a JComboBox item?

I have a question for school that states I should change the background color of my JFrame when "an item in the JComboBox is double clicked".
Is this possible using an ItemListener or ActionListener? Or would I need to implement using a MouseListener?
Code:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JComboBox;
import javax.swing.JFrame;
public class ColorSelection extends JFrame {
String[] colorNames = {
"Black", "Blue"
};
Color colors[] = {
Color.BLACK, Color.BLUE
};
JComboBox coloursComboBox = new JComboBox(colorNames);
ColorItemListener colorItemListener = new ColorItemListener(this);
public ColorSelection() {
super("My color combobox");
coloursComboBox.addItemListener(colorItemListener);
add(coloursComboBox, BorderLayout.NORTH);
setSize(600, 600);
setVisible(true);
}
public class ColorItemListener implements ItemListener {
ColorSelection colorSelection;
public ColorItemListener(ColorSelection colorSelection) {
this.colorSelection = colorSelection;
}
#Override
public void itemStateChanged(ItemEvent e) {
if (e.getStateChange() == ItemEvent.SELECTED) {
if (e.getItem().toString().equals("Black")) {
colorSelection.getContentPane().setBackground(Color.BLACK);
} else {
colorSelection.getContentPane().setBackground(Color.BLUE);
}
}
}
}
public static void main(String[] args) {
new ColorSelection();
}
}

Don't know if it is possible because the popup of the checkbox is closed after a single mouse click.
However, if it is possible, I would suggest you would need to add a MouseListener to the JList that has been added to the popup of the combo box.
After creating the combo box you can add a MouseListener to the JList with code like:
JComboBox comboBox = new JComboBox(...);
Object child = comboBox.getAccessibleContext().getAccessibleChild(0);
if (child instanceof BasicComboPopup)
{
BasicComboPopup popup = (BasicComboPopup)child;
JList list = popup.getList();
list.addMouseListener(...);
}

Paint Component seems to be causing cursor and Mouse Listener of Label to not work

Using LayerUI to add labels to the upper corner of a tabbed pane. Would like to allow these labels to display as hyperlinks, so I set the color blue, the cursor to a hand and I added a mouselistener.
Howev,er when I paint the component the cursor customization and mouse listener are not not working.
sample image
Sample Application:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Cursor;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.BorderFactory;
import javax.swing.JComponent;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JLayer;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.SwingUtilities;
import javax.swing.plaf.LayerUI;
public class TopRightCornerLabelLayerUITest {
public static JPanel makeUI() {
JPanel resultPanel = new JPanel();
resultPanel.setLayout( new BorderLayout());
resultPanel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.add("Tab 1", new JPanel());
tabbedPane.add("Tab 2", new JPanel());
resultPanel.add(new JLayer<JComponent>(tabbedPane, new TopRightCornerLabelLayerUI()), BorderLayout.CENTER);
return resultPanel;
}
private static void initandShow()
{
JDialog dialog = new JDialog();
dialog.getContentPane().add(makeUI());
dialog.setSize(520, 240);
dialog.setLocationRelativeTo(null);
dialog.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
initandShow();
}
});
}
}
class TopRightCornerLabelLayerUI extends LayerUI<JComponent> {
private JPanel rubberStamp = new JPanel();
#Override public void paint(Graphics g, JComponent c) {
super.paint(g, c);
JLabel layoutHyperlink = new JLabel("<html><a href=''>File Layout and Descriptions</a></html>");
JLabel templateHyperlink = new JLabel("<html><a href=''>Download Template</a></html>");
layoutHyperlink.setForeground(Color.BLUE.darker());
layoutHyperlink.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
layoutHyperlink.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
// the user clicks on the label
System.err.println("clicked");
}
});
templateHyperlink.setForeground(Color.BLUE.darker());
templateHyperlink.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
templateHyperlink.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
// the user clicks on the label
System.err.println("clicked");
}
});
// Add components
Dimension templateDimension = templateHyperlink.getPreferredSize();
int x = c.getWidth() - templateDimension.width - 5;
SwingUtilities.paintComponent(g, templateHyperlink, rubberStamp, x, 2, templateDimension.width , templateDimension.height);
Dimension layoutDimension = layoutHyperlink.getPreferredSize();
x = c.getWidth() - layoutDimension.width - 15 - templateDimension.width;
SwingUtilities.paintComponent(g, layoutHyperlink, rubberStamp, x, 2, layoutDimension.width, templateDimension.height);
}
}

I was actually unaware of class JLayer until I read your question. I don't have a complete answer but I think it's enough to give you a push in the right direction. I was helped by the lesson in Oracle's Java tutorial: How to Decorate Components with the JLayer Class. That lesson has a section entitled Responding to Events which helped me to figure out how to partially solve your issue. Basically you are just painting the labels and not actually adding them as components and therefore they will not respond to mouse events. Since the labels can be considered part of the JLayer component that is added as a component, you can configure that JLayer to respond to mouse events. As stated in the tutorial lesson, you need to override some other methods in your TopRightCornerLabelLayerUI class. The code below contains two of those methods. Add them to your code and see if they give you the expected result.
public void installUI(JComponent c) {
super.installUI(c);
((JLayer<?>) c).setLayerEventMask(AWTEvent.MOUSE_EVENT_MASK);
}
protected void processMouseEvent(MouseEvent e, JLayer l) {
if (e.getID() == MouseEvent.MOUSE_CLICKED) {
Point pt = e.getPoint();
if (pt.x >= xTemplateHyperlink && pt.x <= (xTemplateHyperlink + widthTemplateHyperlink)) {
System.out.println("clicked");
}
}
}
EDIT:
Forgot to mention that I added the following members to your TopRightCornerLabelLayerUI class...
private int xTemplateHyperlink;
private int yTemplateHyperlink;
private int widthTemplateHyperlink;
private int heightTemplateHyperlink;
And set their values in method paint() like so...
Dimension templateDimension = templateHyperlink.getPreferredSize();
xTemplateHyperlink = c.getWidth() - templateDimension.width - 5;
yTemplateHyperlink = 2;
widthTemplateHyperlink = templateDimension.width;
heightTemplateHyperlink = templateDimension.height;
which explains the code in method processMouseEvent().

Using ListCellRenderers on selected entries

I'm using a ListCellRenderer to edit the appearance of entries in a JList. Once they are selected (by clicking them, this code is within a click event) I call the ListCellRenderer to change the color of the text. If they are selected again I want the text to return to the normal color. The problem I am having is that once I select a second entry the first entry goes back to its normal color. How can I keep selected entries the selected color until they are actually deselected? Here is the section where I actually call the function:
for(int i = 0; i < selectedEntries.size() - 1; i++){
System.out.println("Inside the for loop at entry:" + i);
if(selectedEntries.get(i).equals(selectedEntry)){
selectedEntries.remove(i);
removed = true;
renderer.getListCellRendererComponent(logEntries, value, index, false, false);
System.out.println("Duplicate Entry Removed From List");
}
}
if(!removed){
selectedEntries.add(selectedEntry);
renderer.getListCellRendererComponent(logEntries, value, index, true, false);
}
Just for ease of interpretation selectedEntries is an ArrayList containing each selected entry's text.

Once they are selected (by clicking them, this code is within a click event) I call the ListCellRenderer to change the color of the text
No, that's not how it should work, the ListCellRenderer will be called again (by the JList) and the isSelected parameter will be true, to which you would render the values differently
The ListCellRenderer is responsible for rendering the entire state, selected or not selected.
Have a look at Writing a Custom Cell Renderer for more details
For example
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Font;
import javax.swing.DefaultListCellRenderer;
import javax.swing.DefaultListModel;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new BorderLayout());
DefaultListModel<String> model = new DefaultListModel<>();
model.addElement("Apples");
model.addElement("Bananas");
model.addElement("Peachs");
model.addElement("Pears");
JList<String> listOfStrings = new JList<>(model);
listOfStrings.setCellRenderer(new FancyPancyListCellRenderer());
add(new JScrollPane(listOfStrings));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
public static class FancyPancyListCellRenderer extends DefaultListCellRenderer {
protected static final Font SELECTED_FONT = new Font("Comic Sans MS", Font.PLAIN, 12);
#Override
public Component getListCellRendererComponent(JList<?> list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus);
if (isSelected) {
setForeground(Color.YELLOW);
setFont(SELECTED_FONT);
} else {
setFont(UIManager.getFont("Label.font"));
}
return this;
}
}
}
Also, MouseListener really isn't a suitable means by which to detect changes in the selection, what happens if the user selects rows using the keyboard? You should be using a ListSelectionListener instead (but not to correct this issue).
Have a look at How to Write a List Selection Listener and How to Use Lists for more details

Start editing in a cell in JTable on gaining focus

I have defined cell editors for the two columns in my table in the following manner:
Java Code:
JComboBox combo = new JComboBox();
//code to add items to the combo box goes here.
JTextField textField = new JTextField();
textField.setHorizontalAlignment(JTextField.RIGHT);
TableColumn column = myJTable.getColumnModel().getColumn(0);
column.setCellEditor(new DefaultCellEditor(combo));
column = myJTable.getColumnModel().getColumn(1);
column.setCellEditor(new DefaultCellEditor(textField));
The problem I am facing is that when a focus is moved to a table cell, the cell doesn't become automatically editable. So, when the focus is moved to column 2 (that has a text field as an editor), the caret sign doesn't not appear unless the cell is double-clicked or the user starts typing. Similar is the case for column 1 (that has a combo box as an editor) as here the combo box doesn't appear unless the cell is clicked. These behaviors are counter-intuitive and undesirable for a user operating with the keyboard.:(
Please suggest pointers on how this could be resolved.
Thanks in advance.

This example overrides editCellAt() in a JTable having a DefaultCellEditor using JTextField.
You can bind the Space key to the startEditing action defined for JTable:
table.getInputMap().put(
KeyStroke.getKeyStroke(KeyEvent.VK_SPACE, 0), "startEditing");

As commented above, you can use JComboBox both as renderer and editor. Below is a very basic example. It also shows DefaultCellEditor.setClickCountToStart() usage.
import java.awt.Component;
import javax.swing.DefaultCellEditor;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
public class ComboBoxEditorDemo {
public static void main(String args[]) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("ComboBoxEditorDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTable table = new JTable(
new Object[][] { { "1", "2" }, { "1", "2" } },
new Object[] {"Col1", "Col2" });
table.setRowHeight(24);
TableColumn column = table.getColumnModel().getColumn(1);
column.setCellRenderer(new MyComboBoxRenderer(new String[] { "1", "2", "3" }));
column.setCellEditor(new MyComboBoxEditor(new String[] { "1", "2", "3" }));
DefaultCellEditor editor = new DefaultCellEditor(new JTextField());
editor.setClickCountToStart(1);
column = table.getColumnModel().getColumn(0);
column.setCellEditor(editor);
JScrollPane scrollPane = new JScrollPane(table);
frame.add(scrollPane);
frame.pack();
frame.setVisible(true);
}
static class MyComboBoxRenderer extends JComboBox implements
TableCellRenderer {
public MyComboBoxRenderer(String[] items) {
super(items);
}
public Component getTableCellRendererComponent(JTable table,
Object value, boolean isSelected, boolean hasFocus, int row,
int column) {
if (isSelected) {
setForeground(table.getSelectionForeground());
super.setBackground(table.getSelectionBackground());
} else {
setForeground(table.getForeground());
setBackground(table.getBackground());
}
setSelectedItem(value);
return this;
}
}
static class MyComboBoxEditor extends DefaultCellEditor {
public MyComboBoxEditor(String[] items) {
super(new JComboBox(items));
}
}
}