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How can I call the mouse right click event in SwingGui?

I have a table. If I right-click I got a JPopUpMenu but before the pop-up I want to select the row where the right-click event is done. Here is what I've tried.
path_tbl.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
System.out.println(e.getPoint());
Point point = e.getPoint();
int selectedRow = path_tbl.rowAtPoint(point);
path_tbl.setRowSelectionInterval(selectedRow, selectedRow);
}
});
In that event, I cannot get any output from the console when I right-click. However, when I left-click, points are printed to the console.
java.awt.Point[x=105,y=76]
So, this event only works when I left-click. How can I make this event work with right-click?

Since you want custom mouse behavior, you should not use setComponentPopupMenu.
Instead, display the JPopupMenu yourself, using JPopupMenu’s show method:
JPopupMenu menu = /* ... */;
path_tbl.addMouseListener(new MouseAdapter() {
private void showPopupMenuFor(MouseEvent e) {
if (menu.isPopupTrigger(e)) {
Point point = e.getPoint();
int row = path_tbl.rowAtPoint(point);
if (!path_tbl.isRowSelected(row)) {
path_tbl.setRowSelectionInterval(row, row);
}
menu.show(path_tbl, e.getX(), e.getY());
}
}
#Override
public void mousePressed(MouseEvent e) {
showPopupMenuFor(e);
}
#Override
public void mouseReleased(MouseEvent e) {
showPopupMenuFor(e);
}
#Override
public void mouseClicked(MouseEvent e) {
showPopupMenuFor(e);
}
});
You must check the MouseEvent in both mousePressed and mouseReleased, because exactly when a context menu is triggered depends on the platform and the look-and-feel. (Checking in mouseClicked may or may not be necessary, but it doesn’t hurt.)

In most cases, I'm lazy, so if I don't need to do something, then I'd prefer not to. In this case, I'd prefer to make use of the existing API works as much as possible, meaning, make use of JComponent#setComponentPopupMenu, as it will take care of the "how" and "when" the popup should be shown, based on the current platform.
However, as you have discovered, by default, JTable will NOT select the row when the user presses the "right" mouse button, for that, you could just continue with your current workflow, but, checking to see if the MouseEvent is actually a "right" click.
Lucky for us, some of the original Swing developers were also "lazy" and they provided us with SwingUtilities.isRightMouseButton, yea 🎉
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.Vector;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableModel;
public final class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new BorderLayout());
DefaultTableModel model = new DefaultTableModel(0, 10);
for (int row = 0; row < 10; row++) {
Vector data = new Vector(10);
for (int col = 0; col < 10; col++) {
String value = row + "x" + ((char) (col + 'A'));
data.add(value);
}
model.addRow(data);
}
JPopupMenu menu = new JPopupMenu();
menu.add("Hello");
menu.add("This looks interesting");
menu.add("I like bi-planes");
JTable table = new JTable(model);
table.setComponentPopupMenu(menu);
table.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
if (SwingUtilities.isRightMouseButton(e)) {
Point point = e.getPoint();
int row = table.rowAtPoint(point);
if (!table.isRowSelected(row)) {
table.setRowSelectionInterval(row, row);
}
}
}
});
add(new JScrollPane(table));
}
}
}

Change background colour on typing certain value (jNumberField)

I am trying to change the background colour of a number field based on the numbers that are typed in. Just like a number field turns red when you type a letter in it. I want it to also change red when you type numbers below 1 and above 7.
I understand that you can do this with a button, but I want it to change when you're typing.
This is my code:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class applet03 extends JApplet {
private JButton bHoeveelheid = new JButton();
private JNumberField nfAantal = new JNumberField();
private JTextArea taLijst = new JTextArea("");
private JScrollPane taLijstScrollPane = new JScrollPane(taLijst);
public void init() {
Container cp = getContentPane();
cp.setLayout(null);
cp.setBounds(0, 0, 442, 478);
bHoeveelheid.setBounds(224, 56, 59, 33);
bHoeveelheid.setMargin(new Insets(2, 2, 2, 2));
bHoeveelheid.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
bHoeveelheid_ActionPerformed(evt);
}
});
cp.add(bHoeveelheid);
nfAantal.setBounds(304, 56, 99, 36);
nfAantal.setText("Vul getal in");
nfAantal.setHorizontalAlignment(SwingConstants.CENTER);
nfAantal.addFocusListener(new FocusAdapter() {
public void focusGained(FocusEvent evt) {
nfAantal_FocusGained(evt);
}
});
nfAantal.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent evt) {
nfAantal_KeyPressed(evt);
}
});
cp.add(nfAantal);
taLijstScrollPane.setBounds(224, 136, 168, 180);
cp.add(taLijstScrollPane);
}
public void bHoeveelheid_ActionPerformed(ActionEvent evt) {
if (nfAantal.getInt() < 1 || nfAantal.getInt() > 7) {
nfAantal.setBackground(Color.RED);
} else {
//some other code (not impotant for now)
}
}
public void nfAantal_FocusGained(FocusEvent evt) {
if (nfAantal.getText().equals("Vul getal in")) {
nfAantal.clear();
}
}
public void nfAantal_KeyPressed(KeyEvent evt) {
if (nfAantal.getInt() < 1 || nfAantal.getInt() > 7) {
nfAantal.setBackground(Color.RED);
} else {
//some other code (not impotant for now)
}
}
}
The button part works, but the KeyEvent not.
And when I run this I keep getting these errors:
Exception in thread "AWT-EventQueue-1" java.lang.NumberFormatException: empty String
But when I do this, it kinda works. I still get the same errors but it works. (By the way not optimal, because it only appends it to the text field every second key pressing.):
public void nfAantal_KeyPressed(KeyEvent evt) {
if (nfAantal.getInt() < 1 || nfAantal.getInt() > 7) {
taLijst.append(nfAantal.getText());
} else {
//some other code (not impotant for now)
}
}
So if someone knows why this doesn't work or knows a better way to accomplish this. Then that would be very appreciated!
(By the way I use Java 1.8)
Edit:
I now have (nfAantal.getText().length() > 0) && (nfAantal.getInt() < 1 || nfAantal.getInt() > 7) in the if statement and that got rid of the errors. (Thanks to #Joe)
But that still doesn't solve my question on how to turn the background red on certain values.
Aditional information about JNumberField:
I think this link has the code that makes up JNumberField and this link contains a download to the .jar file with in there the JNumberField Java file.
Another edit:
I think I found out for myself why it doesn't work with a JNumberfield; in the code it changes the background to white if its value is numeric so only if there is a way to get around this part of the code or change it (which I don't know how to do) my question can be answered for a JNumberField, if this isn't the case then I will use the JFormattedTextField instead.
This is the code that needs to be altered or circumvented:
protected void processKeyEvent(KeyEvent e) {
super.processKeyEvent(e);
if (isNumeric() || getText().equals("-") ||
getText().equals("") || getText().equals("."))
setBackground(Color.white);
else
setBackground(Color.red);
}

I don't know what a JNumberField is. It's not part of the JDK and when I searched with Google, it turned up several different ones.
I also don't understand why you are writing an applet.
Therefore, the below code may not be appropriate since it is a stand-alone Swing application that uses JFormattedTextField and DocumentListener.
Explanations after the code.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.text.NumberFormat;
import javax.swing.JFormattedTextField;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.NumberFormatter;
public class RedNumbr implements DocumentListener, Runnable {
private JFormattedTextField aantal;
private JFrame frame;
#Override
public void insertUpdate(DocumentEvent event) {
handleDocumentEvent(event);
}
#Override
public void removeUpdate(DocumentEvent event) {
handleDocumentEvent(event);
}
#Override
public void changedUpdate(DocumentEvent event) {
// Never called for 'JFormattedTextField'
}
#Override
public void run() {
showGui();
}
private JPanel createNumberPanel() {
JPanel numberPanel = new JPanel();
NumberFormat format = NumberFormat.getIntegerInstance();
NumberFormatter formatter = new NumberFormatter(format);
aantal = new JFormattedTextField(formatter);
aantal.setColumns(10);
Document doc = aantal.getDocument();
doc.addDocumentListener(this);
numberPanel.add(aantal);
return numberPanel;
}
private void handleDocumentEvent(DocumentEvent event) {
Document doc = event.getDocument();
int len = doc.getLength();
if (len > 0) {
try {
String text = doc.getText(0, len);
int number = Integer.parseInt(text);
Color fg;
if (number < 1 || number > 7) {
fg = Color.red;
}
else {
fg = UIManager.getColor("TextField.foreground");
}
aantal.setForeground(fg);
}
catch (BadLocationException | NumberFormatException x) {
// Ignore.
}
}
}
private void showGui() {
frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(createNumberPanel(), BorderLayout.CENTER);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new RedNumbr());
}
}
Whenever the contents of the JFormattedTextField are changed, the relevant DocumentListener method is invoked. In those methods I check whether the JFormattedTextField contains a number and if it does then I change the foreground color of the JFormattedTextField according to your conditions, i.e. if the number is less than one (1) or greater than 7 (seven).
Note that the NumberFormatter does not prevent entering non-digits because JFormattedTextField handles that when it loses focus. Nonetheless it handles entering positive and negative numbers, which saves you some work. And the point of my answer is simply to demonstrate how to change the foreground color based on the entered text, which I believe answers your question.
EDIT
In order to change the background of the JFormattedTextField, rather than the foreground, you just need to change two lines in my code, above.
Replace
fg = UIManager.getColor("TextField.foreground");
with
fg = UIManager.getColor("TextField.background");
and also replace
aantal.setForeground(fg);
with
aantal.setBackground(fg);

I suppose that the JNumberField is an extension of JTextField and if it is the case it could be the synchronization problem between the main thread and the thread that is triggered by the KeyEvent action. To make sure that the event thread will be carried out you code it with invokeLater.
public void nfAantal_KeyPressed(KeyEvent evt) {
if (nfAantal.getText().length() > 0) && (nfAantal.getInt() < 1 || nfAantal.getInt() > 7) {
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
nfAantal.setBackground(Color.RED);
}
});
} else {
//some other code (not impotant for now)
}
}

reading the value of jtable selected row

I am working with java RMI and swing and I have read the values from database but i am unable to read the value of selected row in this code. What i want to JTable to show all databases and it is showing all the available databases in server but i am unable to read the selected row value in this
package schoolclient;
import javax.swing.*;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.table.*;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.*;
import schoolserver.SchoolInterface;
public class DatabaseList {
JFrame jFrame = null;
JPanel jPanel = null;
JList jList = null;
JTable jTable = null;
String data = null;
schoolserver.SchoolInterface schoolInt = null;
public DatabaseList(SchoolInterface sii) {
schoolInt = sii;
jFrame = new JFrame();
jTable = new JTable(){
public boolean isCellEditable(int row, int column) {
return false;
}
};
jTable.setModel(createTable());
jTable.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
jTable.addMouseListener(new MouseAdapter() {
public void MouseClicked(MouseEvent e) {
if(SwingUtilities.isLeftMouseButton(e) && (e.getClickCount() == 2)) {
new createListSelection();
}
}
});
JScrollPane scrollPane = new JScrollPane(jTable);
jFrame.add(scrollPane);
jFrame.setSize(200, 200);
jFrame.setVisible(true);
}
private DefaultTableModel createTable() {
DefaultTableModel dtm = new DefaultTableModel();
dtm.addColumn("Databases", createArray());
return dtm;
}
private class createListSelection implements ListSelectionListener {
#Override
public void valueChanged(ListSelectionEvent e) {
if(!e.getValueIsAdjusting()) {
ListSelectionModel lsm = jTable.getSelectionModel();
data = (String) jTable.getValueAt(jTable.getSelectedRow(), 0);
System.out.println(data);
}
}
}
Object[] createArray() {
ArrayList<Object> al = null;
Object[] x = null;
try {
al = schoolInt.availableDatabases();
x = new Object[al.size()];
int i = 0;
for(Object o : schoolInt.availableDatabases())
x[i++] = o;
}
catch(Exception e) {
JOptionPane.showMessageDialog(null, "no connection to database or "
+ "remote server availabe", "Server Information", JOptionPane.OK_OPTION);
}
return x;
}
}

You look to be over-complicating things. Don't re-add listeners within a listener, but rather simply add one listener, a MouseListener to the JTable, and add it once. Within it check for double clicks (presses) and respond. Something like:
jTable.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
if (e.getButton() == MouseEvent.BUTTON1 && e.getClickCount() == 2) {
data = (String) jTable.getValueAt(jTable.getSelectedRow(), 0);
System.out.println(data);
}
}
});
Other problems, your method within your MouseAdapter will never be called, ever:
jTable.addMouseListener(new MouseAdapter() {
public void MouseClicked(MouseEvent e) {
// ....
}
});
Your capitalization is wrong, and since MouseAdapter/MouseListener does not have a MouseClicked method (it is mouseClicked) this method is never called. Always place an #Override annotation above any method that you think might be an override, and let the compiler warn you if it is not so. Had you done this, you'd get a prompt warning from the compiler.
Regarding your comment
You never add a selection listener to the JTable. Again the method within the MouseAdapter is never called since it is not capitalized correctly
Even if it did get called, what use is there repeatedly adding a ListSelectionListener?
If your goal is to only respond to double-clicks, a ListSelectionListener is not what you want. Only a MouseListener would work in this situation.
Do read the appropriate tutorials as they explain all of this and well. Please check out the links to be found within the Swing Info tag.

Detect CTRL+V in Swing App but keep original function

Wrting a chat application, I want the user to be able to send images out of his/her clipboard. For this, I would like to catch any CTRL+Vkeyboard input. Since pasting text should be possible as by default, the original ctrl+v-function (pasting text) must not be overridden.
I see can two approaches, of which none works for me:
1st: Taken from the official Java documentation: KEY LISTENER
editorPane.addKeyListener(new KeyListener() {
#Override
public void keyPressed(KeyEvent e) {
e.getKeyChar()
// when I press ctrl+v, ^ this is falsely a white square character, looks like (U+25A1). Plain v without ctrl does work.
e.getKeyCode()
// ^ this is falsely 0
// (e.getModifiersEx() correctly returns InputEvent.CTRL_DOWN_MASK)
}
2nd: KEY BINDING
InputMap iMap = editorPane.getInputMap(condition);
ActionMap aMap = editorPane.getActionMap();
iMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_V, InputEvent.CTRL_DOWN_MASK), "ctrlV");
aMap.put("ctrlV", new AbstractAction() {
#Override
public void actionPerformed(ActionEvent e) {
// works, but overrides natural ctrl+v function!
}
});
Any ideas?
Note: I am using a "foreign" keyboard layout (German). But I can't see why this should make any difference - I would pretty much like to have my application work internationally.
Cheers
edit. Alt+SomeKey however is correctly recognized by the KeyListener
edit2. after changing keyboard layout to US, problem persists.

Stick to Keybindings: KeyListener is a low-level API, while Keybindings will provide you consistent, predictable and robust behaviour.
The solution here is quite easy. You can simply combine the actions yourself by adding a CombinedAction class that will execute the "original" action bound to CTRL+V and the "custom" action you want to execute.
See a small example below combining both actions (here my custom action is a Sysout):
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JComponent;
import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.KeyStroke;
import javax.swing.ScrollPaneConstants;
public class TestEditorPane {
private JEditorPane editorPane;
public static class CombinedAction implements ActionListener {
private final ActionListener action1;
private final ActionListener action2;
public CombinedAction(ActionListener action1, ActionListener action2) {
super();
this.action1 = action1;
this.action2 = action2;
}
#Override
public void actionPerformed(ActionEvent e) {
if (action1 != null) {
action1.actionPerformed(e);
}
if (action2 != null) {
action2.actionPerformed(e);
}
}
}
public TestEditorPane() {
}
private void initUI() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// JTEXTBOX
editorPane = new JEditorPane();
KeyStroke ctrlV = KeyStroke.getKeyStroke(KeyEvent.VK_V, KeyEvent.CTRL_DOWN_MASK);
final ActionListener ctrlVAction = editorPane.getActionForKeyStroke(ctrlV);
editorPane.registerKeyboardAction(new CombinedAction(ctrlVAction, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("This is my action on CTRL+V");
}
}), ctrlV, JComponent.WHEN_FOCUSED);
// JSCROLLPANE
JScrollPane scroll1 = new JScrollPane(editorPane);
scroll1.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
scroll1.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
frame.add(scroll1);
frame.setSize(400, 400);
frame.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
TestEditorPane test = new TestEditorPane();
test.initUI();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
}

ListSelectionListener on JList not working

i'm having problems with this listener, the gui in general constructs and works fine, also the jlist is there but when i select some items in the list i dont see the results and also not the printl() i wrote for test purpose, pls note this code is contained within the getJContentPane in order to add the event handler at init-time
private JList myList=new JList(dlm);//a defaultlistmodel
myList.addListSelectionListener(new ListSelectionListener() {
public void valueChanged(ListSelectionEvent evt) {
if (evt.getValueIsAdjusting()){
System.out.println("Eventhandler called");
return;
}
System.out.println("Eventhandler called");
doMyMethod(evt);
}
});
The doMyMethod():
private void doMyMethod(ListSelectionEvent e){
if(e.getValueIsAdjusting()){
return;
}else{
String item=(String)e.getSource();
accounter.add(item);
}
}
It is a very simple method which takes as parameter an instance of ListSelectionEvent
The main problem in my opinion is not the doMyMethod() which performs very basic actions but the fact that the eventHandler is not fired at all, it seems lik the gui does not "listen" to this list at all
Any idea?
here the initialisation code:
private JScrollPane getScrollBox() {
if (scrollboxBox == null) {
scrollboxBox = new JScrollPane();
scrollBox.setBounds(new Rectangle(280, 56, 245, 204));
scrollBox.getViewport().add(myList,null);
myList.addListSelectionListener(new ListSelectionListener() {
public void valueChanged(ListSelectionEvent evt) {
System.out.println("addListSelectionListener");
if (evt.getValueIsAdjusting()){
System.out.println("Eventhandler called");
return;
}
System.out.println("Eventhandler called");
doMyMethod(evt);
}
});
}
return scrollboxBox;
}

After trying to understand what is going on in your question I understood that you are failing to get selected item in the list, when the selection is changed.
To present you how this could be achieved I have built the below example. You can observe there when each part of the if else is called. The if(e.getValueIsAdjusting()) is execute always when you drag the moue over items. The else part is called when you release the mouse while previously clicked on an item.
There are some serious issues in the code that you have provided, therefore I tried to remove all that is unnecessary, e.g.
1.The doMyMethod() method and the if(e.getValueIsAdjusting()) piece of code that is in it would never be called since you already are checking that condition before it is called. Plus there is no need to code a method working on listener's events, this code should stay inside the listener which is private. Then if you want to call programmatically its code you would call the listener.valueChanged(evt).
2.The evt.getSource() returns the object which is author of the event in this case the myList not the selected item which I think you were after, for this use the getSelectedValue() on the source or myList directly since this listener serves only this list.
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
public class ListTest extends JPanel
{
private JScrollPane myScrollPane;
private JList myList;
private ListSelectionListener lSL = new ListSelectionListener()
{
#Override
public void valueChanged(ListSelectionEvent evt)
{
if(evt.getValueIsAdjusting())
{
System.out.println("Eventhandler called evt.getValueIsAdjusting() true");
return;
}
else
{
// String item = (String) evt.getSource();//!!!Exception casting JList to String
//maybe what you need is getSelectedValue()
System.out.println("else called myList.getSelectedValue() ="+myList.getSelectedValue());
}
}
};
private ListTest()
{
int noRows = 25;
Object[] listData = new String[noRows];
for(int i =0; i < noRows; i++)
listData[i]= "Oi "+i;
this.myList = new JList(listData);
this.myScrollPane = new JScrollPane(myList);
myList.addListSelectionListener(lSL);
add(myScrollPane);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
#Override
public void run()
{
ListTest p = new ListTest();
JPanel contentPane = new JPanel();
contentPane.add(p);
JFrame f = new JFrame();
f.setContentPane(contentPane);
f.setSize(800, 600);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
});
}
}
Hope that even if it doesn't solve your problem it at least will be helpful in building an SSCCE for us.