Develop Reference

JFrame opening empty

I'm trying to create a program and it's not showing anything in JFrame which is rather odd. The code seems to fit but java appears to be confused or something. Here's my code so far:
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.io.IOException;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class Img extends JFrame{
/**
*
*/
private static final long serialVersionUID = -6362332275268668673L;
static JFrame panel = new JFrame();
private JButton next= new JButton("Next");
public Img(String a, String b){
ShowPng1(a,b);
}
public void ShowPng1(String a, String b) {
ImageIcon theImage = new ImageIcon("Icon_Entry_21.png");
panel.setSize(300, 300);
panel.setResizable(false);
JLabel label = new JLabel(a);
JLabel label2 = null;
if(!b.isEmpty()){
label2 = new JLabel("NOTE: " + b);
}
JLabel imageLabel = new JLabel(theImage);
imageLabel.setOpaque(true);
JPanel p1 = new JPanel(new GridLayout(3, 1));
p1.add(imageLabel);
p1.add(label);
if(label2 != null)p1.add(label2);
panel.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.setVisible(true);
}
public void ShowPng2(String a, String b) {
ImageIcon theImage = new ImageIcon("Icon_Entry_21.png");
panel.setSize(300, 300);
panel.setResizable(false);
JLabel label = new JLabel(a);
JLabel label2 = null;
if(!b.isEmpty()){
label2 = new JLabel("NOTE: " + b);
}
JLabel imageLabel = new JLabel(theImage);
imageLabel.setOpaque(true);
JPanel p1 = new JPanel(new GridLayout(3, 1));
p1.add(imageLabel);
p1.add(label);
if(label2 != null)p1.add(label2);
p1.add(next);
panel.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.setVisible(true);
try {
Runtime.getRuntime().exec("cmd /c start mailrugames://play/0.3001");
} catch (IOException e) {
JOptionPane.showMessageDialog(null, "Error launching client.","Error", JOptionPane.ERROR_MESSAGE);
System.exit(-1);
}
}
public void actionPerformed(ActionEvent e) {
try {
ShowPng1("Applying patch NOW.","");
Process p1 = Runtime.getRuntime().exec("cmd /c start Start.bat");
p1.waitFor();
JOptionPane.showMessageDialog(null, "Done!","Note", JOptionPane.INFORMATION_MESSAGE);
System.exit(0);
} catch (IOException e1) {
e1.printStackTrace();
System.exit(-1);
} catch (InterruptedException e1) {
e1.printStackTrace();
System.exit(-1);
}
}
public static void main(String[] args) throws IOException, InterruptedException {
Img i = new Img("Preparing client for a patch","");
Process p1 = Runtime.getRuntime().exec("cmd /c start Clean.bat");
p1.waitFor();
Img.panel.dispose();
i.ShowPng2("Launching client.","Make sure the client is fully patched before closing it and clicking `Next`");
}
}
It should load an Image imageLabel into a container and show some text label and label2 on the bottom. The difference between ShowPng1() and ShowPng2() is the Next button, it's located in ShowPng2().

You add nothing to the JFrame.
You never set the JFrame to visible.
You tie up the Swing event thread with a long-running process.
You need to add components to the JFrame itself.
You need to set it visible after components have been added.
You need to run your long-running process in a background thread.
You need to go through the Swing tutorials.
Check out the swing tag, click on the info link, and check out the resources that it contains.

1) You are not adding components to the JFrame itself. You forget to add
public class Img extends JFrame{
.
.
public void ShowPng1(String a, String b) {
//your code here, don't call panel.setVisible(true) here is not necesary
this.add(panel);
}
}
2) Don't call panel.setVisible(true) it's not necessary.. just call i.setVisible(true) in main.
3)To ensure that your code is running in the event dispatch thread wrap it with SwingUtilities.invokeLater(..)
4)You should execute your command in a background thread if it's a long running task cause if not you will block your gui. Read more in Concurrency in swing
5) Follow Java code conventions, method names starts with lower-case with a camel style.
6) Follow #HovercraftFullOfEels advices too.
Take a look to the Swing Tutorial

JFrame to JApplet doesnt work in browser

I have a Java program with a Swing GUI im trying to make it work as a JApplet on a HTML file when I test it on Eclipse launch it as a Applet it works but when I compile it using javac. I get all these files Reverser.class, Reverser$1.class, Reverser$2.class, Reverser$3.class and Reverser$4.class. It doesnt work an help
<HTML>
<BODY>
<applet code="Reverser.class", height="500" width="800">
</applet>
</BODY>
</HTML>
package Applets;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
public class Reverser extends JApplet
{
/**
*
*/
private static final long serialVersionUID = 1L;
//All Swing elements declared here
private JTextArea userinput, useroutput;
private JScrollPane sbr_userinput, sbr_useroutput;
private JButton runButton, clearButton, homeButton;
private String text; //User input stored here
private String reversed_text; //reversed text stored here
public void init()
{
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
setContentPane(GUI());
}
});
} catch (Exception e) {
System.err.println("createGUI didn't complete successfully");
}
}
public Container GUI() //Main GUI container here
{
JPanel totalGUI = new JPanel(); //Main panel set here
totalGUI.setLayout(new GridLayout(1, 2, 3, 3)); //Main panel layout set here.
JPanel lPanel = new JPanel(); //Left panel made here
lPanel.setLayout(new GridLayout(2, 1, 3 , 3)); //Left panel layout set here
totalGUI.add(lPanel); // Left Panel added to main panel.
JPanel rPanel = new JPanel(new GridLayout(3, 1, 3 , 3)); //Right panel made here and its layout set here aswell
totalGUI.add(rPanel);//Right panel added to main panel.
//Userinput TextArea made here
userinput = new JTextArea("Welcome to wicky waky text reverser!!!" + "\n" + "Enter your sentence HERE man!!!!");
userinput.setEditable(true); //TextArea set to editable
userinput.setLineWrap(true);
userinput.setWrapStyleWord(true);
lPanel.add(userinput);//TextArea added to left panel
useroutput = new JTextArea(); //useroutput TextArea set here
useroutput.setEditable(false); //TextArea set to not editable
useroutput.setLineWrap(true);
useroutput.setWrapStyleWord(true);
lPanel.add(useroutput); //TextArea added to the left panel
//Scroll bar made here
sbr_userinput = new JScrollPane(userinput, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
sbr_userinput.setPreferredSize(new Dimension(300, 300));
lPanel.add(sbr_userinput); //Scroll bar added to left panel
//Scroll bar made here
sbr_useroutput = new JScrollPane(useroutput, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
sbr_useroutput.setPreferredSize(new Dimension(300, 300));
lPanel.add(sbr_useroutput); //Scroll bar added to the left panel
runButton = new JButton("RUN"); //Button made here
runButton.addActionListener(new ActionListener() //Action Listener made here
{
public void actionPerformed(ActionEvent e)
{
text = userinput.getText(); //Get userinput here
reversed_text = reverser(text); //reverser method called here
try {
userinput.setText("");
userinput.setText("Processed");
Thread.sleep(500); //sleep 0.5 sec
//Print out all output here
useroutput.setText("Your sentence is ==> " + text + "\n" + "\n"
+ "Your reversed sentence is ==> " + reversed_text);
} catch (InterruptedException e1)
{
e1.printStackTrace();
}
System.out.println("working");
}
});
rPanel.add(runButton); //Add button to right panel
clearButton = new JButton("CLEAR"); //New button made here
clearButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
userinput.setText(""); //Set userinput to empty
useroutput.setText(""); //Set useroutput to empty
System.out.println("cleared");
}
});
rPanel.add(clearButton); //Add button to right panel
homeButton = new JButton("HOME"); //New button made here
homeButton.addActionListener(new ActionListener() //Action Listener added here
{
public void actionPerformed(ActionEvent e)
{
}
});
rPanel.add(homeButton); //add button to right panel
totalGUI.setOpaque(true);
return totalGUI; // return totalGUI
}
public static String reverser(String text)
{
//"text" is now put in the object "reverse_text", StringBuffer used so I can use the reverse method.
StringBuffer reverse_text = new StringBuffer(text);
String reversed = reverse_text.reverse().toString(); //reverse and toString methods used.
return reversed; // return revered
}
}

You don't have the package name in your applet. Consider changing
code="Reverser.class"
to
code="Applets.Reverser.class"
and making sure that the class file is in the Applets subdirectory relative to the HTML file. Or even better, create a jar file.
Also you need to post the error messages that the browser is giving you. You could have a version incompatibility for all we know.

Add Video Frame to JTabbed pane

I have created a java tabbed pane. In the tabbed pane i have created a tab called Video. I want whenever i click on the video tab a video should automatically be played on the tab panel itself. Can I do this? If yes please tell me how to do it.

You have to add a ChangeListener to your JTabbedPane component and override the stateChanged method:
tabbedPane.addChangeListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent e) {
if (e.getSource() instanceof JTabbedPane) {
JTabbedPane pane = (JTabbedPane) e.getSource();
if (pane.getSelectedIndex() == 2) {
// start playing the media clip in tab 2
mediaPlayer.start();
}
}
}
});
Here is a complete, working code:
package tabvideo;
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.media.CannotRealizeException;
import javax.media.NoPlayerException;
import javax.media.Player;
import javax.media.Manager;
public class TabbedPaneVideoDemo extends JPanel {
Player mediaPlayer = null;
public TabbedPaneVideoDemo() {
super(new GridLayout(1, 1));
JTabbedPane tabbedPane = new JTabbedPane();
ImageIcon icon = createImageIcon("images/icon.gif");
JComponent panel1 = makeTextPanel("Panel #1");
tabbedPane.addTab("Tab 1", icon, panel1, "Does nothing");
tabbedPane.setMnemonicAt(0, KeyEvent.VK_1);
JComponent panel2 = makeTextPanel("Panel #2");
tabbedPane.addTab("Tab 2", icon, panel2, "Does twice as much nothing");
tabbedPane.setMnemonicAt(1, KeyEvent.VK_2);
JComponent panel3 = makeTextPanel("Panel #3");
tabbedPane.addTab("Tab 3", icon, panel3, "Still does nothing");
tabbedPane.setMnemonicAt(2, KeyEvent.VK_3);
JComponent panel4 = makeVideoPanel("somevideo.avi");
tabbedPane.addTab("Tab 4", icon, panel4, "Playes video!");
tabbedPane.setMnemonicAt(3, KeyEvent.VK_4);
tabbedPane.addChangeListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent e) {
if (e.getSource() instanceof JTabbedPane) {
JTabbedPane pane = (JTabbedPane) e.getSource();
if (pane.getSelectedIndex() == 2) {
// start playing the media clip in tab 2
mediaPlayer.start();
}
}
}
});
// Add the tabbed pane to this panel.
add(tabbedPane);
// The following line enables to use scrolling tabs.
tabbedPane.setTabLayoutPolicy(JTabbedPane.SCROLL_TAB_LAYOUT);
}
protected JPanel makeVideoPanel(String filename) {
JPanel panel = new JPanel(false);
panel.setLayout(new BorderLayout()); // use a BorderLayout
// Use lightweight components for Swing compatibility
Manager.setHint(Manager.LIGHTWEIGHT_RENDERER, true);
try {
URL mediaURL = new File(filename).toURI().toURL();
// create a player to play the media specified in the URL
mediaPlayer = Manager.createRealizedPlayer(mediaURL);
// get the components for the video and the playback controls
Component video = mediaPlayer.getVisualComponent();
Component controls = mediaPlayer.getControlPanelComponent();
if (video != null)
panel.add(video, BorderLayout.CENTER); // add video component
if (controls != null)
panel.add(controls, BorderLayout.SOUTH); // add controls
} // end try
catch (NoPlayerException noPlayerException) {
System.err.println("No media player found");
} // end catch
catch (CannotRealizeException cannotRealizeException) {
System.err.println("Could not realize media player");
} // end catch
catch (IOException iOException) {
System.err.println("Error reading from the source");
} // end catch
return panel;
} // end MediaPanel constructor
/** Returns an ImageIcon, or null if the path was invalid. */
protected static ImageIcon createImageIcon(String path) {
java.net.URL imgURL = TabbedPaneVideoDemo.class.getResource(path);
if (imgURL != null) {
return new ImageIcon(imgURL);
} else {
System.err.println("Couldn't find file: " + path);
return null;
}
}
protected JComponent makeTextPanel(String text) {
JPanel panel = new JPanel(false);
JLabel filler = new JLabel(text);
filler.setHorizontalAlignment(JLabel.CENTER);
panel.setLayout(new GridLayout(1, 1));
panel.add(filler);
return panel;
}
/**
* Create the GUI and show it. For thread safety, this method should be
* invoked from the event dispatch thread.
*/
private static void createAndShowGUI() {
// Create and set up the window.
JFrame frame = new JFrame("TabbedPaneDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Add content to the window.
frame.add(new TabbedPaneVideoDemo(), BorderLayout.CENTER);
// Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
// Schedule a job for the event dispatch thread:
// creating and showing this application's GUI.
SwingUtilities.invokeLater(new Runnable() {
public void run() {
// Turn off metal's use of bold fonts
UIManager.put("swing.boldMetal", Boolean.FALSE);
createAndShowGUI();
}
});
}
}

use the JTabbedPane getModel() of type SingleSelectionModel, add a ChangeListener to the model, you'll get an event, when a tab has been selected.

EDIT: Do you mean, it should run automatically w/o any button press, then use the JTabbedPane getModel() of type SingleSelectionModel, add a ChangeListener to the model, you'll get an event, when a tab has been selected.
If you mean it should run inside the small tab, maybe you can run a Thread that displays frames of IconImages.

Swing persistent popup

I need to display a swing popup with my custom component. The popup should stay visible, until I hide it myself, but shouldn't get focus.
I have a code written by some other developer that does it in the following way:
popupMenu = new JPopupMenu();
popupMenu.add(myCustomComponent, BorderLayout.CENTER);
popupMenu.setFocusable(false);
popupMenu.setVisible(true);
popupMenu.show(parentComponent, x, y);
This seems to work, but has a bug - when the popup is visible, first mouse click outside the component is consumed by the popup. So I need to click twice to set focus to another component.
How can I fix it? Or what is correct way to make the popup?
UPDATE
At last I've managed to reproduce my problem in short code fragment. Thanks to Guillaume Polet for giving me a starting point.
Here's the code:
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.*;
public class TestJPopup {
protected void initUI() {
JFrame frame = new JFrame(TestJPopup.class.getSimpleName());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final JTextField textField = new JTextField("Some text field");
frame.add(textField, BorderLayout.WEST);
final JButton buttonToHit = new JButton("Hit me");
buttonToHit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(buttonToHit, "You hit the button successfully");
}
});
frame.add(buttonToHit);
frame.setSize(200, 100);
frame.setVisible(true);
final JPopupMenu popup = new JPopupMenu();
popup.add(new JLabel("<html>Hey!<br>I'm the popup window!</html>"),
BorderLayout.NORTH);
popup.setFocusable(false);
popup.setVisible(true);
popup.show(textField, 60, 60);
// I want to activate popup when user clicks in the text field
textField.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
if (popup != null) {
popup.show(textField, 60, 60);
}
}
});
}
public static void main(String[] args) throws Exception {
Class lnfClass = Class.forName("com.sun.java.swing.plaf.windows.WindowsLookAndFeel", true,
Thread.currentThread().getContextClassLoader());
LookAndFeel feel = (LookAndFeel) lnfClass.newInstance();
UIManager.setLookAndFeel(feel);
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new TestJPopup().initUI();
}
});
}
}
Two critical moments:
Windows look and feel used (with default not reproducible)
Mouse listener attached to text field in main frame

Not an answer, but just an example SSCCE in which I can't currently reproduce the behaviour you described. Maybe start from this code, try to reproduce the error and the edit your post with modified non-working code.
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPopupMenu;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class TestJPopup {
protected void initUI() {
JFrame frame = new JFrame(TestJPopup.class.getSimpleName());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel leftLabel = new JLabel("Left");
frame.add(leftLabel, BorderLayout.WEST);
final JButton buttonToHit = new JButton("Hit me");
buttonToHit.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(buttonToHit, "You hit the button successfully");
}
});
frame.add(buttonToHit);
frame.setSize(500, 400);
frame.setVisible(true);
JPopupMenu popupMenu = new JPopupMenu();
popupMenu.add(new JLabel("<html>A Custom<br>component<br>made to<br> simulate <br>your custom component</html>"),
BorderLayout.NORTH);
JTextField textfield = new JTextField(30);
popupMenu.add(textfield);
popupMenu.setFocusable(false);
popupMenu.setVisible(true);
popupMenu.show(leftLabel, 20, 20);
// Let's force the focus to be in a component in the popupMenu
textfield.requestFocusInWindow();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new TestJPopup().initUI();
}
});
}
}

Not a solution, but:
Looks like a bug to me, even a plain componentPopup exhibits the same mis-behaviour (in winLAF and Nimbus, not in Metal):
JTextField field = new JTextField("some popup owner");
JPopupMenu menu = new JPopupMenu();
menu.add("dummy");
field.setComponentPopupMenu(menu);
Action action = new AbstractAction("hit me!") {
#Override
public void actionPerformed(ActionEvent e) {
LOG.info("got hit!");
}
};
JComponent content = new JPanel();
content.add(new JButton(action));
content.add(field);

for quick research and/or for future readers,
this issue is reproducible and presented for,
a) JPopup
b) JMenu
tested on jdk1.6.0_25 and jdk1.7.0_04,
same issue on WinXp and Win7,
for Look and Feel to SystemLookAndFeel / WindowsLookAndFeel,

Here's a possible workaround with JWindow instead of JPopupMenu, that was proposed by mKorbel in comments:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class TestJPopup {
protected void initUI() {
final JFrame frame = new JFrame(TestJPopup.class.getSimpleName());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final JTextField textField = new JTextField("Some text field");
frame.add(textField, BorderLayout.WEST);
final JButton buttonToHit = new JButton("Hit me");
buttonToHit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(buttonToHit, "You hit the button successfully");
}
});
frame.add(buttonToHit);
frame.setSize(200, 70);
frame.setVisible(true);
final JWindow popup = new JWindow();
popup.getContentPane().add(new JLabel("<html>Hey!<br>I'm the popup window!</html>"),
BorderLayout.NORTH);
popup.setLocation(frame.getLocation().x + 60, frame.getLocation().y + 60);
popup.pack();
popup.setFocusable(false);
popup.setVisible(true);
// I want to activate popup when user clicks in the text field
textField.addMouseListener(new MouseAdapter() {
#Override
public void mouseReleased(MouseEvent e) {
if (popup != null) {
popup.setVisible(true);
popup.setLocation(frame.getLocation().x + 60, frame.getLocation().y + 60);
popup.toFront();
}
}
});
textField.addFocusListener(new FocusAdapter() {
#Override
public void focusLost(FocusEvent e) {
if (popup != null) {
popup.setVisible(false);
}
}
});
}
public static void main(String[] args) throws Exception {
Class lnfClass = Class.forName("com.sun.java.swing.plaf.windows.WindowsLookAndFeel", true,
Thread.currentThread().getContextClassLoader());
LookAndFeel feel = (LookAndFeel) lnfClass.newInstance();
UIManager.setLookAndFeel(feel);
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new TestJPopup().initUI();
}
});
}
}

Here is the magic line that fixes the problem:
UIManager.put("PopupMenu.consumeEventOnClose", Boolean.FALSE);
I found this after looking into the source code for the BasicPopupMenuUI class. Apparently this behaviour is a deliberate design choice according to the following comments in the code, but it sure feels like a bug to me.
// Ask UIManager about should we consume event that closes
// popup. This made to match native apps behaviour.
By the way, it happens in Java 5 and 6 too.

How to force JPopupMenu to show title even if Look and Feel UI dictates otherwise?

Javadoc for JPopupMenu constructor says the following:
JPopupMenu
public JPopupMenu(String label)
Constructs a JPopupMenu with the specified title.
Parameters:
label - the string that a UI **may** use to display as a title for the popup menu.
Key word being "may". Evidently in the default UI, such titles are ignored when creating a popup menu. I very much want such titles in some of my popup menus to be used regardless of whether or not the L&F thinks I should. I can't find the hook to make it so. Evidently, this is buried deep in the UI code somewhere. Is there a way to override this default?
Failing that, I have tried adding a disabled menu item as the first item of the menu. Trouble with that is then I lose control of its rendering, and it renders in the "greyed out" style instead of appearing as the important title. If I don't disable it, then it renders as I want, but is selectable, which a title would not be.
So bottom line, how do I either force the UI to display my title, or failing that, how do I add a non-selectable menu item at the top of the menu that I have full rendering control over?

I had similar problem (I mean the original question). I solved it this way:
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenuItem;
import javax.swing.JPopupMenu;
import javax.swing.SwingConstants;
public class LabeledPopupMenu extends JPopupMenu
{
private String originalLabelText = null;
private final JLabel label;
private static String replaceHTMLEntities(String text)
{
if (-1 != text.indexOf("<") ||
-1 != text.indexOf(">") ||
-1 != text.indexOf("&"))
{
text = text.replaceAll("&", "&");
text = text.replaceAll("<", "<");
text = text.replaceAll(">", ">");
}
return text;
}
public LabeledPopupMenu()
{
super();
this.label = null;
}
public LabeledPopupMenu(String label)
{
super();
originalLabelText = label;
this.label = new JLabel("<html><b>" +
replaceHTMLEntities(label) + "</b></html>");
this.label.setHorizontalAlignment(SwingConstants.CENTER);
add(this.label);
addSeparator();
}
#Override public void setLabel(String text)
{
if (null == label) return;
originalLabelText = text;
label.setText("<html><b>" +
replaceHTMLEntities(text) +
"</b></html>");
}
#Override public String getLabel()
{
return originalLabelText;
}
}
I have tested it ony on Mac with default L&F, but it worked for me:
public static void main(String[] args)
{
JFrame frame = new JFrame();
frame.setSize(100, 100);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocation(100, 100);
frame.setVisible(true);
LabeledPopupMenu myPopup = new LabeledPopupMenu("Say & <something>");
myPopup.add(new JMenuItem("Sample item"));
myPopup.show(frame, 50, 50);
}

JPopup is very strange Container, didn't work me
1) public JPopupMenu(String label)
2) didn't work me alignment for JLabel, please maybe somebody can test text justify by using Html
3) not possible shows JComboBox dropdown popup is same time with JPopup (doesn't matter if is JPopup light or heavyweight)
4) and another (not important for basic Swing) tested Java5 and 6 with various LaF
import java.awt.*;
import javax.swing.*;
import javax.swing.UIManager.LookAndFeelInfo;
import javax.swing.event.*;
import javax.swing.plaf.*;
import org.pushingpixels.substance.api.skin.SubstanceOfficeSilver2007LookAndFeel;
class MyPopupMenuListener implements PopupMenuListener {
public void popupMenuCanceled(PopupMenuEvent popupMenuEvent) {
System.out.println("Canceled");
}
public void popupMenuWillBecomeInvisible(PopupMenuEvent popupMenuEvent) {
System.out.println("Becoming Invisible");
}
public void popupMenuWillBecomeVisible(PopupMenuEvent popupMenuEvent) {
System.out.println("Becoming Visible");
}
}
public class PopupMenuListenerDemo {
public static void main(final String args[]) {
final JFrame frame = new JFrame("PopupSample Example");
/*SwingUtilities.invokeLater(new Runnable() {
public void run() {
try {
UIManager.setLookAndFeel(new SubstanceOfficeSilver2007LookAndFeel());
SwingUtilities.updateComponentTreeUI(frame);
} catch (UnsupportedLookAndFeelException e) {
throw new RuntimeException(e);
}
}
});
try {
for (LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
System.out.println(info.getName());
if ("Nimbus".equals(info.getName())) {
UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (UnsupportedLookAndFeelException e) {
// handle exception
} catch (ClassNotFoundException e) {
// handle exception
} catch (InstantiationException e) {
// handle exception
} catch (IllegalAccessException e) {
// handle exception
}
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception e) {
e.printStackTrace();
}*/
UIResource res = new BorderUIResource.LineBorderUIResource(Color.red);
UIManager.put("PopupMenu.border", res);
JPopupMenu popupMenu = new JPopupMenu("Title");
//force to the Heavyweight Component or able for AWT Components
popupMenu.setLightWeightPopupEnabled(false);
PopupMenuListener popupMenuListener = new MyPopupMenuListener();
popupMenu.addPopupMenuListener(popupMenuListener);
JLabel lbl1 = new JLabel("My Title");
lbl1.setHorizontalAlignment(SwingConstants.CENTER);
popupMenu.add(lbl1);
JTextField text = new JTextField("My Title");
text.setHorizontalAlignment(SwingConstants.CENTER);
popupMenu.add(text);
String[] list = {"1", "2", "3", "4",};
JComboBox comb = new JComboBox(list);
popupMenu.add(comb);
JMenuItem pasteMenuItem = new JMenuItem("Paste");
pasteMenuItem.setEnabled(false);
popupMenu.add(pasteMenuItem);
popupMenu.addSeparator();
JMenuItem findMenuItem = new JMenuItem("Find");
popupMenu.add(findMenuItem);
JButton btn = new JButton();
JLabel lbl = new JLabel("My Title");
lbl.setHorizontalAlignment(SwingConstants.CENTER);
btn.setComponentPopupMenu(popupMenu);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(btn, BorderLayout.CENTER);
frame.add(lbl, BorderLayout.NORTH);
frame.setSize(350, 150);
SwingUtilities.invokeLater(new Runnable() {
public void run() {
frame.setVisible(true);
}
});
}
}
5 and terrible alignment for JLabel if there is added JComboBox :-) brrrrr !!!!

Wasn't even aware of that feature :-)
Digging a bit, it turns out that MotifLookAndFeel is the only of the core LAFs which support a title in the popup. It's realized by a custom border. Which you can do as well:
JPopupMenu popup = new JPopupMenu("My Label");
popup.add("dummy menu item");
Border titleUnderline = BorderFactory.createMatteBorder(1, 0, 0, 0, popup.getForeground());
TitledBorder labelBorder = BorderFactory.createTitledBorder(
titleUnderline, popup.getLabel(),
TitledBorder.CENTER, TitledBorder.ABOVE_TOP, popup.getFont(), popup.getForeground());
popup.setBorder(BorderFactory.createCompoundBorder(popup.getBorder(),
labelBorder));
JComponent comp = new JPanel();
comp.setComponentPopupMenu(popup);
Note: as far as I can see, there is no safe way to detect whether or not the LAF handles the title itself (which would result in doubling it)