Develop Reference

How to open new window by clicking label in java?

I want to open a new window when I click the label. By implementing a key pressed listener. But it is not working. Even nothing is happening.
JLabel lblNewLabel_2 = new JLabel("Create New Account!!!!");
lblNewLabel_2.setForeground(Color.GREEN);
lblNewLabel_2.addKeyListener(new KeyAdapter() {
#Override
public void keyPressed(KeyEvent e) {
Dosomething();
}
});
private void Dosomething() {
hide();
Account account=new Account();
account.visible();
}
protected static void hide() {
frame.hide();
}

You can use JButton as others say and remove its border to make it look like JLabel but if you really want to use JLabel and detect clicks I think you should write a MouseAdapter for it.
JLabel fooLabel = new JLabel("foo");
fooLabel.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
doSomething();
}
}
);
You can also override mouseClicked method but in that case the user must not move the cursor while clicking.

A JList rolls down when a JButton is clicked ? JAVA

I basically want to make a JList (whatToSearch) roll-down, or simply show its content, for selection, once a JButton (popDownButton) is clicked.
//SEARCH OPTIONS
popDownButton = new JButton(new ImageIcon(new ImageIcon("downArrow.png").getImage().getScaledInstance(20, 20, Image.SCALE_DEFAULT)));
whatToSearch = new JList(elementsToSearch);
whatToSearch.setVisibleRowCount(3);
whatToSearch.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
scroll = new JScrollPane(whatToSearch);
popDownButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
JOptionPane.showMessageDialog(null, scroll.getViewport());
}
});
add(popDownButton);
This bit of code works, but I'm looking for the content of the JList to be shown in the same interface, next to the button, rather than in another pop-up interface.

You can try this code, it's really easy:
popDownButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
JScrollBar vertical = scroll.getVerticalScrollBar();
vertical.setValue(vertical.getMaximum());
}
});
More ways: Scroll JScrollPane to bottom

Hope this helps:
popDownButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
whatToSearch.setSelectedIndex(elementsToSearch.getSize() - 1);
whatToSearch.ensureIndexIsVisible(elementsToSearch.getSize() - 1);
}
});

MouseExited event triggers when crossing an inner separator?

I have a JPopupMenu which contains an inner JMenu and a separator with addSeparator(). Due to some odd handling, I've added a MouseListener to the JPopupMenu which makes it invisible on a mouseExited event. This works fine, except that when the mouse tries to cross over the separator, it's triggering the event (even though the JPopupMenu is the super component).
If I remove the addSeparator() line, it works as expected.
Is there any way to work around this? Or have I not set up the listener properly?
The code is like the following:
JPopupMenu popupMenu = new JPopupMenu();
JMenu innerMenu = new JMenu("Inner");
// ... add JMenuItems
popupMenu.add(innerMenu);
popupMenu.addSeparator();
popupMenu.add(new JMenuItem("Exit"));
popupMenu.addMouseListener(new MouseAdapter() {
#Override
public void mouseExited(MouseEvent e) {
popupMenu.setVisible(false);
}
});
Full Compilable Example
Simply comment and uncomment the popupMenu.addSeparator() line to notice the different behaviors
public class Test {
public static void main(String[] args) throws Exception {
if(!SystemTray.isSupported()) {
throw new UnsupportedOperationException("SystemTray is not supported.");
}
final TrayIcon trayIcon = new TrayIcon(ImageIO.read(new File("resources/icon.gif")));
final JPopupMenu popupMenu = new JPopupMenu();
JMenu intervalMenu = new JMenu("Interval");
ButtonGroup itemGroup = new ButtonGroup();
JRadioButtonMenuItem oneSecondMenuItem = new JRadioButtonMenuItem("1 sec");
itemGroup.add(oneSecondMenuItem);
JRadioButtonMenuItem twoSecondMenuItem = new JRadioButtonMenuItem("2 sec");
itemGroup.add(twoSecondMenuItem);
intervalMenu.add(oneSecondMenuItem);
intervalMenu.add(twoSecondMenuItem);
popupMenu.add(intervalMenu);
popupMenu.addSeparator();
JMenuItem exitMenuItem = new JMenuItem("Exit");
exitMenuItem.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
SystemTray.getSystemTray().remove(trayIcon);
System.exit(0);
}
});
popupMenu.add(exitMenuItem);
//Thanks to Artem Ananiev for this implementation idea
//https://weblogs.java.net/blog/ixmal/archive/2006/05/using_jpopupmen.html
trayIcon.addMouseListener(new MouseAdapter() {
#Override
public void mouseReleased(MouseEvent e) {
if(e.getButton() == MouseEvent.BUTTON3) {
popupMenu.setLocation(e.getX() - 40, e.getY() - 40);
popupMenu.setInvoker(popupMenu);
popupMenu.setVisible(true);
}
}
});
popupMenu.addMouseListener(new MouseAdapter() {
#Override
public void mouseExited(MouseEvent e) {
popupMenu.setVisible(false);
}
});
SystemTray.getSystemTray().add(trayIcon);
}
}

Wow, you are using a sytem tray icon. That information might have been important to know. That is why a SSCCE should be posted with EVERY question.
Anyway the following seems to work:
if (! popupMenu.contains( e.getPoint() ) )
popupMenu.setVisible(false);
Edit:
It looks like the problem is that the JSeparator does not listen for MouseEvents by default so all the mouse events are passed to its parent. So when you leave a JMenuItem, the mouseEntered() event is generated for the popup menu and then when you re-enter another JMenuItem the mouseExited() event is generated.
If you enable MouseEvents for the JSeparator then it look like the JPopupMenu doesn't get the event
//popupMenu.addSeparator();
popupMenu.add( new MySeparator() );
...
static class MySeparator extends JSeparator
{
public MySeparator( )
{
super( JSeparator.HORIZONTAL );
enableEvents(AWTEvent.MOUSE_EVENT_MASK);
}
/**
* Returns the name of the L&F class that renders this component.
*
* #return the string "PopupMenuSeparatorUI"
* #see JComponent#getUIClassID
* #see UIDefaults#getUI
*/
public String getUIClassID()
{
return "PopupMenuSeparatorUI";
}
}

activate and deactivate ComboBox

How can I make the comboBox available when the checkBox was uncheck (vice versa)
Why the comboBox is still disable after I unChecked the checkBox?
choice [] = {"A","B","C"};
JComboBox a = new JComboBox(choice);
JCheckBox chk = new JCheckBox("choice");
...
a.addActionListener(this);
chk.addActionListener(this);
...
public void actionPerformed(ActionEvent e) {
//disable the a comboBox when the checkBox chk was checked
if(e.getSource()==chk)
a.setEnabled(false);
//enable the a comboBox when the checkBox chk was unchecked
else if(e.getSource()!=chk)
a.setEnabled(true);
}

If I understand you correctly I think all that you need to do is to change the enabled state of the combo box based on the current value of the checkbox:
public void actionPerformed(ActionEvent e) {
if (e.getSource()==chk) {
a.setEnabled(chk.isSelected());
}
}

I have a similar set up, and I use an Item Listener, like so:
CheckBox.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if(e.getStateChange()==ItemEvent.SELECTED){
ComboBox.setEnabled(true);
}else if(e.getStateChange()==ItemEvent.DESELECTED){
ComboBox.setSelectedIndex(-1);
ComboBox.setEnabled(false);
}
}
});
This way the behaviour is different when selected and deselected.

I treid this and worked..
public class JF extends JFrame implements ActionListener {
String choice [] = {"A","B","C"};
JComboBox a = new JComboBox(choice);
JCheckBox chk = new JCheckBox("choice");
JF()
{
this.add(a, BorderLayout.NORTH);
this.add(chk, BorderLayout.CENTER);
setDefaultCloseOperation(EXIT_ON_CLOSE);
a.addActionListener(this);
chk.addActionListener(this);
}
public void actionPerformed(ActionEvent e) {
//NOTE THE FOLLOWING LINE!!!!
if(e.getSource()==chk)
a.setEnabled(chk.isSelected());
}
public static void main(String[] args) {
new JF().setVisible(true);
}
}
Your old code didn't work because, even unchecking a checkbox triggers the event. The source of the trigger is the checkbox.. so both while checking and unchecking the event source was chk

if (e.getSource() == chckbxModificar) {
if (chckbxModificar.isSelected()) {
cbxImpuesto.setEnabled(true);
cbxMoneda.setEnabled(true);
txtPorcentaje.setEditable(true);
txtSimbolo.setEditable(true);
} else {
cbxImpuesto.setEnabled(false);
cbxMoneda.setEnabled(false);
txtPorcentaje.setEditable(false);
txtSimbolo.setEditable(false);
}
}

Showing/hiding a JPopupMenu from a JButton; FocusListener not working?

I needed a JButton with an attached dropdown style menu. So I took a JPopupMenu and attached it to the JButton in the way you can see in the code below. What it needs to do is this:
show the popup when clicked
hide it if clicked a second time
hide it if an item is selected in the popup
hide it if the user clicks somewhere else in the screen
These 4 things work, but because of the boolean flag I'm using, if the user clicks somewhere else or selects an item, I have to click twice on the button before it shows up again. That's why I tried to add a FocusListener (which is absolutely not responding) to fix that and set the flag false in these cases.
EDIT: Last attempt in an answer post...
Here are the listeners: (It's in a class extending JButton, so the second listener is on the JButton.)
// Show popup on left click.
menu.addFocusListener(new FocusListener() {
#Override
public void focusLost(FocusEvent e) {
System.out.println("LOST FOCUS");
isShowingPopup = false;
}
#Override
public void focusGained(FocusEvent e) {
System.out.println("GAINED FOCUS");
}
});
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("isShowingPopup: " + isShowingPopup);
if (isShowingPopup) {
isShowingPopup = false;
} else {
Component c = (Component) e.getSource();
menu.show(c, -1, c.getHeight());
isShowingPopup = true;
}
}
});
I've been fighting with this for way too long now. If someone can give me a clue about what's wrong with this, it would be great!
Thanks!
Code:
public class Button extends JButton {
// Icon.
private static final ImageIcon ARROW_SOUTH = new ImageIcon("ArrowSouth.png");
// Unit popup menu.
private final JPopupMenu menu;
// Is the popup showing or not?
private boolean isShowingPopup = false;
public Button(int height) {
super(ARROW_SOUTH);
menu = new JPopupMenu(); // menu is populated somewhere else
// FocusListener on the JPopupMenu
menu.addFocusListener(new FocusListener() {
#Override
public void focusLost(FocusEvent e) {
System.out.println("LOST FOCUS");
isShowingPopup = false;
}
#Override
public void focusGained(FocusEvent e) {
System.out.println("GAINED FOCUS");
}
});
// ComponentListener on the JPopupMenu
menu.addComponentListener(new ComponentListener() {
#Override
public void componentShown(ComponentEvent e) {
System.out.println("SHOWN");
}
#Override
public void componentResized(ComponentEvent e) {
System.out.println("RESIZED");
}
#Override
public void componentMoved(ComponentEvent e) {
System.out.println("MOVED");
}
#Override
public void componentHidden(ComponentEvent e) {
System.out.println("HIDDEN");
}
});
// ActionListener on the JButton
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("isShowingPopup: " + isShowingPopup);
if (isShowingPopup) {
menu.requestFocus();
isShowingPopup = false;
} else {
Component c = (Component) e.getSource();
menu.show(c, -1, c.getHeight());
isShowingPopup = true;
}
}
});
// Skip when navigating with TAB.
setFocusable(true); // Was false first and should be false in the end.
menu.setFocusable(true);
}
}

Here's a variant of Amber Shah's "big hack" suggestion I just made. Without the isShowingPopup flag...
It's not bulletproof, but it works quite well until someone comes in with an incredibly slow click to close the popup (or a very fast second click to reopen it...).
public class Button extends JButton {
// Icon.
private static final ImageIcon ARROW_SOUTH = new ImageIcon("ArrowSouth.png");
// Popup menu.
private final JPopupMenu menu;
// Last time the popup closed.
private long timeLastShown = 0;
public Button(int height) {
super(ARROW_SOUTH);
menu = new JPopupMenu(); // Populated somewhere else.
// Show and hide popup on left click.
menu.addPopupMenuListener(new PopupMenuListener() {
#Override
public void popupMenuWillBecomeInvisible(PopupMenuEvent arg0) {
timeLastShown = System.currentTimeMillis();
}
#Override public void popupMenuWillBecomeVisible(PopupMenuEvent arg0) {}
#Override public void popupMenuCanceled(PopupMenuEvent arg0) {}
});
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if ((System.currentTimeMillis() - timeLastShown) > 300) {
Component c = (Component) e.getSource();
menu.show(c, -1, c.getHeight());
}
}
});
// Skip when navigating with TAB.
setFocusable(false);
}
}
As I said in comments, that's not the most elegant solution, but it's horribly simple and it works in 98% of the cases.
Open to suggestions!

Here is another approach which is not too bad of a hack, if not elegant, and which, as far as I could tell, works. First, at the very top, I added a second boolean called showPopup.
The FocusListener has to be as follows:
menu.addFocusListener(new FocusListener() {
#Override
public void focusLost(FocusEvent e) {
System.out.println("LOST FOCUS");
isShowingPopup = false;
}
#Override
public void focusGained(FocusEvent e) {
System.out.println("GAINED FOCUS");
isShowingPopup = true;
}
});
The isShowingPopup boolean does not get changed anywhere else--if it gains focus, it assumes it's shown and if it loses focus, it assumes it isn't.
Next, the ActionListener on the button is different:
addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("isShowingPopup: " + isShowingPopup);
if (showPopup) {
Component c = (Component) e.getSource();
menu.show(c, -1, c.getHeight());
menu.requestFocus();
} else {
showPopup = true;
}
}
});
Now comes the really new bit. It's a MouseListener on the button:
addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
System.out.println("ispopup?: " + isShowingPopup);
if (isShowingPopup) {
showPopup = false;
}
}
#Override
public void mouseReleased(MouseEvent e) {
showPopup = true;
}
});
Basically, mousePressed gets called before the menu loses focus, so isShowingPopup reflects whether the popup was shown before the button is pressed. Then, if the menu was there, we just set showPopup to false, so that the actionPerformed method does not show the menu once it gets called (after the mouse is let go).
This behaved as expected in every case but one: if the menu was showing and the user pressed the mouse on the button but released it outside of it, actionPerformed was never called. This meant that showPopup remained false and the menu was not shown the next time the button was pressed. To fix this, the mouseReleased method resets showPopup. The mouseReleased method gets called after actionPerformed, as far as I can tell.
I played around with the resulting button for a bit, doing all the things I could think of to the button, and it worked as expected. However, I am not 100% sure that the events will always happen in the same order.
Ultimately, I think this is, at least, worth trying.

You could use the JPopupMenu.isVisible() instead of your Boolean variable to check the current state of the popup menu.

Have you tried adding a ComponentListener to the JPopupMenu, so that you know when it's been shown and hidden (and update your isShowingPopup flag accordingly)? I'm not sure listening for focus changes is necessarily the right approach.

What you need is a PopupMenuListener:
menu.addPopupMenuListener(new PopupMenuListener() {
#Override
public void popupMenuWillBecomeVisible(PopupMenuEvent arg0) {
}
#Override
public void popupMenuWillBecomeInvisible(PopupMenuEvent arg0) {
System.out.println("MENU INVIS");
isShowingPopup = false;
}
#Override
public void popupMenuCanceled(PopupMenuEvent arg0) {
System.out.println("MENU CANCELLED");
isShowingPopup = false;
}
});
I inserted this into your code and verified that it works.

Well, I can't be sure without seeing all of your code, but is it possible that the popup never actually gets focus at all? I've had problems with things' not getting focus properly in Swing before, so it could be the culprit. Try calling setFocusable(true) on the menu and then calling requestFocus() when you make the menu appear.

I tried the Answer of Tikhon Jelvis (introducing a smart combination of focusListener and mouseListener). It does not work for me on Linux (Java7/gtk). :-(
Reading http://docs.oracle.com/javase/7/docs/api/javax/swing/JComponent.html#requestFocus%28%29 there is written "Note that the use of this method is discouraged because its behavior is platform dependent."
It may be that the order of listener calls changed with Java7 or it changes with GTK vs Windows. I would not recommend this solution if you want to be platform independent.
BTW: I created a new account on stackoverflow to give this hint. It seems I am not allowed to comment to his answer (because of reputation). But it seems I have a button to edit it. This stackoverflow is a very funny thing. :-)