Develop Reference

Higlight text in JTextField but only when tabbing

I want to create a JDialog where the text in the textfields is selected but only if the focus is gained from keyboard (TAB, CTRL+TAB). I have found several topics on this matter but had problems with implementing it.
Here is one which I was trying.
And my code:
public class Dialogg extends JDialog implements FocusListener, MouseListener {
private boolean focusFromMouse = false;
public Dialogg() {
JTextField tf1 = new JTextField("text1");
JTextField tf2 = new JTextField("text2");
tf1.addMouseListener(this);
tf2.addMouseListener(this);
tf1.addFocusListener(this);
tf2.addFocusListener(this);
}
#Override
public void focusGained(FocusEvent e) {
if (!focusFromMouse) {
JTextField tf = (JTextField) e.getComponent();
tf.selectAll();
focusFromMouse = true;
}
}
#Override
public void focusLost(FocusEvent e) {
focusFromMouse = false;
}
#Override
public void mouseClicked(MouseEvent e) {
focusFromMouse = true;
}
}
It does not work as intended, it does not matter what is focus source the text always highlights. When I run the code and follow it step by step it turns out that focusGained code happens before mouseClicked code so the flag is not reset when it should. Any hints?
EDIT:
As suggested by M. Prokhorov I have deleted less relevant (for the question) lines from the code.Thank you.
EDIT 2:
I am trying to wrap focus listener as suggested by camickr. It looks like this now:
tf1.addFocusListener(new FocusAdapter() {
public void focusGained(FocusEvent evt){
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
if (!focusFromMouse){
tf1.selectAll();
focusFromMouse=true;
}
}
});
}
public void focusLost(FocusEvent evt){
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
focusFromMouse=false;
}
});
}
});
public void mouseClicked(MouseEvent e) {
focusFromMouse=true;
I am printing line after each event to see the action order and still mouseClicked happens last. What am I doing wrong?
EDIT 3:
OK, I have found a solution which fulfils requirements of my simple Dialog.
I could not find a way of doing this with use of invokeLater or EventQueue. Vladislav's method works but as I understand it restricts the user to only use the keyboard.
I have used the initial approach but I have added an auxiliary variable and few conditions which allow to pass the flag "unharmed" trough Events that should not change the flag at given moment. It may not be subtle or universal but works for my app. Here is the code:
public void focusGained(FocusEvent e) {
if(!focusFromMouse){
if (higlight){
JTextField tf = (JTextField) e.getComponent();
tf.selectAll();
focusFromMouse=false;
}
}
}
public void focusLost(FocusEvent e) {
if (focusFromMouse){
higlight=false;
focusFromMouse=false;
}else{
higlight=true;
}
}
public void mousePressed(MouseEvent e) {
focusFromMouse=true;
}

At the first, by default, focus on JTextField is requested by mouse-press event, not by mouse-click.
So, this method:
public void mouseClicked(MouseEvent e) {
focusFromMouse = true;
}
is useless because the mouse-click event is triggered after the mouse-press event.
One way to solve your problem is to remove all native MouseListeners from JTextField:
...
for( MouseListener ml : tf1.getMouseListeners() ){
tf1.removeMouseListener(ml);
}
for( MouseMotionListener mml : tf1.getMouseMotionListeners() ){
tf1.removeMouseMotionListener(mml);
}
...
Another way is to handle all mouse events and consume those of them, which are triggered by JTextField:
Toolkit.getDefaultToolkit().addAWTEventListener(new AWTEventListener() {
#Override
public void eventDispatched(AWTEvent event) {
if( event.getSource() == tf1 ){
((MouseEvent)event).consume();
}
}
}, AWTEvent.MOUSE_EVENT_MASK);

When I run the code and follow it step by step it turns out that focusGained code happens before mouseClicked
Wrap the code in the FocusListener in a SwingUtilities.invokeLater(). The will place the code on the end of the Event Dispatch Thread (EDT), so the code will run after the variable in the MouseListener has been set.
See Concurrency in Swing for more information about the EDT.
Edit:
Just noticed the other answer. You might be able to do something simpler. Istead of listener for mouseClicked, listen for mousePressed. A mouseClicked event is only generated AFTER the mouseReleased event, so by that time the FocusListener logic has already been executed, even when added to the end of the EDT.
Edit 2:
If the above doesn't work then you might be able to use the EventQueue.peek() method to see if a MouseEvent is on the queue. This might even be easier than worrying about using the invokeLater.

JTable clicked row listener

I have a dynamic JTable that contains a string matrix, and I need to write a listener that when double click on a row, read a specific column and make some computation on it. Which kind of listener should I use?

Implement the MouseListener or extend the MouseAdapter. You can try something like this:
yourJTable.addMouseListener(new MouseAdapter(){
public void mouseClicked(MouseEvent evnt) {
if (evnt.getClickCount() == 1) {
getPropertyFromRow((String)(t_property.getValueAt(yourJTable.getSelectedRow(),0)));
}
}
});

Try using the getClickCount() of MouseEvent method after implementing the MouseListener or extending the MouseAdapter . Sample :
yourJTable.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (e.getClickCount() == 2) { // check if a double click
// your code here
}
}
});

mouse pressed->drag->released. in java

Excuse me:
I just can't know how to link these successive operation?
Mouse pressed and then drag then release. If an user doesn't do this operation some action won't happen...
Should I add code as the is already pressed to distinguish that?
The constant MOUSE_MOVED doesn't work since Eclipse told me it doesn't know it although I find the parameter in mouse event api
I don't know what's going on... Please help!

Implement a MouseInputListener using a MouseInputAdapter subclass and handle the mousePressed, mouseDragged, and the mouseReleased events.
Take a look at this tutorial for examples.

Here is a simple class that encapsulates the drag detection:
public abstract static class MouseDragListener {
java.awt.Component component;
MouseEvent dragStart;
public MouseDragListener(java.awt.Component component) {
super();
this.component = component;
component.addMouseMotionListener(new MouseAdapter() {
public void mouseMoved(MouseEvent e) {
dragStart = null;
}
public void mouseDragged(MouseEvent e) {
if (dragStart == null)
dragStart = e;
}
});
component.addMouseListener(new MouseAdapter() {
public void mouseReleased(MouseEvent e) {
if (dragStart != null) {
dragReleased(dragStart, e);
}
}
});
}
then to use:
new MouseDragListener(center){
void dragReleased(MouseEvent start,MouseEvent end){
// do something ...
}
}

Right click on JButton

I am trying to write a Minesweeper clone in Java for fun. I have a grid of JButtons whose labels I will change to represent the danger count, flags, etc.
My problem is, I don't know how to get a right click on a JButton to depress the button. I've done the following:
button.addMouseListener(new MouseAdapter(){
public void mouseClicked(MouseEvent e){
boolean mine = field.isMine(x, y);
if (e.isPopupTrigger()) {
button.setText("F");
}
else {
if (mine) {
button.setText("X");
}
}
}
});
This doesn't seem to be working at all; the "F" is never shown, only the "X" part. But more importantly, this does nothing for depressing the button.
EDIT: Macs have popup trigger happen on mousePress, not mouseClick.
EDIT: Here's the solution I worked out based off of accepted answer:
button.addMouseListener(new MouseAdapter(){
boolean pressed;
#Override
public void mousePressed(MouseEvent e) {
button.getModel().setArmed(true);
button.getModel().setPressed(true);
pressed = true;
}
#Override
public void mouseReleased(MouseEvent e) {
//if(isRightButtonPressed) {underlyingButton.getModel().setPressed(true));
button.getModel().setArmed(false);
button.getModel().setPressed(false);
if (pressed) {
if (SwingUtilities.isRightMouseButton(e)) {
button.setText("F");
}
else {
button.setText("X");
}
}
pressed = false;
}
#Override
public void mouseExited(MouseEvent e) {
pressed = false;
}
#Override
public void mouseEntered(MouseEvent e) {
pressed = true;
}
});
add(button);
Minesweeper clone http://grab.by/1y9z

Button can't be pressed by right click. Add such a lines to you mouse listener
mousePressed:
if(isRightButtonPressed) {underlyingButton.getModel().setPressed(true));
mouseReleased:
if(needReset) {underlyingButton.getModel().setPressed(false));
or do there whatever want.

I wouldn't use isPopupTrigger but directly check for the right button:
button.addMouseListener(new MouseAdapter(){
public void mouseClicked(MouseEvent e){
boolean mine = field.isMine(x, y);
if (e.getButton() == MouseEvent.BUTTON2) {
button.setText("F");
}
...

Just a small addition: the simplest way to check for the right button is SwingUtilities.isRightMouseButton

As you have mentioned that checking for "mousePressed" solved your issue. And the Javadoc of isPopupTrigger would explain the need for this:
public boolean isPopupTrigger()
...
Note: Popup menus are triggered differently on different systems. Therefore, isPopupTrigger should be checked in both mousePressed and mouseReleased for proper cross-platform functionality.
Also see the section on The Mouse Listener API in the Java Swing tutorial.

MouseEvent has some properties
static int BUTTON1
static int BUTTON2
static int BUTTON3
among others. Check those when your event fires.
EDIT
public int getButton()
Returns which, if any, of the mouse buttons has changed state.

The button being visibly depressed on right click isn't part of the "normal" behavior of buttons. You may be able to fake it using JToggleButtons, or simply changing the button's background color and maybe border while the right mouse button is being held down.

If you are certain that the event is properly being triggered (debug FTW!) and that the button.setText("F") is happening, then perhaps you simply need to repaint.
Repaint the button.
http://java.sun.com/javase/6/docs/api/javax/swing/JComponent.html#repaint(java.awt.Rectangle)

This works for me fine on Mac:
import java.awt.event.*;
import javax.swing.*;
public class ButtonTest extends JFrame {
JButton button;
public ButtonTest() {
button = new JButton("W");
button.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (e.getButton() == 3) { // if right click
button.setText("F");
button.getModel().setPressed(false);
// button.setEnabled(true);
} else {
button.setText("X");
button.getModel().setPressed(true);
// button.setEnabled(false);
}
}
});
this.add(button);
this.setVisible(true);
}
public static void main(String[] args) {
new ButtonTest();
}
}
You might as well check for e.getButton() == 2 but I don't know when this one is triggered on Macs.

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. :-)