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How do I update JLabel from antoher class?

I need to use a thread to change the position of my JLabel (movingDisplay) every second when I click on my button (btnDisplay) and for the thread to stop when I click on my other button (btnDStop). I have a class called MoveDisplay that implements Runnable and does this action when I click on btnDisplay. After MoveDisplay has randomized x and y for my JLabel, it's supposed to send x and y back to my main class where it updates the position of the JLabel. I have a method in my mainclass to update the JLabel position however I get a NullPointerException when trying to do so. In fact it doesn't work changing any component at all from MoveDisplay class.
public class Main {
public static void main(String[] args) {
GUIFrame test = new GUIFrame();
}
}
MoveDisplay class:
public class MoveDisplay implements Runnable {
private GUIFrame gui;
private boolean moving = true;
private Thread thread;
public void run() {
gui = new GUIFrame();
if (moving) {
Random rand = new Random();
while (moving) {
int x = rand.nextInt(150) + 1;
int y = rand.nextInt(150) + 1;
gui.moveDisplay(x, y, 100, 100);
try {
thread.sleep(1000);
} catch (InterruptedException e) {
break;
}
}
}
}
public void start() {
thread = new Thread(new MoveDisplay());
thread.start();
}
public void stop() {
thread.interrupt();
System.out.println("Stopped");
}
}
GUIFrame class:
public class GUIFrame {
private JFrame frame; // The Main window
private JLabel movingDisplay;
private boolean playing = true;
private boolean moving = true;
private MoveDisplay moveDisplay = new MoveDisplay();
/**
* Starts the application
*/
public void Start() {
frame = new JFrame();
frame.setBounds(0, 0, 494, 437);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(null);
frame.setTitle("Multiple Thread Demonstrator");
InitializeGUI(); // Fill in components
frame.setVisible(true);
frame.setResizable(false); // Prevent user from change size
frame.setLocationRelativeTo(null); // Start middle screen
}
public void InitializeGUI() {
// The moving display outer panel
JPanel pnlDisplay = new JPanel();
Border b2 = BorderFactory.createTitledBorder("Display Thread");
pnlDisplay.setBorder(b2);
pnlDisplay.setBounds(12, 118, 222, 269);
pnlDisplay.setLayout(null);
// Add buttons and drawing panel to this panel
btnDisplay = new JButton("Start Display");
btnDisplay.setBounds(10, 226, 121, 23);
pnlDisplay.add(btnDisplay);
btnDStop = new JButton("Stop");
btnDStop.setBounds(135, 226, 75, 23);
pnlDisplay.add(btnDStop);
pnlMove = new JPanel();
pnlMove.setBounds(10, 19, 200, 200);
Border b21 = BorderFactory.createLineBorder(Color.black);
pnlMove.setBorder(b21);
pnlDisplay.add(pnlMove);
// Then add this to main window
frame.add(pnlDisplay);
movingDisplay = new JLabel("DisplayThread");
pnlMove.add(movingDisplay);
btnDStop.setEnabled(false);
btnDisplay.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
moving = true;
btnDisplay.setEnabled(false);
btnDStop.setEnabled(true);
startMoveDisplay();
}
});
btnDStop.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
moving = false;
btnDisplay.setEnabled(true);
btnDStop.setEnabled(false);
startMoveDisplay();
}
});
}
public void startMoveDisplay() {
if(moving) {
moveDisplay.start();
}
else {
moveDisplay.stop();
}
}
public void moveDisplay(int x, int y, int a, int b) {
movingDisplay.setBounds(10,10,150,150);
}
}

I've checked the code and in the MoveDisplay.run() you were creating a new frame, but in it's constructor the panel wasn't initialized, which triggered the NPE. Because of this I've refactored the GUIFrame constructor to initialeze all components (invoked the Start() method) and removed the new frame's initialization from the run method. Here are the modified classed
public class MoveDisplay {
private GUIFrame gui;
private volatile boolean moving;
public MoveDisplay(GUIFrame gui) {
this.gui = gui;
}
public void start() {
moving = true;
Random rand = new Random();
while (moving) {
int x = rand.nextInt(150) + 1;
int y = rand.nextInt(150) + 1;
gui.moveDisplay(x, y, 100, 100);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
public void stop() {
moving = false;
}
}
And here is the new frame class
public class GUIFrame {
private JFrame frame; // The Main window
private JLabel movingDisplay;
private boolean playing = true;
private boolean moving = true;
private MoveDisplay moveDisplay;
public GUIFrame() {
Start();
}
/**
* Starts the application
*/
private void Start() {
frame = new JFrame();
frame.setBounds(0, 0, 494, 437);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(null);
frame.setTitle("Multiple Thread Demonstrator");
InitializeGUI(); // Fill in components
frame.setVisible(true);
frame.setResizable(false); // Prevent user from change size
frame.setLocationRelativeTo(null); // Start middle screen
moveDisplay = new MoveDisplay(this);
}
public void InitializeGUI() {
// The moving display outer panel
JPanel pnlDisplay = new JPanel();
Border b2 = BorderFactory.createTitledBorder("Display Thread");
pnlDisplay.setBorder(b2);
pnlDisplay.setBounds(12, 118, 222, 269);
pnlDisplay.setLayout(null);
// Add buttons and drawing panel to this panel
JButton btnDisplay = new JButton("Start Display");
btnDisplay.setBounds(10, 226, 121, 23);
pnlDisplay.add(btnDisplay);
JButton btnDStop = new JButton("Stop");
btnDStop.setBounds(135, 226, 75, 23);
pnlDisplay.add(btnDStop);
JPanel pnlMove = new JPanel();
pnlMove.setBounds(10, 19, 200, 200);
Border b21 = BorderFactory.createLineBorder(Color.black);
pnlMove.setBorder(b21);
pnlDisplay.add(pnlMove);
// Then add this to main window
frame.add(pnlDisplay);
movingDisplay = new JLabel("DisplayThread");
pnlMove.add(movingDisplay);
btnDStop.setEnabled(false);
btnDisplay.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
moving = true;
btnDisplay.setEnabled(false);
btnDStop.setEnabled(true);
startMoveDisplay();
}
});
btnDStop.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
moving = false;
btnDisplay.setEnabled(true);
btnDStop.setEnabled(false);
startMoveDisplay();
}
});
}
public void startMoveDisplay() {
if(moving) {
new Thread(new Runnable() {
#Override
public void run() {
moveDisplay.start();
}
}).start();
} else {
moveDisplay.stop();
}
}
public void moveDisplay(int x, int y, int a, int b) {
movingDisplay.setBounds(x, y, a, b);
}
}

You have to get a reference to the existing GUIFrame instance instead of creating a new one, try this:
MoveDisplay
public class MoveDisplay implements Runnable {
private GUIFrame gui;
Random rand = new Random();
volatile boolean moving;
public MoveDispaly(GUIFrame gui){
this.gui = gui;
}
public void run() {
while (moving) {
int x = rand.nextInt(150) + 1;
int y = rand.nextInt(150) + 1;
try {
SwingUtilities.invokeAndWait(new Runnable(){
public void run(){
gui.moveDisplay(x, y, 100, 100);
}
});
thread.sleep(1000);
} catch (InterruptedException e) {
break;
}
}
}
public void start() {
moving = true;
thread = new Thread(new MoveDisplay());
thread.start();
}
public void stop() {
moving = false;
}
}
GUIFrame
public class GUIFrame{
MoveDisplay moveDisplay = new MoveDisplay(this);
...
}
Also, you have to run the part of the code that changes the GUI on the EDT thread.
Is not a good idea to stop a thread by interrupting it, you can stop it by setting the moving variable to false.

Maybe you can also use the Singleton Pattern to get the original instance of GUIFrame:
public static class instanceClassA {
private static instanceClassA = null;
public static instanceClassA(){
if(instance == null){
instance = instanceClassA();
}
return instance;
}
}

Mouse event goes through the component

I have added a simple program to illustrate.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class SimpleInternalFrame extends Frame
{
private static final long serialVersionUID = 1L;
static JLayeredPane desktop;
JInternalFrame internalFrame;
public SimpleInternalFrame()
{
super("Internal Frame Demo");
setSize(500, 400);
Panel p = new Panel();
add(p, BorderLayout.SOUTH);
addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
desktop = new JDesktopPane();
desktop.setOpaque(true);
add(desktop, BorderLayout.CENTER);
}
public static void main(String args[])
{
SimpleInternalFrame sif = new SimpleInternalFrame();
sif.setVisible(true);
final JInternalFrame internalFrame = new JInternalFrame("Internal Frame 1", true, true, true, true);
internalFrame.setBounds(50, 50, 300, 200);
desktop.add(internalFrame, new Integer(1));
JTextField tf = new JTextField();
tf.addMouseListener(new MouseAdapter()
{
public void mouseClicked(MouseEvent evt)
{
System.out.println("Text Field " + evt.getClickCount());
}
});
internalFrame.add(tf);
internalFrame.setVisible(true);
final JInternalFrame internalFrame2 = new JInternalFrame("Internal Frame 1", true, true, true, true);
internalFrame2.setBounds(50, 50, 200, 100);
desktop.add(internalFrame2, new Integer(1));
JButton jb = new JButton("click me");
jb.addMouseListener(new MouseAdapter()
{
public void mouseClicked(MouseEvent evt)
{
if (evt.getClickCount() == 1)
{
System.out.println("Button " + evt.getClickCount());
internalFrame2.setVisible(false);
}
}
});
internalFrame2.add(jb);
internalFrame2.setVisible(true);
}
}
When running the code it will open a two internal frames.One has button.One has text field.Button will close the first Internal frame for single click.
Double click the button.It will show click count 2 as in text field.
This is the problem we have currently in the project.Thing is second frame dose not has text field in actual project.It has click-able item that work in double click event.
This is the problem we have currently.Please help.

tf.addMouseListener(new MouseAdapter() {
int cc;
public void mouseClicked(MouseEvent evt) {
int ccount = evt.getClickCount();
if(ccount == 1 || ccount == cc+1) {
cc = ccount;
System.out.println("Text Field " + evt.getClickCount());
}
}
});
This will work more than once.
Another possibility is to use components with overriden processMouseEvent():
public class SimpleInternalFrame extends Frame {
...
private MouseEvent lastMouseEvent;
public boolean checkEvent(MouseEvent e) {
if(lastMouseEvent != null) {
if(lastMouseEvent.getSource() != e.getSource()) {
if(e.getClickCount() != 1) {
return false;
}
}
}
lastMouseEvent = e;
return true;
}
class MTextField extends JTextField {
protected void processMouseEvent(MouseEvent e) {
if (checkEvent(e)) {
super.processMouseEvent(e);
}
}
}
class MButton extends JButton {
protected void processMouseEvent(MouseEvent e) {
if (checkEvent(e)) {
super.processMouseEvent(e);
}
}
}
public JTextField createText() {
return new MTextField();
}
public MButton createButton() {
return new MButton();
}
} //end of SimpleInternalFrame
create components:
final JTextField tf = sif.createText();
tf.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent evt) {
System.out.println("Text Field " + evt.getClickCount());
}
});
JButton jb = sif.createButton();
jb.setText("click me");
jb.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent evt) {
if (evt.getClickCount() == 1) {
internalFrame2.setVisible(false);
}
}
});

You can use a static boolean called myTurn initialized to false and then in the textfield mouseClicked:
tf.addMouseListener(new MouseAdapter()
{
public void mouseClicked(MouseEvent evt)
{
if (evt.getClickCount() >= 2 && !myTurn) {
myTurn = true;
evt.consume();
} else {
myTurn = true; //Initial one click on me
System.out.println("Text Field " + evt.getClickCount());
evt.consume();
}
}
});
This solves your problem in this basic case, but I don't know if it will in your application. The problem is that if you click the TextField before the Button, you can experience the same problem. However, if that isn't possible, this will solve it.

While searching on internet and reading some documents i was able get a solution.
int timerinterval = (int) Toolkit.getDefaultToolkit().
getDesktopProperty("awt.multiClickInterval");
final Timer timer = new Timer(timerinterval, new ActionListener()
{
public void actionPerformed(ActionEvent acEvt)
{
internalFrame2.setVisible(false);
}
});
jb.addMouseListener(new MouseAdapter()
{
public void mouseClicked(final MouseEvent evt)
{
System.out.println("Button " + evt.getClickCount());
timer.setRepeats(false);
timer.start();
if (evt.getClickCount() > 1)
{
timer.restart();
}
}
});
One draw back of this solution is if user do a single click he need to wait
timerinterval unnecessarily.Any one has better solution please post.

Generate a double click mouse event in Java Swing

I am trying to generate a double click mouse event on the EDT as follows:
SwingUtilities.invokeLater(new Runnable() {
public void run() {
component.dispatchEvent(new MouseEvent(
component,
MouseEvent.MOUSE_CLICKED,
System.currentTimeMillis(),
InputEvent.BUTTON1_MASK,
x, y,
2, // click count
false
));
}
});
This does not seem to dispatch a double click event, even though I am setting the click count to 2.
Any suggestions or examples?

Considering:
final JButton clickTwiceButton = new JButton();
final JButton fireEventButton = new JButton();
Listeners:
clickTwiceButton.addMouseListener(new java.awt.event.MouseAdapter() {
public void mouseClicked(java.awt.event.MouseEvent evt) {
if (evt.getClickCount() == 2) {
JOptionPane.showMessageDialog(null, "Double clicked!");
}
}
});
fireEventButton.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
// Invoking later for no reason, just to simulate your code
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
clickTwiceButton.dispatchEvent(new MouseEvent(
fireEventButton,
MouseEvent.MOUSE_CLICKED,
1,
MouseEvent.BUTTON1,
0, 0,
2,
false
));
}
});
}
});
When I click fireEventButton the MouseEvent gets correctly dispatched to clickTwiceButton, and the dialog appears as expected.
So, as #Andrew pointed out, the problem seems to be that either you are firing the event to the wrong component or that something is not right with the registered MouseListener / MouseAdapter code.
Use component.getMouseListeners() to check for your component Listeners and debug the code that handles its events.

The method is very simple. You should get the time of the first click and the time of the second click, then you can do a condition in between.
Method code as below:
private boolean state=false;
private long first_pressed;
JButton btnAdd = new JButton("add");
btnAdd.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
if(state==false) {
first_pressed=e.getWhen();
state=true;
}
if(first_pressed!=e.getWhen())
{
JOptionPane.showConfirmDialog(null,"doubel click","Click",JOptionPane.YES_NO_OPTION);
state=false;
}
}
});

public class TestMouseListener implements MouseListener {
private boolean leftClick;
private int clickCount;
private boolean doubleClick;
private boolean tripleClick;
public void mouseClicked(MouseEvent evt) {
if (evt.getButton()==MouseEvent.BUTTON1){
leftClick = true; clickCount = 0;
if(evt.getClickCount() == 2) doubleClick=true;
if(evt.getClickCount() == 3){
doubleClick = false;
tripleClick = true;
}
Integer timerinterval = (Integer)Toolkit.getDefaultToolkit().getDesktopProperty("awt.multiClickInterval");
Timer timer = new Timer(timerinterval, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
if(doubleClick){
System.out.println("double click.");
clickCount++;
if(clickCount == 2){
doubleClick(); //your doubleClick method
clickCount=0;
doubleClick = false;
leftClick = false;
}
}else if (tripleClick) {
System.out.println("Triple Click.");
clickCount++;
if(clickCount == 3) {
tripleClick(); //your tripleClick method
clickCount=0;
tripleClick = false;
leftClick = false;
}
} else if(leftClick) {
System.out.println("single click.");
leftClick = false;
}
}
});
timer.setRepeats(false);
timer.start();
if(evt.getID()==MouseEvent.MOUSE_RELEASED) timer.stop();
}
}
public static void main(String[] argv) throws Exception {
JTextField component = new JTextField();
component.addMouseListener(new TestMouseListener());
JFrame f = new JFrame();
f.add(component);
f.setSize(300, 300);
f.setVisible(true);
component.addMouseListener(new TestMouseListener());
}
}

Java swing: selecting/deselecting JButton to imitate pulsing

f.e. I have an email client, it receives new message, button with incoming messages starts doing something, until user clicks it to see whats up.
I'm trying to make button attract attention by selecting, waiting and then deselecting it, but this does nothing!
do{
button.setSelected(true);
Thread oThread = new Thread() {
#Override
public void run() {
synchronized (this) {
try {
wait(1000);
} catch (InterruptedException e1) {
e1.printStackTrace();
}
}
button.setSelected(false);
}
};
oThread.start();
}while(true);

You should use Swing timers for that. Don't interact with GUI objects from foreign threads.
There's some docs in the Java tutorial: How to use Swing timers.
Here's an example way you could do this playing with the button's icon.
// member var
Icon buttonIcon;
Timer timer;
// in constructor for example
buttonIcon = new ImageIcon("resources/icon.png");
button.setIcon(buttonIcon);
timer = new Timer(1000, this);
timer.start();
// in the actionPerformed handler
if (button.getIcon() == null)
button.setIcon(icon);
else
button.setIcon(null);
Your class will need to implement ActionListener for this to work like that. Add some logic to stop the flashing when you need it.

hafl_workaround to your questions
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ShakingButtonDemo implements Runnable {
private JButton button;
private JRadioButton radioWholeButton;
private JRadioButton radioTextOnly;
public static void main(String[] args) throws Exception {
SwingUtilities.invokeLater(new ShakingButtonDemo());
}
#Override
public void run() {
radioWholeButton = new JRadioButton("The whole button");
radioTextOnly = new JRadioButton("Button text only");
radioWholeButton.setSelected(true);
ButtonGroup bg = new ButtonGroup();
bg.add(radioWholeButton);
bg.add(radioTextOnly);
button = new JButton(" Shake with this Button ");
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
shakeButton(radioWholeButton.isSelected());
}
});
JPanel p1 = new JPanel();
p1.setBorder(BorderFactory.createTitledBorder("Shake Options"));
p1.setLayout(new GridLayout(0, 1));
p1.add(radioWholeButton);
p1.add(radioTextOnly);
JPanel p2 = new JPanel();
p2.setLayout(new GridLayout(0, 1));
p2.add(button);
JFrame frame = new JFrame();
frame.setTitle("Shaking Button Demo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(p1, BorderLayout.NORTH);
frame.add(p2, BorderLayout.SOUTH);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private void shakeButton(final boolean shakeWholeButton) {
final Point point = button.getLocation();
final Insets margin = button.getMargin();
final int delay = 75;
Runnable r = new Runnable() {
#Override
public void run() {
for (int i = 0; i < 30; i++) {
try {
if (shakeWholeButton) {
moveButton(new Point(point.x + 5, point.y));
Thread.sleep(delay);
moveButton(point);
Thread.sleep(delay);
moveButton(new Point(point.x - 5, point.y));
Thread.sleep(delay);
moveButton(point);
Thread.sleep(delay);
} else {// text only
setButtonMargin(new Insets(margin.top, margin.left + 3, margin.bottom, margin.right - 2));
Thread.sleep(delay);
setButtonMargin(margin);
Thread.sleep(delay);
setButtonMargin(new Insets(margin.top, margin.left - 2, margin.bottom, margin.right + 3));
Thread.sleep(delay);
setButtonMargin(margin);
Thread.sleep(delay);
}
} catch (InterruptedException ex) {
ex.printStackTrace();
}
}
}
};
Thread t = new Thread(r);
t.start();
}
private void moveButton(final Point p) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
button.setLocation(p);
}
});
}
private void setButtonMargin(final Insets margin) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
button.setMargin(margin);
}
});
}
}

Swing rendering problem of busy cursors when using modal dialogs on Linux

When setting a busy cursor on the glass pane of the application frame after closing a modal dialog, the busy cursor is not always displayed. Sometimes it works (the first time it is mostly always working), sometimes not.
Even better, when setting the busy cursor before opening the dialog. The busy cursor get displayed but when moving the mouse inside and then outside the dialog the busy cursor is not displayed anymore.
Note that I observe the following bug on Linux only. On Mac OS X or Windows the behavior is deterministic and consistent.
Another hint, in the first case of the code sample, when the mouse is NOT entering the dialog and the YES_OPTION is selected using the keyboard, the busy mouse cursor is always shown. Also in this case, the "Please wait..." label on the glass pane get never painted.
Here a SSCCE demonstrating these bugs:
import java.awt.event.*;
import javax.swing.*;
public class TestFrame extends JFrame {
private JPanel panel;
private JPanel glassPane;
public TestFrame() {
final JButton button1 = new JButton(new AbstractAction("Start activity indicator after closing the dialog") {
#Override
public void actionPerformed(ActionEvent e) {
doAction1();
}
});
final JButton button2 = new JButton(new AbstractAction("Start activity indicator before opening the dialog") {
#Override
public void actionPerformed(ActionEvent e) {
doAction2();
}
});
panel = new JPanel();
panel.add(button1);
panel.add(button2);
getContentPane().add(panel, BorderLayout.NORTH);
glassPane = (JPanel) getGlassPane();
glassPane.setLayout(new BorderLayout());
glassPane.setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
glassPane.add(new JLabel("Please Wait..."), BorderLayout.CENTER);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(800, 600);
setVisible(true);
}
public void doAction1() {
System.out.println("IsStartingInEDT?: "+ SwingUtilities.isEventDispatchThread());
final int response = JOptionPane.showConfirmDialog(this, "Click on the YES_OPTION, busy indicator must start (if it does, try again).");
if (JOptionPane.YES_OPTION == response) {
startActivity();
for (int i = 0; i < 5; i++) {
try {
Thread.sleep(200);
} catch (Exception e) {
e.printStackTrace();
}
}
stopActivity();
}
}
public void doAction2() {
startActivity();
System.out.println("IsStartingInEDT?: "+ SwingUtilities.isEventDispatchThread());
final int response = JOptionPane.showConfirmDialog(this, "Move the mouse inside the dialog (me) and then outside, the busy indicator is not shown anymore");
if (JOptionPane.YES_OPTION == response) {
for (int i = 0; i < 5; i++) {
try {
Thread.sleep(200);
} catch (Exception e) {
e.printStackTrace();
}
}
}
stopActivity();
}
public void startActivity() {
System.out.println("TestFrame.startActivity()");
glassPane.setVisible(true);
}
public void stopActivity() {
System.out.println("TestFrame.stopActivity()");
glassPane.setVisible(false);
}
/**
* #param args
*/
public static void main(String[] args) {
new TestFrame();
}
}
At the moment I did not find any related issues in the JavaBug parade. I will search further before opening a new one.
I also already read the following article but it is not very convenient as making a good modal dialog from a non-modal one is not straightforward:
http://www.javaspecialists.eu/archive/Issue065.html
Can anyone provide some help?
Thanks in advance, Pierre

You have some threading issue here.
Is IsStartingInEDT true?
If yes, you are doing it wrong because:
You should not sleep in UI thread. This would stop the screen update.
If no, you are doing it wrong because:
OptionPane.showConfirmDialog() must be called from the UI thread.
you should do something like this:
public void doAction1() {
if (!SwingUtilities.isEventDispatchThread()) {
System.err.println("error, must be edt");
return;
}
final int response = JOptionPane.showConfirmDialog(this, "Click on the YES_OPTION, busy indicator must start (if it does, try again).");
if (JOptionPane.YES_OPTION == response) {
startActivity(); // change glass panel in edt
// new thread for long standing task
new Thread( new Runnable() { public void run() {
for (int i = 0; i < 5; i++) {
try {
Thread.sleep(200);
} catch (Exception e) {
e.printStackTrace();
}
}
SwingUtilities.invokeAndWait(new Runnable(){ public void run() {
// changing glass panel need edt
stopActivity();
});
}).start();
}
}

1st. by using Tread.sleep(int) pretty sure to block EDT, with all issues desribed about Concurrency in Swing
2.nd works because initializations for JOptionPane create a new EDT
here is simple demonstrations about ...., please that only example and be sure that is against all Swing rules, but demostrated lock and unlock EDT by usage Tread.sleep(int) during EDT
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
public class ShakeComponents1 {
private JFrame frame = new JFrame();
private final String items[] = {"One", "Two", "Three"};
private Timer timer;
private JPanel panel = new JPanel();
private JPanel buttonPanel = new JPanel();
private JButton button = new JButton(" Exit ");
private boolean repeats = true;
private boolean runs = false;
private Color clr[] = {Color.red, Color.blue, Color.magenta};
private Insets initMargin;
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new ShakeComponents1().makeUI();
}
});
}
public void makeUI() {
buttonPanel = new JPanel();
buttonPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
buttonPanel.setLayout(new BorderLayout());
button.setPreferredSize(new Dimension(100, 45));
button.setForeground(Color.darkGray);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
Runnable doRun = new Runnable() {
#Override
public void run() {
System.exit(0);
}
};
SwingUtilities.invokeLater(doRun);
}
});
button.addMouseListener(new java.awt.event.MouseListener() {
#Override
public void mouseClicked(MouseEvent e) {
}
#Override
public void mousePressed(MouseEvent e) {
}
#Override
public void mouseReleased(MouseEvent e) {
}
#Override
public void mouseEntered(MouseEvent e) {
if (runs) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
runs = false;
timer.stop();
changePnlBorder(new EmptyBorder(5, 5, 5, 5));
changeBtnForegroung(Color.darkGray);
}
});
}
}
#Override
public void mouseExited(MouseEvent e) {
if (!runs) {
timer.start();
runs = true;
}
}
});
buttonPanel.add(button);
final Insets margin = button.getMargin();
panel.add(buttonPanel);
for (int i = 0; i < 2; i++) {
JComboBox combo = new JComboBox(items);
combo.setMinimumSize(new Dimension(50, 25));
combo.setMaximumSize(new Dimension(150, 25));
combo.setPreferredSize(new Dimension(100, 25));
combo.addActionListener(new ShakeAction());
panel.add(combo);
}
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(panel);
frame.pack();
frame.setLocation(50, 50);
frame.setVisible(true);
timer = new Timer(500, new ShakeAction());
timer.setRepeats(repeats);
initMargin = button.getMargin();
}
private class ShakeAction extends AbstractAction {
private static final long serialVersionUID = 1L;
private int noColor = 0;
private Border border;
private int count = 0;
#Override
public void actionPerformed(ActionEvent e) {
timer.start();
if (count > 5) {
new Thread(new Runnable() {
#Override
public void run() {
try {
Thread.sleep(500);
changeBtnForegroung(Color.darkGray);
Thread.sleep(500);
count = 0;
Thread.sleep(750);
} catch (Exception e) {
System.out.println(e);
}
}
}).start();
} else {
new Thread(new Runnable() {
#Override
public void run() {
try {
runs = true;
if (noColor < 2) {
noColor++;
changeBtnForegroung(clr[noColor]);
} else {
noColor = 0;
changeBtnForegroung(clr[noColor]);
}
changeBtnMargin(new Insets(initMargin.top, initMargin.left + 10, initMargin.bottom, initMargin.right - 10));
border = new EmptyBorder(0, 5, 10, 5);
changePnlBorder(border);
Thread.sleep(100);
changeBtnMargin(new Insets(initMargin.top, initMargin.left - 10, initMargin.bottom, initMargin.right + 10));
border = new EmptyBorder(0, 0, 10, 10);
changePnlBorder(border);
Thread.sleep(100);
changeBtnMargin(new Insets(initMargin.top, initMargin.left + 10, initMargin.bottom, initMargin.right - 10));
border = new EmptyBorder(5, 10, 5, 0);
changePnlBorder(border);
Thread.sleep(100);
changeBtnMargin(new Insets(initMargin.top, initMargin.left - 10, initMargin.bottom, initMargin.right + 10));
border = new EmptyBorder(10, 10, 0, 0);
changePnlBorder(border);
Thread.sleep(100);
changeBtnMargin(new Insets(initMargin.top, initMargin.left, initMargin.bottom, initMargin.right));
border = new EmptyBorder(5, 5, 5, 5);
changePnlBorder(border);
Thread.sleep(100);
count++;
} catch (Exception e) {
System.out.println(e);
}
}
}).start();
}
}
}
private void changePnlBorder(final Border b) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
buttonPanel.setBorder(b);
buttonPanel.revalidate();
buttonPanel.repaint();
}
});
}
private void changeBtnForegroung(final Color c) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
button.setForeground(c);
}
});
}
private void changeBtnMargin(final Insets margin) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
button.setMargin(margin);
}
});
}
}
conclusion -> you can create new Thread as BackGroung Task(s) wrapped into Runnable, if you wnat to simulate LongRunning Task and with Thread.sleep(int), maybe answer to your question is here
sure correct way would be by using SwingWorker for that, with Thread.sleep(int) too