Java swing: selecting/deselecting JButton to imitate pulsing

Question

fe 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);

Answer 1

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.

Answer 2

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);
            }
        });
    }
}