Question

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);

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.