如何丢弃/合并重复的AWT事件？

Question

When a user does some action (such as click a button), I need to display the status in the JLabel. This status needs to disappear after 2 seconds. I use the following for that.

Timer timer = new Timer(2000, new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
                label.setVisible(false);
        }
    });

However, it is possible that the user clicks the button many times and this timer is triggered multiple times. This has an undesirable effect. When a button is clicked 3 times for instances.

0th second: 1st click : label disppear at 2nd second

1st second: 2nd click : label disppear at 3rd second

2nd second: 3rd click : label disppear at 4th second

Here, the label needs to disappear after the 4th second but will disappear after 2nd second. Therefore, I want this label to be hidden with a delay of 2s after only the last event

To handle this, I use an atomic counter.

AtomicInteger counter = new AtomicInteger(0);

Each task is given a unique 'taskCounter' using counter.incrementAndGet()

.

  Timer timer = new Timer(5000, new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            if (counter.get() == taskCounter) {
                infoLabel.setVisible(false);
            }
        }
    });
    timer.start();

The above is only executed if it is the last event that has been triggered. Ensuring that, my label stays visible at least 2 seconds after the last event.

Is there a better way of dealing with this problem?

Answer 1

Given two instances of java.swing.Timer , let t1 fire at some some nominal rate that is less than two seconds. Let the ActionListener for t1 update the label and invoke restart() on t2 , which should have an initial delay of two seconds. Let the ActionListener for t2 stop() itself and invoke label.setVisible(false) .