The setProgress() API notes: “For performance purposes all these invocations are coalesced into one invocation with the last invocation argument only.” Adding Thread.sleep(1) simply defers the coalescence; invoking println() introduces a comparable delay. Take heart that your file system is so fast; I would be reluctant to introduce an artificial delay. As a concrete example … Read more
SwingWorker is a lot simpler to use them it might seem. Basically, you need to make a few basic decisions about what you want to achieve. Do you want to return periodically updates while the process is running or Do you want to return a result of the process…or both? Do you want to provide … Read more
I know the way I use swingworker is wrong! I dont know how to fix it Before start I have some tips: Get rid of the arrays: you have several of them and you’ll see they only mess the things up because you’ll need indexes and loops everywhere to work with them and it’s too … Read more
Because your background thread is devoted entirely to watching, take() is the right choice. It effectively hides the platform dependent implementation, which may either forward or poll. One of the poll() methods would be appropriate if, for example, your background thread also needed to examine other queues in series with the WatchService. Addendum: Because the … Read more
Consider using a JList for the right panel to take advantage of the flexible layout options and selection handling, as shown here and below. import java.awt.Component; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.GridLayout; import java.awt.RenderingHints; import java.awt.image.BufferedImage; import javax.swing.BorderFactory; import javax.swing.DefaultListCellRenderer; import javax.swing.DefaultListModel; import javax.swing.Icon; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JList; import … Read more
Here’s a VERY basic example. Basically, because you program requires asynchronous communications (that is, you need to be able to read from the socket AND write to it at the same time), you need to offload each stream to a separate thread. The management process of this example is, well, no existent. Realistically, you should … Read more
The main problem you’re having is you’re trying to perform blocking actions in the Event Dispatching Thread. This will prevent the UI from been updated as repaint requests are not reaching the repaint manager until AFTER you’ve finished. To over come this, you’re going to need to off load the blocking work (ie the back … Read more
SHORT ANSWER: This happens because publish() doesn’t directly schedule process, it sets a timer which will fire the scheduling of a process() block in the EDT after DELAY. So when the worker is cancelled there is still a timer waiting to schedule a process() with the data of the last publish. The reason for using … Read more
It turns out SwingWorker posts instances of Runnable to the EventQueue using a javax.swing.Timer with exactly that DELAY. private static class DoSubmitAccumulativeRunnable extends AccumulativeRunnable<Runnable> implements ActionListener { private final static int DELAY = (int) (1000 / 30); … } You can get a higher frame rate, but not with javax.swing.SwingWorker. You can build SwingWorker from … Read more
There is an excellent example from the JavaDocs class PrimeNumbersTask extends SwingWorker<List<Integer>, Integer> { PrimeNumbersTask(JTextArea textArea, int numbersToFind) { //initialize } @Override public List<Integer> doInBackground() { List<Integer> numbers = new ArrayList<Integer>(25); while (!enough && !isCancelled()) { number = nextPrimeNumber(); numbers.add(number); publish(number); setProgress(100 * numbers.size() / numbersToFind); } return numbers; } @Override protected void process(List<Integer> chunks) … Read more