Progress bar using for loop as simulation

Question

I am trying to simulate a progressbar process using a for loop. The whole loop represent 100% so as the loop increases, the progressbar should also increase until the loop is done it will be 100% However in netbean UI the progress bar doesnt show as expected.

    int i;
    progressBar.setStringPainted(true);
    for (i = 0; i < 99999; i++) {
        i = i;
        progressBar.setValue(i);
        System.out.println(i);
    }
    progressBar.updateUI();

What do you mean by "the progress bar doesn't show as expected"? Do you get an error? Also indent your code correctly and check if you have a closing-bracket in the `for` loop. — Christian Tapia, Dec 31 '13 at 04:51
Because you're blocking the UI thread with your loop, so it's not going to be updated until after you exit whatever method this is in. — Brian Roach, Dec 31 '13 at 04:55
please check it out ... http://stackoverflow.com/questions/7403729/how-to-use-jprogressbar — Tun Zarni Kyaw, Dec 31 '13 at 04:55
I have changed my codes a little, it shows a 100% now after completion, how do I progressively update the bar — BeyondProgrammer, Dec 31 '13 at 05:00
[How to use progressbars](http://docs.oracle.com/javase/tutorial/uiswing/components/progress.html) — Vincent Ramdhanie, Dec 31 '13 at 05:19

score 0 · Answer 1 · answered Dec 31 '13 at 05:05

you can't do that unless the progress bar is in it's own thread. Then you access the progress bar from a different thread, This is because the progress bar will not update until the for loop is entirely done in a single thread.

So, create a new thread with the gui in it.

score 0 · Answer 2 · answered Dec 31 '13 at 05:45

Try updating the progressBar UI just after setting value.

    int i;
    progressBar.setStringPainted(true);
    for (i = 0; i < 99999; i++) {
        i = i;
        progressBar.setValue(i);
        progressBar.updateUI();
        System.out.println(i);
    }

Progress bar using for loop as simulation

2 Answers2