JProgressBar 不会在循环内实时更新 [重复]

Question

这是我第一次使用进度条，我遇到了一个问题，除了我尝试从任何地方调用它的setValue(x)，它保持在 0% 并在我的方法例程之后直接进入 100%完成。

我尝试创建一个扩展 Thread 的内部类，然后在我尝试在我的“main”方法中启动一个新 Thread 之后，最后我尝试使用 Observer。这些似乎根据这篇文章有效，但不幸的是对我来说不是

Update JProgressBar from new Thread

Problem making a JProgressBar update values in Loop (Threaded)

请问有人可以帮我吗？？？

public class MainClass {      

private void checkFiles() {

    Task task = new Task();
    task.start();

    //here I have some Files validation...I don't think it is important to solve the progressbar problem 
    //so it will be ommited


    //in this point I tried to call update to test the observer solution I found in another post here
    //task.update(null, null);

    JOptionPane.showMessageDialog(this, "Done!");
    //here the bar jumps from 0% to 100%

    }


    private class Task extends Thread implements Observer {

    public Task() {
    }

    //Dont bother with the calculum as I haven't finished working on them....
    //The relevant thing here is that it starts a new Thread and I can see the progress
    //increasing on console using system.out but my progress bar still don't change from 0%.
    public void run() {
        int maxSize = 100;
        final int partsSize = maxSize / listaArquivosSelecionados.size();
        while (listFilesValidated.size() != listFilesToValidate.size()) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
            int progress = listFilesValidated.size() * partsSize;
            System.out.println("Progress" + progress);
            progressBar.setValue(progress);

            }
        });
        try {
            Thread.sleep(100);
        }
        catch (InterruptedException e) {}
        }
    }

    //Just tried to set any value to check if it would update before the files validation thread finishes its work.
    @Override
    public void update(Observable arg0, Object arg1) {
        progressBar.setValue(66);
    }
}

Answer 1

您可以创建另一个 ProgressBar 类（请参阅Oracle tutorial）并使用它：

ProgressBar pbFrame = new ProgressBar();
pbFrame.setVisible(true);       
Executors.newSingleThreadExecutor().execute(new Runnable() {
        @Override
        public void run() {
            // run background process

        }
    });

也可以使用SwingWorker，例如：

SwingWorker worker = new SwingWorker<MyReturnType, Void>() {
    @Override
    public MyReturnType doInBackground() {
        // do your calculation and return the result. Change MyReturnType to whatever you need
    }
    @Override
    public void done() {
        // do stuff you want to do after calculation is done
    }
};

几年前我有the same question。