java - 进度条 % 文本

Question

所以我在 Java 教程中使用了：ProgressBarDemo.java。我将如何继续添加

if 20% {
taskOutput.append(String.format("Completed %d%% of task.\n", task.getProgress()));
if 40% {
taskOutput.append(String.format("Completed %d%% loading region.\n", task.getProgress()));
if 60% {
taskOutput.append(String.format("Completed %d%% loading maps.\n", task.getProgress()));

etc...

封装组件；

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.beans.*;
import java.util.Random;

public class ProgressBarDemo extends JPanel implements ActionListener, PropertyChangeListener {

    private JProgressBar progressBar;
    private JButton startButton;
    private JTextArea taskOutput;
    private Task task;

    class Task extends SwingWorker<Void, Void> {
        @Override
        public Void doInBackground() {
            Random random = new Random();
            int progress = 0;
            setProgress(0);
            while (progress < 100) {
                try {
                    Thread.sleep(random.nextInt(1000));
                } catch (InterruptedException ignore) {}
                progress += random.nextInt(10);
                setProgress(Math.min(progress, 100));
            }
            return null;
        }

        @Override
        public void done() {
            Toolkit.getDefaultToolkit().beep();
            startButton.setEnabled(true);
            setCursor(null);
            taskOutput.append("Finished loading WorldPlay!\n");
        }
    }

    public ProgressBarDemo() {
        super(new BorderLayout());

        startButton = new JButton("Start");
        startButton.setActionCommand("start");
        startButton.addActionListener(this);

        progressBar = new JProgressBar(0, 100);
        progressBar.setValue(0);
        progressBar.setStringPainted(true);

        taskOutput = new JTextArea(5, 20);
        taskOutput.setMargin(new Insets(5,5,5,5));
        taskOutput.setEditable(false);

        JPanel panel = new JPanel();
        panel.add(startButton);
        panel.add(progressBar);

        add(panel, BorderLayout.PAGE_START);
        add(new JScrollPane(taskOutput), BorderLayout.CENTER);
        setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));

    }

    public void actionPerformed(ActionEvent evt) {
        startButton.setEnabled(false);
        setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
        task = new Task();
        task.addPropertyChangeListener(this);
        task.execute();
    }

    public void propertyChange(PropertyChangeEvent evt) {
        if ("progress" == evt.getPropertyName()) {
            int progress = (Integer) evt.getNewValue();
            progressBar.setValue(progress);
            taskOutput.append(String.format("Completed %d%% of task.\n", task.getProgress()));
        } 
    }

    private static void createAndShowGUI() {
        JFrame frame = new JFrame("WorldPlay");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JComponent newContentPane = new ProgressBarDemo();
        newContentPane.setOpaque(true);
        frame.setContentPane(newContentPane);

        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
}