Java上传百分比progressbar线程 [英] Java uploading percentage progressbar thread

问题描述

我正在开发一个java应用程序，其中我使用bufferedInputStream保存大文件。
我在JDialog里面放了一个progressbar，它表示上传的文件的百分比，并且每n秒增加一个。
问题是应用程序无限期地等待对话框关闭，因此它永远不会退出。
任何人都可以帮助？

I'm developing a java application where I save big files using bufferedInputStream. I have put a progressbar inside a JDialog which indicates the percentage of uploaded files and which increases every n seconds. The problem is that the application waits indefinitely for the dialog to close and so it never exits. Anyone can help?

这里是主要的应用程序片段：

here is the main application snippet:

JDialog dialog = new JDialog(Main.getMainFrame(), true);
                    ProgressBarJPanel progressBarJPanel = new ProgressBarJPanel();
                    dialog.setContentPane(progressBarJPanel);
                    dialog.pack();
                    dialog.setVisible(true);
                    while ((val = bufferedInputStream.read()) != -1)
                    {
                        fileOutputStream.write(val);
                    }
                    progressBarJPanel.end();
                    dialog.setVisible(false);

和所指的类别

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class ProgressBarJPanel extends JPanel
        implements ActionListener
{
    private JProgressBar progressBar;
    private Timer timer;
    public Thread updateThread;
    public final static int ONE_SECOND = 1000;
    private JTextArea taskOutput;
    private String newline = "\n";
    int timeNow= 0;
    int progress = 0;

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

        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);
        taskOutput.setCursor(null);

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

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

        //Create a timer.
        timer = new Timer(ONE_SECOND, new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent evt) {
                progressBar.setValue(progress);
                progress+=10;
                String s = "now at "+progress+"%";
                if (s != null) {
                    taskOutput.append(s + newline);
                    taskOutput.setCaretPosition(
                            taskOutput.getDocument().getLength());
                }
            }
        });

    }

    public void end()
    {
        timer.stop();
    }

    public void startProgress()
    {
        timer.start();
    }

    /**
     * Create the GUI and show it. For thread safety, this method should be
     * invoked from the event-dispatching thread.
     */
    private static void createAndShowGUI()
    {
        //Make sure we have nice window decorations.
        JFrame.setDefaultLookAndFeelDecorated(true);

        //Create and set up the window.
        JFrame frame = new JFrame("ProgressBarDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        JComponent newContentPane = new ProgressBarJPanel();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args)
    {
                createAndShowGUI();
    }

    @Override
    public void actionPerformed(ActionEvent e)
    {
        throw new UnsupportedOperationException("Not supported yet.");
    }
}

- EDIT

这里是基于ben75建议的解决方案：

Here is the solution based on ben75 advice:

JDialog dialog = new JDialog(Main.getMainFrame(), true);
ProgressBarJPanel progressBarJPanel = new ProgressBarJPanel();
dialog.setContentPane(progressBarJPanel);
Runnable r = new Runnable(){
  public void run(){
             SwingUtilities.invokeLater(new Runnable()
             {
                    @Override
                    public void run()
                    {
                       progressBarJPanel.startProgress();
                       dialog.pack();
                       dialog.setVisible(true);
                    }
             });

            //this is the long running job
            while ((val = bufferedInputStream.read()) != -1)
            {
                fileOutputStream.write(val);
            }

            //here is the callback to UI thread
            SwingUtilities.invokeLater(new Runnable(){
                public void run(){
                    progressBarJPanel.end();
                    dialog.setVisible(false);
                }
           }
  };
Thread t = new Thread(r);
t.start();

推荐答案

在另一个线程（即非UI线程）中，并在作业回调结束时UI线程关闭对话框。

You must do time consumming jobs in another thread (i.e. non UI thread) and at the end of the job callback the UI thread to close the dialog.

或多或少如何编码： / p>

More or less how it can be coded:

JDialog dialog = new JDialog(Main.getMainFrame(), true);
ProgressBarJPanel progressBarJPanel = new ProgressBarJPanel();
dialog.setContentPane(progressBarJPanel);
dialog.pack();
dialog.setVisible(true);
Runnable r = new Runnable(){
      public void run(){
                //this is the long running job
                while ((val = bufferedInputStream.read()) != -1)
                {
                    fileOutputStream.write(val);
                }
                //here is the callback to UI thread
                SwingUtilities.invokeLater(new Runnable(){
                    public void run(){
                        progressBarJPanel.end();
                        dialog.setVisible(false);
                    }
               }
      };
Thread t = new Thread(r);
t.start();

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