Java6学习笔记15——利用Swing创建不知道执行长度的任务的等待进度条

import javax.swing.JFrame;
import javax.swing.JProgressBar;
import java.awt.Container;
import java.awt.Insets;
import java.awt.Dimension;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class ProgIndDemo extends JFrame {
public static void main(String arg[]) {
new ProgIndDemo();
}
public ProgIndDemo() {
int height;
int width;
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e)
{ System.exit(0); } } );

setLocation(200,150);
Container pane = getContentPane();
pane.setLayout(null);
Insets insets = pane.getInsets();

JProgressBar bar = new JProgressBar(0,100);//创建进度条
bar.setIndeterminate(true);//值为 true 意味着不确定，而值为 false 则意味着普通或者确定。

Dimension dim = bar.getPreferredSize();
int x = insets.left + 20;
int y = insets.top + 20;
dim.width += 100;
bar.setBounds(x,y,dim.width,dim.height);
pane.add(bar);

width = x + dim.width + 20 + insets.left;
height = y + dim.height + 40 + insets.bottom;

setSize(width,height);
setVisible(true);
}
}