问题
I want to show a progress in pie format. Can anyone help? I have the data to show, but how to show it in this format. Something like progress shown in Google Chrome when we download files.
回答1:
Based on the links provided by @trashgod, here is one way you can achieve a "Pie" effect. This only handles the indeterminate progress bar, but it would be very easy to add the "determinate" behaviour.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.plaf.basic.BasicProgressBarUI;
/** @see http://stackoverflow.com/questions/8884297 */
public class ProgressBarUITest extends JPanel {
public ProgressBarUITest() {
super(new BorderLayout());
JProgressBar jpb = new JProgressBar();
jpb.setUI(new MyProgressUI());
jpb.setForeground(Color.GRAY);
jpb.setIndeterminate(true);
this.add(jpb);
}
private static class MyProgressUI extends BasicProgressBarUI {
private static final int ARC_EXTENT = 25;
@Override
protected void installDefaults() {
super.installDefaults();
progressBar.setBorder(null);
}
@Override
protected void paintIndeterminate(Graphics g, JComponent c) {
int angle = (int) (90 - 360.0 * getAnimationIndex() / getFrameCount());
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.setColor(progressBar.getForeground());
int size = Math.min(c.getWidth(), c.getHeight());
g2d.fillArc((c.getWidth() - size) / 2, (c.getHeight() - size) / 2, size, size, angle - ARC_EXTENT, ARC_EXTENT);
}
@Override
protected Rectangle getBox(Rectangle r) {
if (r != null) {
r.setBounds(progressBar.getBounds());
return r;
}
return progressBar.getBounds();
}
@Override
public Dimension getPreferredSize(JComponent c) {
return new Dimension(100, 100);
}
}
private void display() {
JFrame f = new JFrame("ProgressBarUITest");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(this);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
new ProgressBarUITest().display();
}
});
}
}
来源:https://stackoverflow.com/questions/16331331/java-swing-show-progress-in-pie-form