我在Java中使用JProgressBars的时间不长，并且我看到的将其设置为漂亮的所有资源均无法使用。我想要的是在应用程序上，您将看到整个进度条从上到下填充，并且当值增加时，动画将随着大小的增加而播放。我目前拥有的是JProgressBar，当它的值增加时，它没有动画，并且当它的偏移量移到右上角时，如下所示：
如您所见，这很丑陋。我怎样才能看到整个边框，整个填充以及JProgressBar的动画？
最佳答案
关于以任何有意义的方式修改JProgressBar的唯一方法是设计自己的UI委托...
这基本上是一个基于我很久以前所做的工作的示例。
该示例以25的增量更新进度条，但是进度条“尝试”以较小的增量从其当前位置填充到目标值。
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagLayout;
import java.awt.LinearGradientPaint;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Point2D;
import java.awt.geom.RoundRectangle2D;
import javax.swing.BoundedRangeModel;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.swing.plaf.basic.BasicProgressBarUI;
public class TestMediaProgressBar {
public static void main(String[] args) {
new TestMediaProgressBar();
}
public TestMediaProgressBar() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private MediaProgressBar pb;
private int value = 0;
private int delta = 25;
public TestPane() {
setBackground(Color.BLACK);
setLayout(new GridBagLayout());
pb = new MediaProgressBar();
add(pb);
Timer timer = new Timer(500, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (value + delta > 100) {
delta *= -1;
value = 100;
} else if (value + delta < 0) {
delta *= -1;
value = 0;
}
value += delta;
pb.setValue(value);
}
});
timer.start();
}
@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
public class MediaProgressBar extends JProgressBar {
public MediaProgressBar() {
setUI(new MediaProgressBarUI());
}
@Override
public Dimension getPreferredSize() {
return new Dimension(128, 24);
}
}
public class MediaProgressBarUI extends BasicProgressBarUI {
private Handler handler;
private double renderProgress = 0;
private double targetProgress = 0;
private double progressDelta = 0.04;
private Timer repaintTimer;
private Timer paintTimer;
public MediaProgressBarUI() {
repaintTimer = new Timer(25, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
progressBar.repaint();
}
});
repaintTimer.setRepeats(false);
repaintTimer.setCoalesce(true);
paintTimer = new Timer(40, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if (progressDelta < 0) {
if (renderProgress + progressDelta < targetProgress) {
((Timer) e.getSource()).stop();
renderProgress = targetProgress + progressDelta;
}
} else {
if (renderProgress + progressDelta > targetProgress) {
((Timer) e.getSource()).stop();
renderProgress = targetProgress - progressDelta;
}
}
renderProgress += progressDelta;
requestRepaint();
}
});
}
protected void requestRepaint() {
repaintTimer.restart();
}
@Override
protected void installDefaults() {
super.installDefaults();
progressBar.setOpaque(false);
progressBar.setBorder(null);
}
public void setRenderProgress(double value) {
if (value != targetProgress) {
paintTimer.stop();
targetProgress = value;
if (targetProgress < renderProgress && progressDelta > 0) {
progressDelta *= -1;
} else if (targetProgress > renderProgress && progressDelta < 0) {
progressDelta *= -1;
}
System.out.println(progressDelta);
paintTimer.start();
}
}
public double getRenderProgress() {
return renderProgress;
}
@Override
public void paint(Graphics g, JComponent c) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int iStrokWidth = 3;
g2d.setStroke(new BasicStroke(iStrokWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
g2d.setColor(c.getBackground());
g2d.setBackground(c.getBackground());
int width = c.getWidth();
int height = c.getHeight();
RoundRectangle2D outline = new RoundRectangle2D.Double((iStrokWidth / 2), (iStrokWidth / 2),
width - iStrokWidth, height - iStrokWidth,
height, height);
g2d.draw(outline);
int iInnerHeight = height - (iStrokWidth * 4);
int iInnerWidth = width - (iStrokWidth * 4);
iInnerWidth = (int) Math.round(iInnerWidth * renderProgress);
int x = iStrokWidth * 2;
int y = iStrokWidth * 2;
Point2D start = new Point2D.Double(x, y);
Point2D end = new Point2D.Double(x, y + iInnerHeight);
float[] dist = {0.0f, 0.25f, 1.0f};
Color[] colors = {c.getBackground(), c.getBackground().brighter(), c.getBackground().darker()};
LinearGradientPaint p = new LinearGradientPaint(start, end, dist, colors);
g2d.setPaint(p);
RoundRectangle2D fill = new RoundRectangle2D.Double(iStrokWidth * 2, iStrokWidth * 2,
iInnerWidth, iInnerHeight, iInnerHeight, iInnerHeight);
g2d.fill(fill);
g2d.dispose();
}
@Override
protected void installListeners() {
super.installListeners();
progressBar.addChangeListener(getChangeHandler());
}
protected ChangeListener getChangeHandler() {
return getHandler();
}
protected Handler getHandler() {
if (handler == null) {
handler = new Handler();
}
return handler;
}
protected class Handler implements ChangeListener {
@Override
public void stateChanged(ChangeEvent e) {
BoundedRangeModel model = progressBar.getModel();
int newRange = model.getMaximum() - model.getMinimum();
double dProgress = (double) (model.getValue() / (double) newRange);
if (dProgress < 0) {
dProgress = 0;
} else if (dProgress > 1) {
dProgress = 1;
}
setRenderProgress(dProgress);
}
}
}
}
关于java - Java:制作漂亮的JProgressBar，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/20136505/