Java JProgressBar使用Image

我正在用Java制作游戏，我正在使用JProgressBar作为健康栏。 我想为JProgressBar使用图像（而不是颜色），但我无法做到。 我已经尝试使用paint方法， paintComponent方法，创建一个新类，但它不起作用。 愿有人请帮帮我吗？

Answer 1

无需创建自己的ProgressBarUI实现，您只需创建自己的…

该示例基本上从单个部分图像中产生“魔药条”，然后基于当前进度渲染子图像。

它只需要显示整个魔药就不会花太多时间……

 import java.awt.Color; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.FontMetrics; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.GridBagLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.image.BufferedImage; import java.io.IOException; import java.text.NumberFormat; import javax.imageio.ImageIO; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.Timer; import javax.swing.UIManager; import javax.swing.UnsupportedLookAndFeelException; public class ProgressPane { public static void main(String[] args) { new ProgressPane(); } public ProgressPane() { 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.setLayout(new GridBagLayout()); frame.add(new TestPane()); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } }); } public class TestPane extends JPanel { private float progress = 1f; private BufferedImage potion; private BufferedImage potionBar; public TestPane() { try { potion = ImageIO.read(getClass().getResource("/Potion.png")); } catch (IOException ex) { ex.printStackTrace(); } setOpaque(false); setForeground(Color.BLUE); setBackground(Color.GRAY); Timer timer = new Timer(500, new ActionListener() { @Override public void actionPerformed(ActionEvent e) { progress -= 0.01; if (progress <= 0.001) { ((Timer) e.getSource()).stop(); } repaint(); } }); timer.setRepeats(true); timer.setCoalesce(true); timer.start(); } @Override public void invalidate() { super.invalidate(); potionBar = null; } @Override public Dimension getPreferredSize() { FontMetrics fm = getFontMetrics(getFont()); return new Dimension(200, Math.max(50, fm.getHeight() + 4)); } protected void createPotionBar() { if (potionBar == null) { if (getWidth() > 0 && getHeight() > 0) { FontMetrics fm = getFontMetrics(getFont()); int height = Math.max(50, fm.getHeight() + 4); potionBar = new BufferedImage(getWidth() - 4, height, BufferedImage.TYPE_INT_ARGB); Graphics2D g2d = potionBar.createGraphics(); int x = 0; int y = (height - potion.getHeight()) / 2; while (x < getWidth() - 4) { g2d.drawImage(potion, x, y, this); x += potion.getWidth(); } g2d.dispose(); } } } @Override protected void paintComponent(Graphics g) { createPotionBar(); super.paintComponent(g); int width = getWidth() - 4; int height = getHeight() - 4; int x = 2; int y = 2; g.setColor(getBackground()); g.fillRect(x, y, width, height); g.setColor(Color.BLACK); g.drawRect(x, y, width, height); int progressWidth = (int) (width * progress); BufferedImage progressImage = potionBar.getSubimage(0, 0, progressWidth, potionBar.getHeight()); g.drawImage(progressImage, x, y, this); FontMetrics fm = g.getFontMetrics(); String value = NumberFormat.getPercentInstance().format(progress); x = x + ((width - fm.stringWidth(value)) / 2); y = y + ((height - fm.getHeight()) / 2); g.setColor(Color.WHITE); g.drawString(value, x, y + fm.getAscent()); } } }