我正在尝试使用 Java 进行小型图像处理。用户应该能够加载图像并通过单击按钮对图像进行一些简单的修改。加载和显示图像没有问题,但是当我尝试从中制作二进制图像时, repaint() 方法使我在屏幕上显示为黑色图像。我认为问题出在 repaint() 方法上。我已经使用了搜索功能和谷歌,但我仍然不知道我的代码有什么问题。这就是我到目前为止所拥有的:
public class ImageProcessing extends JFrame implements ActionListener {
private JPanel imagePanel;
private JPanel buttonPanel;
private JButton binaryButton;
private JButton loadButton;
private BufferedImage image;
private final String WINDOW_TITLE = "Image Processing";
public ImageProcessing() {
createWindow();
}
private void createWindow() {
this.setTitle(WINDOW_TITLE);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setSize(500, 500);
imagePanel = new ImagePanel();
buttonPanel = new JPanel();
this.add(imagePanel, BorderLayout.CENTER);
loadButton = new JButton("Load image");
loadButton.addActionListener(this);
buttonPanel.add(loadButton);
this.add(buttonPanel, BorderLayout.SOUTH);
binaryButton = new JButton("binary");
binaryButton.addActionListener(this);
buttonPanel.add(binaryButton);
this.setVisible(true);
}
@Override
public void actionPerformed(ActionEvent e) {
if(e.getSource() == this.loadButton) {
String filePath = getImageFile();
if (filePath != null) {
try {
image = ImageIO.read(new File(filePath));
// imageBackup = image;
} catch (IOException e1) {
e1.printStackTrace();
}
this.repaint();
}
} else if (e.getSource() == this.binaryButton) {
image = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_BYTE_BINARY);
imagePanel = new ImagePanel();
this.repaint();
}
}
private String getImageFile() {
JFileChooser chooser = new JFileChooser();
int result = chooser.showOpenDialog(null);
File file = null;
if (result == JFileChooser.APPROVE_OPTION) {
file = chooser.getSelectedFile();
return file.getPath();
} else
return null;
}
class ImagePanel extends JPanel {
public void paint(Graphics g) {
g.drawImage(image, 0, 0, this);
}
}
}
我希望你能帮助我并解释我做错了什么。提前致谢。