我制作了一个应用程序，它从特定目录加载图像，在堆栈中加载所有图像，当我单击下一个按钮时，下一个图像加载。我还添加了 JSlider 来改变加载图像的亮度，但它不起作用。我不知道为什么，但我没有得到确切的问题。
我的代码：
public class PictureEditor extends JFrame
{
private static final long serialVersionUID = 6676383931562999417L;
String[] validpicturetypes = {"png", "jpg", "jpeg", "gif"};
Stack<File> pictures ;
JLabel label = new JLabel();
BufferedImage a = null;
float fval=1;
public PictureEditor()
{
JPanel panel = new JPanel();
JMenuBar menubar = new JMenuBar();
JMenu toolsmenu = new JMenu("Tools");
final JSlider slider1;
slider1 = new JSlider(JSlider.HORIZONTAL,0,4,1);
slider1.setToolTipText("Slide To Change Brightness");
slider1.setBorder(new SoftBevelBorder(BevelBorder.LOWERED, null, null, null, null));
slider1.setMajorTickSpacing(1);
slider1.setPaintLabels(true);
slider1.setPaintTicks(true);
slider1.setPaintTrack(true);
slider1.setAutoscrolls(true);
slider1.setBounds(50, 55, 200, 50);
slider1.addChangeListener(new ChangeListener()
{
@Override
public void stateChanged(ChangeEvent e)
{
System.out.println("Before");
fval=slider1.getValue();
chgBrt(fval);
repaint();
}
});
TitledBorder title;
title = BorderFactory.createTitledBorder("Operations");
title.setTitleJustification(TitledBorder.LEFT);
JButton RT90 = new JButton("");
JButton RT180 = new JButton("");
JButton RTM90 = new JButton("");
JButton RTM180 = new JButton("");
JButton NEXT = new JButton("");
Image img = null;
Image imgn = null;
try
{
img = ImageIO.read(getClass().getResource("/images/images_Horizontal.png"));
imgn = ImageIO.read(getClass().getResource("/images/next12.png"));
}
catch (IOException e)
{
e.printStackTrace();
}
RT90.setIcon(new ImageIcon(img));
RT180.setIcon(new ImageIcon(img));
RTM90.setIcon(new ImageIcon(img));
RTM180.setIcon(new ImageIcon(img));
NEXT.setIcon(new ImageIcon(imgn));
JPanel buttonPane = new JPanel();
buttonPane.add(slider1);
buttonPane.add(Box.createRigidArea(new Dimension(250,0)));
buttonPane.setBorder(title);
buttonPane.add(RT90);
buttonPane.add(RT180);
buttonPane.add(RTM90);
buttonPane.add(RTM180);
buttonPane.add(Box.createRigidArea(new Dimension(250,0)));
NEXT.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0)
{
nextImage();
}
});
buttonPane.add(NEXT);
getContentPane().add(buttonPane, BorderLayout.SOUTH);
final File dir = new File("");
final JFileChooser file;
file = new JFileChooser();
file.setCurrentDirectory(dir);
file.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
file.showOpenDialog(panel);
String path = file.getSelectedFile().getAbsolutePath();
System.out.println(path);
pictures= getFilesInFolder(path.toString());
Action nextpictureaction = new AbstractAction("Next Picture")
{
private static final long serialVersionUID = 2421742449531785343L;
@Override
public void actionPerformed(ActionEvent e)
{
nextImage();
}
};
setJMenuBar(menubar);
menubar.add(toolsmenu);
toolsmenu.add(nextpictureaction);
panel.add(label,BorderLayout.CENTER);
add(panel);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationByPlatform(true);
setSize(1000, 700);
setTitle("PictureEditor");
setVisible(true);
}
public Stack<File> getFilesInFolder(String startPath)
{
File startFolder = new File(startPath);
Stack<File> picturestack = new Stack<File>();
String extension;
int dotindex;
// Go through the folder
for (File file : startFolder.listFiles())
{
extension = "";
dotindex = file.getName().lastIndexOf('.'); // Get the index of the dot in the filename
if (dotindex > 0)
{
extension = file.getName().substring(dotindex + 1);
// Iterate all valid file types and check it
for (String filetype : validpicturetypes)
{
if (extension.equals(filetype))
{
picturestack.add(file);
}
}
}
}
return picturestack;
}
public void nextImage()
{
try
{
a=ImageIO.read(pictures.pop().getAbsoluteFile());
}
catch (IOException e1)
{
e1.printStackTrace();
}
final ImageIcon image = new ImageIcon(a);
label.setIcon(image);
repaint();
}
@SuppressWarnings("null")
public void chgBrt(float f)
{
Graphics g = null;
Graphics2D g2d=(Graphics2D)g;
try
{
BufferedImage dest=changeBrightness(a,(float)fval);
System.out.println("Change Bright");
int w = a.getWidth();
int h = a.getHeight();
g2d.drawImage(dest,w,h,this);
ImageIO.write(dest,"jpeg",new File("/images/dest.jpg"));
System.out.println("Image Write");
}
catch(Exception e)
{
e.printStackTrace();
}
}
public BufferedImage changeBrightness(BufferedImage src,float val)
{
RescaleOp brighterOp = new RescaleOp(val, 0, null);
return brighterOp.filter(src,null); //filtering
}
public static void main(String[] args)
{
javax.swing.SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new PictureEditor();
}
});
}
}
谁能指导我并告诉我我错在哪里？？