对于我的班级，我必须制作一个SlideShow JApplet。用户将能够打开他们选择的十张图片，并将在幻灯片放映中通过它们，每一张都有延迟。我把所有东西都放在我的代码中，他们能够调出打开的对话框来选择图像文件。但是一旦我开始搞乱我的buildPicturePanel（），当我运行文件时没有出现任何东西。有人可以给我一些帮助，我应该用这个改变或添加。请描述一下，这本书没有给出适用于此的图像的好例子。
到目前为止，这是我的代码。
public class Slideshow extends JApplet {
//setting all JItmes along with items for the image and timer
private JLabel display;
private JButton open ;
private JButton start ;
private JButton stop ;
private JPanel picturePanel;
private JPanel navigationPanel;
private JPanel mainPanel;
private BufferedImage pics;
private int counter = 0;
private ImageIcon[] pictures ;
private JLabel label;
int currentImage = -1;
String images[];
private Object image;
File selectedFile;
String fileName;
//basically the main method for a JApplet
public void init() {
this.setSize(400,500);
buildNavPanel();
buildPicturePanel();
mainPanel();
}
//creates the panel that will hold the slide show
private void buildPicturePanel(){
try{
pics = ImageIO.read(new File(fileName));
}catch(IOException ex){
System.out.println("Please open another selection of pictures.");
}
}
//navigation panel where user can hit add, start, stop
private void buildNavPanel(){
navigationPanel = new JPanel(new FlowLayout(FlowLayout.TRAILING));
navigationPanel.setLayout(new GridLayout(0,3));
open = new JButton("Open Images (Up to 10)");
start = new JButton ("Start Slide Show");
stop = new JButton ("Stop Slide Show");
open.addActionListener(new OpenListener());
navigationPanel.add(open);
navigationPanel.add(start);
navigationPanel.add(stop);
}
//main panel holds all panels with location
private void mainPanel(){
buildNavPanel();
buildPicturePanel();
add(navigationPanel,BorderLayout.SOUTH);
add(picturePanel, BorderLayout.CENTER);
}
//shows current picture
public void showCurrent(){
display.setIcon(new ImageIcon(images[currentImage]));
}
//shows next picture
public void showNext(){
currentImage = currentImage +1;
if (currentImage >= images.length){
currentImage = 0;
}
showCurrent();
}
//this will make the openlistener work
private class OpenListener implements ActionListener{
//actionevent for openlistener
public void actionPerformed(ActionEvent e) {
JFileChooser fc= new JFileChooser();
FileFilter filter = new FileNameExtensionFilter ("JPEG file", "jpg", "jpeg");
fc.setFileFilter(filter);
fc.setMultiSelectionEnabled(true);
int response = fc.showOpenDialog(null);
if (response == JFileChooser.APPROVE_OPTION){
selectedFile = fc.getSelectedFile();
fileName = selectedFile.getPath();
}
}
}
}
非常感谢任何帮助。