imageviewer.java

打开图片的浏览···给新手看下如何使用IO等功能···

package cx5_5;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;
public class ImageViewer
{
    public static void main(String[] args)
    {
        JFrame frame=new ImageViewerFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}
class ImageViewerFrame extends JFrame
{
        public ImageViewerFrame()
        {
                setTitle("ImageViewer");
                setSize(DEFAULT_WIDTH,DEFAULT_HEIGHT);
                setLocation(10,30);
                label=new JLabel();

     label.setHorizontalAlignment(JLabel.CENTER);
     label.setVerticalAlignment(JLabel.CENTER);
                add(label);
                chooser=new JFileChooser();
     chooser.setCurrentDirectory(null);
                //chooser.setCurrentDirectory(new File("."));
     //chooser.setCurrentDirectory(new File(".."));
     //chooser.setCurrentDirectory(new File("E:/java"));
                JMenuBar menuBar=new JMenuBar();
     menuBar.setBackground(Color.LIGHT_GRAY);
                setJMenuBar(menuBar);
                JMenu menu=new JMenu("文件(F)");
                menuBar.add(menu);
                JMenuItem openItem=new JMenuItem("打开(Open)");
                menu.add(openItem);
               openItem.addActionListener(new ActionListener(){
                        public void actionPerformed(ActionEvent event)
                        {
                                int result=chooser.showOpenDialog(null);
                                if(result==JFileChooser.APPROVE_OPTION)
                                {
                                    String name=chooser.getSelectedFile().getPath();
                                        label.setIcon(new ImageIcon(name));
                                }
                        }
                });
                JMenuItem exitItem=new JMenuItem("退出(Exit)");
                menu.add(exitItem);
                exitItem.addActionListener(new ActionListener(){
                        public void actionPerformed(ActionEvent event)
                        {
                                System.exit(0);
                        }
                });
        }
        private JLabel label;
        private JFileChooser chooser;
        private static final int DEFAULT_WIDTH=1000;
        private static final int DEFAULT_HEIGHT=700;
}