Frame练习-打开图片

import java.awt.EventQueue;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;

public class ImageViewer {
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable(){
            public void run(){
                JFrame frame=new ImageViewerFrame();
                frame.setTitle("Image");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setVisible(true);
            }
        });
    }
}
class ImageViewerFrame extends JFrame {
    private JLabel label;
    private JFileChooser chooser;
    private static final int DEFALUT_WIDTH=1000;
    private static final int DEFALUT_HEIGHT=1000;
    public ImageViewerFrame(){
        setSize(DEFALUT_WIDTH,DEFALUT_HEIGHT);
        label=new JLabel();
        add(label);
        chooser=new JFileChooser();
        chooser.setCurrentDirectory(new File("."));
        JMenuBar menuBar=new JMenuBar();
        setJMenuBar(menuBar);
        JMenu menu=new     JMenu("File");
        menuBar.add(menu);
        JMenuItem openItem=new JMenuItem("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("Exit");
        menu.add(exitItem);
        exitItem.addActionListener(new ActionListener(){

            public void actionPerformed(ActionEvent event) {
                System.exit(0);
            }

        });

    }
}