程序8-15：
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class JFileChooserDemo implements ActionListener {
JFrame frame = new JFrame ("JFileChooser Demo");
JFileChooser fc = new JFileChooser();
JTextField tf = new JTextField();
JButton openButton,saveButton,deleteButton;
public static void main(String args[]) {
JFileChooserDemo fcd = new JFileChooserDemo();
fcd.go();
}
public void go(){
ImageIcon openIcon = new ImageIcon("open.gif");
openButton = new JButton("Open a File...",openIcon);
openButton.addActionListener(this);
ImageIcon saveIcon = new ImageIcon("save.gif");
saveButton = new JButton("Save a File...",saveIcon);
saveButton.addActionListener(this);
ImageIcon deleteIcon = new ImageIcon("delete.gif");
deleteButton = new JButton("Delete a File...",deleteIcon);
deleteButton.addActionListener(this);
JPanel jp = new JPanel();
jp.add(openButton);
jp.add(saveButton);
jp.add(deleteButton);
Container cp = frame.getContentPane();
cp.add(jp,BorderLayout.CENTER);
cp.add(tf,BorderLayout.SOUTH);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(300,200);
frame.setVisible(true);
}
public void actionPerformed(ActionEvent e) {
JButton button = (JButton)e.getSource();
//“打开”文件对话框
if (button == openButton){
int select = fc.showOpenDialog(frame);
if (select == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
tf.setText("Opening," + file.getName() );
} else {
tf.setText("Open command cancelled by user" );
}
}
//“保存”文件对话框
if (button == saveButton){
int select = fc.showSaveDialog(frame);
if (select == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
tf.setText("Saving," + file.getName() );
} else {
tf.setText("Save command cancelled by user" );
}
}
//“删除”文件对话框
if (button == deleteButton){
int select = fc.showDialog(frame,"删除");
if (select == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
tf.setText("Deleting," + file.getName() );
}else {
tf.setText("Delete command cancelled by user" );
}
}
}
}