imagepreview.java

Java版拼图游戏

/*
 * @(#)ImagePreview.java 1.0 03/08/22
 * Copyright 2003 Entao Zhang, All rights reserved.
 */

import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import java.io.File;
import javax.swing.*;

/**
 * 图象预览
 */
public class ImagePreview implements PropertyChangeListener{
	private static JLabel labela=new JLabel();
	private static JLabel labelb=new JLabel();
	private ImagePreview(){};

	public static JPanel createPreview(final JFileChooser c){
		c.addPropertyChangeListener(JFileChooser.SELECTED_FILE_CHANGED_PROPERTY,
				new ImagePreview());

		labela.setIcon(null);
		labelb.setText(null);
		labela.setHorizontalAlignment(JLabel.CENTER);
		labelb.setHorizontalAlignment(JLabel.CENTER);
		labelb.setVerticalAlignment(JLabel.BOTTOM);
		labela.setBorder(BorderFactory.createEmptyBorder(0,10,0,0));
		labelb.setBorder(BorderFactory.createEmptyBorder(0,10,0,0));

		JPanel p=new JPanel();
		p.setLayout(new BorderLayout());
		p.add(labela,BorderLayout.CENTER);
		p.add(labelb,BorderLayout.SOUTH);
		p.setPreferredSize(new Dimension(120, 120));
		return p;
	}
	
	public void propertyChange(PropertyChangeEvent e) {
		File f=((File)e.getNewValue());
		if (f==null || f.isDirectory() 
					||!(f.getName().toLowerCase().endsWith(".jpg")||
						f.getName().toLowerCase().endsWith(".gif")  ) ) {
			labela.setIcon(null);
			labelb.setText(null);
		} else {
			ImageIcon tmp = new ImageIcon(f.getPath());
			labelb.setText("宽:"+tmp.getIconWidth()+" 高:"+tmp.getIconHeight());
			if (tmp.getIconWidth()>tmp.getIconHeight()){
				if(tmp.getIconWidth() > 115) {
					tmp=new ImageIcon(tmp.getImage().getScaledInstance
						(115, -1, Image.SCALE_DEFAULT));
				}
			}else{
				if(tmp.getIconHeight()>115){
					tmp=new ImageIcon(tmp.getImage().getScaledInstance
						(-1, 115, Image.SCALE_DEFAULT));
				}
			}
			labela.setIcon(tmp);
		}
	}
}