J2SE

[color=blue][/color]
package ioStream;

import java.awt.AWTEvent;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.AWTEventListener;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.MouseWheelEvent;
import java.awt.event.MouseWheelListener;
import java.awt.geom.AffineTransform;
import java.io.File;
import java.util.LinkedList;
import java.util.List;
import javax.swing.ImageIcon;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.filechooser.FileNameExtensionFilter;

/*
* 该代码意在实现照片查看器的功能
* 当按下“右箭头”时浏览下一张图片
* 当按下“左箭头"时浏览上一张图片
* 实现循环浏览
* 当按下"Ecs"时推出全屏浏览模式
* 当按下CTRL+“上箭头”时，全屏显示
* 只能浏览指定文件夹下面的所支持格式的图片（gif,jpg,png）
*链表的大小与他的最大角标相隔1
*/

public class PicsViewer {
static JFrame frame0;//原始的全屏显示的窗口
static int SWidth=Toolkit.getDefaultToolkit().getScreenSize().width;
static int SHeight=Toolkit.getDefaultToolkit().getScreenSize().height;
static Image icon=(new ImageIcon("PicsViewer/img.png")).getImage();//框架图标
JFileChooser chooser; //声明一个文件选择器对象
    static JPanel imgjp;
static Image img0=(new ImageIcon("image/cat.png")).getImage();//默认的一张图片
File files; 
     static int j=0;
     static int k=0;
     static File root;
     static  int i=0;  
     Timer T00;
     String[] Str;//获取文件名字符串
     static Image img;
    static  int xCoor,yCoor;//打印图片的左上角坐标
    static  int PWidth,PHeight;//图片的宽高(小于屏幕宽高的时候的)
    static int PWidth0,PHeight0;//图片宽高大于屏幕宽高的时候的图片宽高
    String CPath;//直接获得的路径
    String newPath;//经过转换后的路径
    static   List<Image> list=new LinkedList<Image>();
    int index=0;
    static  int index0=0;
    static double xCoor0=1,yCoor0=1;//图片在X轴缩放的倍数，图片在Y轴的缩放倍数；
    static boolean isFull=true;//是否全屏显示
   static  int now;//当前正在使用的图片
public PicsViewer(){
  frame0=new JFrame();
imgjp=new ImgsPanel();
imgjp.setBackground(new Color(51,51,51));
  frame0.add(imgjp);
  frame0.setTitle("PicsViewer1.0");
  frame0.setSize(SWidth,SHeight);
  frame0.setUndecorated(isFull);
  frame0.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  //不设置窗口的位置，是因为窗口默认的位置就是在桌面的左上角
  frame0.setIconImage(icon);//设置窗口图标
  frame0.setVisible(true);
/*
  * 程序一启动就弹出文件选择对话框让用户选择所要浏览的图片
  */
  try {
    UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");//设置为当前操作系统的外观
    JFileChooser chooser = new JFileChooser();
chooser.setDialogTitle("请选择要查看的图片");
chooser.addChoosableFileFilter(new FileNameExtensionFilter("常见图片格式", "jpg", "gif", "png"));
chooser.showOpenDialog(frame0);
int returnVal = chooser.showOpenDialog(frame0);
    if(returnVal == JFileChooser.APPROVE_OPTION) {    
    img=(new ImageIcon(chooser.getSelectedFile().toString())).getImage();    
    CPath=chooser.getCurrentDirectory().toString()+System.getProperty("file.separator");
    newPath=CPath.replaceAll("\\\\","/");//路径转换    
    root=new File(newPath);
    img0=img;    
    imgjp.repaint();
    findImage(root); 
   
    }
   

    } catch (Exception evt) {}  
Toolkit toolkit = Toolkit.getDefaultToolkit();
toolkit.addAWTEventListener(new ShortcutKeyListener(), AWTEvent.KEY_EVENT_MASK | AWTEvent.MOUSE_EVENT_MASK| AWTEvent.WINDOW_EVENT_MASK);
   
    /*添加键盘监听事件，当点击键盘上的方向键右键时浏览下一张图片，点击左箭头浏览上一张，当按下上箭头时对当前图片进行放大操作
     * 当按下下箭头时，对当前浏览的图片进行缩小操作
     * 同时添加鼠标滚轮监听事件，也对当前图片进行缩放操作
     *
     */
    imgjp.addMouseWheelListener(new MouseWheelListener(){
    public void mouseWheelMoved(MouseWheelEvent e){
    if(e.getWheelRotation()<0){//如果鼠标滚轮向上滚动，则放大图片
   
       }else{//否则缩小图片
     
           }
   
    }

    });



}


   
 


public void findImage(File dir){
File[] files=dir.listFiles();//得到当前路径下的所有文件和文件夹    
    for(int i=0; i<files.length; i++){    
    Str=new String[files.length];
    Str[i]=files[i].getAbsolutePath();//将路径和文件名存入字符串数组 
    //使用链表替代数组
    if(Str[i].endsWith(".jpg")||Str[i].endsWith(".gif")||Str[i].endsWith(".png")==true){
    list.add(index,(new ImageIcon(Str[i])).getImage());
      index++;
    } 
}   

}

//画图的算法有点问题？？？？
static class ImgsPanel extends JPanel{
private static final long serialVersionUID = 1L;
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D G2=(Graphics2D)g;
AffineTransform Trans=new AffineTransform();
PWidth=img0.getWidth(null);
PHeight=img0.getHeight(null);
if(PWidth<=SWidth&&PHeight<=SHeight){
xCoor=(SWidth-PWidth)/2;
yCoor=(SHeight-PHeight)/2;
PWidth0=PWidth;
PHeight0=PHeight;
Trans.scale(xCoor0,yCoor0);//对图片的缩放操作
// G2.setTransform(Trans);
}
     if(PWidth>SWidth||PHeight>SHeight){    
    yCoor0=SHeight/(PHeight*1.0);
    PHeight0=SHeight;
    PWidth0=(int)(PWidth*yCoor0);
    xCoor0=yCoor0;    
    xCoor=(SWidth-PWidth0)/2;
    yCoor=-(PHeight0-SHeight)/2;
    Trans.scale(xCoor0,yCoor0);//对图片的缩放操作
    // G2.setTransform(Trans);    
     }
     G2.drawImage(img0,xCoor,yCoor,PWidth0,PHeight0,this);


}
}   


static class Tim implements ActionListener{
public void actionPerformed(ActionEvent e){
//看来变量最好不要用相同的变量名
img0=(Image)(list.get(index0));
index0++;
if(index0==list.size()){
index0=0;
img0=(Image)(list.get(index0));
index0++;
imgjp.repaint();
   }
imgjp.repaint();
}
}

static class ShortcutKeyListener implements AWTEventListener {
public void eventDispatched(AWTEvent e) {
if (e.getClass() == KeyEvent.class) {

            // 被处理的事件是键盘事件.

            KeyEvent keyEvent = (KeyEvent) e;
            if (keyEvent.getID() == KeyEvent.KEY_PRESSED) {

                keyPressed(keyEvent);

            } else if (keyEvent.getID() == KeyEvent.KEY_RELEASED) {

                keyReleased(keyEvent);

            }

        }



    }
/*
  * 当只有一张图片是抛出异常，不能使用左右方向键，待解决
  */
private void keyPressed(KeyEvent e) {
switch(e.getKeyCode()){
     case KeyEvent.VK_RIGHT: if(list.size()!=1){
    img0=(Image)(list.get(index0));now=index0;index0++;
        if(index0==list.size()-1){
        index0=0;
        img0=(Image)(list.get(index0));
        now=index0;
index0++;
imgjp.repaint();
                                    }imgjp.repaint();
                                    }else{
                                    img0=(Image)(list.get(index0));
                                    imgjp.repaint();
                                    }break;
     case KeyEvent.VK_LEFT:
    if(list.size()!=1){
    if(index0>0){
    img0=(Image)(list.get(index0));now=index0;index0--;
                  imgjp.repaint();    
                                        }
                              if(index0<0){
                              index0=list.size()-1;
                              img0=(Image)(list.get(index0));now=index0;index0--;
                  imgjp.repaint();    
                                       }
                              }else{
                              index0=list.size()-1;
                              img0=(Image)(list.get(index0));now=index0;index0--;
                  imgjp.repaint();
                              }break;
     case KeyEvent.VK_ESCAPE:isFull=false;
     frame0=new JFrame();
imgjp=new ImgsPanel();
imgjp.setBackground(new Color(51,51,51));
  frame0.add(imgjp);
  frame0.setTitle("PicsViewer1.0");
  frame0.setSize(SWidth,SHeight);
  frame0.setUndecorated(isFull);
  frame0.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  frame0.setIconImage(icon);//设置窗口图标
  frame0.setVisible(true);
                                    break;    
                                
                            }
if ((e.isControlDown() == true)
&& (e.getKeyCode() == KeyEvent.VK_UP)) { isFull=true;
frame0=new JFrame();
imgjp=new ImgsPanel();
imgjp.setBackground(new Color(51,51,51));
  frame0.add(imgjp);
  frame0.setTitle("PicsViewer1.0");
  frame0.setSize(SWidth,SHeight);
  frame0.setUndecorated(isFull);
  frame0.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  frame0.setIconImage(icon);
  frame0.setVisible(true);

}
  


    }




    private void keyReleased(KeyEvent event) {
    }
  
   

}


public static void main(String[] args){
new PicsViewer();     

      }                                    

}