博客

使用awt图形化编程实现对于图片的打开与保存操作

首先是图形化界面：

菜单的操作中有两个选项：读取与保存

图片打开后可以显示在中间的画布上，保存选项可以保存在其他的地方

下面是保存在桌面上的效果

入口enter类:

package guidemo2;

public class Enter {

    public static void main(String[] args) {
        Demo demo = new Demo();
        demo.init();
    }

}

package guidemo2;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

public class Demo {
    private int width = 800;
    private int height = 700;

    Frame frame = new Frame();
    MenuBar menuBar = new MenuBar();
    Menu menu = new Menu("操作");
    MenuItem read = new MenuItem("读取");
    MenuItem save = new MenuItem("保存");

    BufferedImage bufferedImage;

    private class ShowImg extends Canvas {
        @Override
        public void paint(Graphics g) {
            g.drawImage(bufferedImage,0,0,null);
        }
    }

    public void init(){
        ShowImg img = new ShowImg();
        frame.setTitle("图片查看器");
        Toolkit tool = Toolkit.getDefaultToolkit();
        Dimension dimension = tool.getScreenSize();
        int scnWidth = dimension.width;
        int scnHeight = dimension.height;
        frame.setBounds((scnWidth-width)/2,(scnHeight-height)/2,width,height);

        read.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                FileDialog fileDialog = new FileDialog(frame,"打开文件",FileDialog.LOAD);
                fileDialog.setVisible(true);

                String directory = fileDialog.getDirectory();
                String file = fileDialog.getFile();
                try {
                    bufferedImage = ImageIO.read(new File(directory+file));
                    img.repaint();
                } catch (IOException e1) {
                    e1.printStackTrace();
                }

            }
        });

        save.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                FileDialog fileDialog = new FileDialog(frame,"保存文件",FileDialog.SAVE);
                fileDialog.setVisible(true);

                String directory = fileDialog.getDirectory();
                String file = fileDialog.getFile();
                try {
                    ImageIO.write(bufferedImage,"JPG",new File(directory,file));
                } catch (IOException e1) {
                    e1.printStackTrace();
                }
            }
        });

        menu.add(read);
        menu.add(save);
        menuBar.add(menu);
        frame.setMenuBar(menuBar);

        frame.add(img);
        img.setPreferredSize(new Dimension(800,700));

        frame.setVisible(true);
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }

}