java 图像显示

简介

java 核心编程

code

/*
 * @Author: your name
 * @Date: 2020-10-28 22:38:26
 * @LastEditTime: 2020-10-28 22:45:52
 * @LastEditors: Please set LastEditors
 * @Description: In User Settings Edit
 * @FilePath: /java/ImageTest.java
 */
import java.awt.*;

import javax.swing.*;

public class ImageTest {
    public static void main(String[] args){
        EventQueue.invokeLater(()->{
            JFrame frame = new ImageFrame();
            frame.setTitle("ImageTest");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setVisible(true);
        });;
    }
}

class ImageFrame extends JFrame {
    public ImageFrame() {
        add(new ImageComponent());
        pack();
    }
}

class ImageComponent extends JComponent {
    private static final int DEFAULT_WIDTH = 300;
    private static final int DEFAULT_HEIGHT = 200;

    private Image image;

    public ImageComponent(){
        image = new ImageIcon("test.gif").getImage();
    }

    public void paintComponent(Graphics g) {
        if (image == null)
            return;

        int imageWidth = image.getWidth(this);
        int imageHeight = image.getHeight(this);

        // draw the iamge in the upper-left cornet

        g.drawImage(image, 0, 0, null);

        // tile the iamge across the component

        for (int i = 0; i * imageWidth <= getWidth(); i++) {
            for (int j = 0; j * imageHeight <= getHeight(); j++) {
                if (i + j > 0) {
                    g.copyArea(0, 0, imageWidth, imageHeight, i * imageWidth, j * imageHeight);
                }
            }
        }
    }

    public Dimension getPreferredSize() {
        return new Dimension(DEFAULT_WIDTH, DEFAULT_HEIGHT);
    }
}

image