ClippedDragImage.java Source code

Introduction

Here is the source code for ClippedDragImage.java

Source

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;

import javax.swing.JComponent;
import javax.swing.JFrame;

public class ClippedDragImage extends DragImage {
    int oldX, oldY;

    public ClippedDragImage(Image i) {
        super(i);
    }

    public void mouseDragged(MouseEvent e) {
        imageX = e.getX();
        imageY = e.getY();
        Rectangle r = getAffectedArea(oldX, oldY, imageX, imageY, imageWidth, imageHeight);
        repaint(r); // repaint just the affected part of the component
        oldX = imageX;
        oldY = imageY;
    }

    private Rectangle getAffectedArea(int oldx, int oldy, int newx, int newy, int width, int height) {
        int x = Math.min(oldx, newx);
        int y = Math.min(oldy, newy);
        int w = (Math.max(oldx, newx) + width) - x;
        int h = (Math.max(oldy, newy) + height) - y;
        return new Rectangle(x, y, w, h);
    }

    public static void main(String[] args) {
        String imageFile = "A.jpg";
        Image image = Toolkit.getDefaultToolkit().getImage(ClippedDragImage.class.getResource(imageFile));
        image = image.getScaledInstance(imageWidth, imageHeight, Image.SCALE_DEFAULT);
        JFrame frame = new JFrame("ClippedDragImage");
        frame.getContentPane().add(new ClippedDragImage(image));
        frame.setSize(300, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

class DragImage extends JComponent implements MouseMotionListener {
    static int imageWidth = 60, imageHeight = 60;

    int grid = 10;

    int imageX, imageY;

    Image image;

    public DragImage(Image i) {
        image = i;
        addMouseMotionListener(this);
    }

    public void mouseDragged(MouseEvent e) {
        imageX = e.getX();
        imageY = e.getY();
        repaint();
    }

    public void mouseMoved(MouseEvent e) {
    }

    public void paint(Graphics g) {
        Graphics2D g2 = (Graphics2D) g;

        g2.drawImage(image, imageX, imageY, this);
    }

}