Java – “cannot find symbol method drawImage(java.awt.image.BufferedImage,,int,int)”

imagejavaswing

Okay, now I've been using drawImage in java for a while, and this has never happened before. Why can't it find "drawImage(java.awt.image.BufferedImage,<nulltype>,int,int)" in my code?

import java.awt.*;
import javax.swing.*;
import javax.swing.JPanel;
import java.awt.event.*;
import java.awt.image.*;     
import java.io.*;
import java.util.Arrays;
import javax.imageio.ImageIO;

public class imgtest extends JFrame{
    BufferedImage img;
    Graphics g2d;
    /**
     * Creates a new instance of imgtest.
     */
    public imgtest() {
        File file = new File("test.png");
        img = ImageIO.read(file);
    }

    /**
     * @param args the command line arguments
     */
    public void paint(Graphics g)
    {
        g2d = (Graphics2D)g;
        g2d.drawImage(img, null, 0, 0);
    }

    public static void main(String[] args) {
        imgtest i = new imgtest();
        i.setSize(640,480);
        i.setVisible(true);
        i.repaint();
        // TODO code application logic here
    }
}

Best Answer

You've declared g2d as a Graphics object, and Graphics doesn't have the drawImage(BufferedImage, BufferedImageOp, int, int) method. Fix: replace the line

Graphics g2d;

with

Graphics2D g2d;

When Java is looking for attributes of an object that's stored in a variable like this, it always uses the declared type of the variable, namely Graphics. The fact that you casted g to a Graphics2D doesn't make a difference unless you actually store it in a variable of type Graphics2D.

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