(Java) How can I import and display sprites?

Question

I'm sorry if this is a noobish question, but I really need help with this. How can I import an image, and draw it on the screen? I suppose I need to use a BufferedImage, but how?

package com.jonas.game;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;

public class Game extends JFrame implements Runnable{

private static final long serialVersionUID = 1L;
int WIDTH = 1024;
int HEIGHT = 576;
int SCALE = 1;
int heroX,heroY;
int x,y;

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

public Game(){

    setSize(WIDTH * SCALE, HEIGHT * SCALE);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setLocationRelativeTo(null);
    setResizable(false);
    setTitle("BasicJava2DGame");
    setVisible(true);

    addKeyListener(new Input());

    heroX=getWidth()/2-16;
    heroY=getHeight()/2-16;

    try {
        while(true){
            update();
            Thread.sleep(20);
        }
    } catch (InterruptedException e) {
        e.printStackTrace();
    }

}

public void paint(Graphics g){

    Image offScreen = createImage(getWidth(),getHeight());
    draw(offScreen.getGraphics());

    g.drawImage(offScreen,0,0,null);
}

public void draw(Graphics g){

    g.setColor(Color.GRAY);
    g.fillRect(0,0,getWidth(),getHeight());

    g.setColor(Color.BLUE);
    g.fillOval(heroX, heroY, 32, 32);

    g.setColor(Color.WHITE);
    g.fillOval(heroX+6,heroY+8,8,8);
    g.fillOval(heroX+18,heroY+8,8,8);

    g.setColor(Color.BLACK);
    g.fillOval(heroX+8, heroY+10, 4, 4);
    g.fillOval(heroX+20, heroY+10, 4, 4);

    g.fillRect(heroX+6, heroY+22, 20, 2);


    repaint();

}

public void setX(int x){
    this.x=x;
}
public void setY(int y){
    this.y=y;
}
public void update(){
    heroX+=x;
    heroY+=y;
}

public class Input implements KeyListener{

    public void keyPressed(KeyEvent e) {
        int keyCode=e.getKeyCode();

        if(keyCode==KeyEvent.VK_W){
            setY(-5);
        }
        if(keyCode==KeyEvent.VK_A){
            setX(-5);
        }
        if(keyCode==KeyEvent.VK_S){
            setY(5);
        }
        if(keyCode==KeyEvent.VK_D){
            setX(5);
        }
        if(keyCode==KeyEvent.VK_ESCAPE){
            stop();
        }
    }

    public void keyReleased(KeyEvent e) {
        int keyCode=e.getKeyCode();

        if(keyCode==KeyEvent.VK_W){
            setY(0);
        }
        if(keyCode==KeyEvent.VK_A){
            setX(0);
        }
        if(keyCode==KeyEvent.VK_S){
            setY(0);
        }
        if(keyCode==KeyEvent.VK_D){
            setX(0);
        }
    }

    public void keyTyped(KeyEvent e) {

    }

}

public void run() {
    new Thread().start();
}
public void stop(){
    System.exit(0);
}

}

I guess this may help http://stackoverflow.com/questions/1626735/how-can-i-display-a-bufferedimage-in-a-jframe — kaysush, Feb 02 '13 at 11:49
What does createImage(getWidth(),getHeight()) do? Also, why do you draw the graphics twice? — G. Bach, Feb 02 '13 at 12:33
Do you mean paint and draw? One is doublebuffering, one is drawing game stuff. — sanoj00, Feb 02 '13 at 12:37
Yeah those are what I meant. Still not clear on what createImage(..) does. — G. Bach, Feb 02 '13 at 12:40

score 5 · Answer 1 · answered Feb 02 '13 at 11:50

5

To load you can use ImageIO.read:

BufferedImage image = ImageIO.read(new File(yourfilename));

In order to draw on a JPanel, get its Graphics and use drawImage method:

Graphics g = panel.getGraphics();
g.drawImage(image, x, y, imageObserver (most likely null));

answered Feb 02 '13 at 11:50

Daniel Cisek

931
3
9
23

Thanks for the help, but I can't seem to get it to work. I'm going to copy/paste the code I'm using for the game, and then you can help me implement it. – sanoj00 Feb 02 '13 at 12:16
`Graphics g = panel.getGraphics();` If you don't know why you should **not do custom painting that way,** search SO. It is discussed probably every 48 hours. – Andrew Thompson Feb 03 '13 at 02:33

score 0 · Answer 2 · answered Dec 10 '15 at 23:39

Here is the source for my file. I hope it works. I'm using NetBeans for this project:

package mygame;

import java.awt.*;
import java.io.File;
import javax.swing.*;

public class Main {

    private static void createAndShowGUI() {
        JFrame frame = new JFrame("Name");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JLabel emptyLabel = new JLabel();
        frame.add(new JLabel(new ImageIcon("Image path here")));
        emptyLabel.setPreferredSize(new Dimension(700, 400));
        frame.getContentPane().add(emptyLabel, BorderLayout.PAGE_START);
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
        @Override
        public void run() {
        createAndShowGUI();
    }
});
}
}

(Java) How can I import and display sprites?

2 Answers2