I've made a JFrame, and added a JPanel to it. I am trying to paint the window completely black, and it isn't working! Thank you in advance.
This is my Main class!
package com.lootdatdungeon.net;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
public class Main {
public static void main(String[] args){
initWindow();
}
public static void initWindow(){
Window window = new Window();
Thread windowThread = new Thread(window);
windowThread.start();
}
}
Okay, and here is my Window class!
package com.lootdatdungeon.net;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Window extends JFrame implements Runnable{
private static final long serialVersionUID = 1L;
private static final int HEIGHT = 240;
private static final int WIDTH = 320;
private static final int SCALE = 2;
private BufferedImage image;
private Graphics2D g;
private boolean running = true;
public Window(){
System.out.println("Window object made");
JFrame frame = new JFrame("Loot dat dungeon");
JPanel panel = new JPanel();
frame.setSize(WIDTH*SCALE,HEIGHT*SCALE);
frame.setVisible(true);
frame.setResizable(false);
frame.add(panel);
image = new BufferedImage(WIDTH,HEIGHT,BufferedImage.TYPE_INT_RGB);
g = (Graphics2D) image.getGraphics();
}
public void Draw(Graphics g){
System.out.println("Draw method ran");
g.setColor(Color.BLACK);
g.drawRect(0, 0, WIDTH, HEIGHT);
}
#Override
public void run() {
while(running){
Draw(g);
}
}
}
Simply do in this way using overriiden paintComponent() method of JPanel
JPanel panel = new JPanel() {
#Override
public void paintComponent(Graphics g) {
// don't forget to call it
super.paintComponent(g);
// set color
g.setColor(Color.BLACK);
// fill a rect that cover whole panel with specified color
g.fillRect(0, 0, getWidth(), getHeight());
}
};
Note: There is no need of Thread and BufferedImage in this case.
You should give this a read http://www.gametutorial.net/article/Java-game-framework
That site has a lot of good info if you want to create games. That's there I started.
Related
I created a chart extending JPanel and overriding paint() method. When I click on this panel I'd like to create a "snapshot" of the chart and open it in a new JFrame.
I tried by creating a buffered image as shown below, but the problem is that when I resize the window I loose lot of quality.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.image.BufferedImage;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class SnapshotDemo extends JPanel{
private JComponent src;
private BufferedImage img;
private final JFrame f = new JFrame();
public SnapshotDemo(JComponent src) {
super(new BorderLayout());
this.src = src;
this.img = takeSnapshot(src);
}
#Override
public void paint(Graphics g) {
Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.drawImage(img, 0, 0, getWidth(), getHeight(), null);
}
public void display(){
f.setContentPane(this);
f.setSize(1000,600);
f.setVisible(true);
}
public static BufferedImage takeSnapshot(JComponent src){
BufferedImage i = new BufferedImage(src.getWidth(), src.getHeight(), BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = i.createGraphics();
src.printAll(g2);
return i;
}
public static void main(String[] args) {
JPanel p = new JPanel(){
#Override
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2 = (Graphics2D)g.create();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
int x = 0;
int y = 0;
int stepx = getWidth()/5;
int stepy = getHeight()/5;
for(int i=0; i<10; i++){
g2.drawLine(x, y, x+stepx, y+stepy);
x+=stepx;
y+=stepy;
}
g2.setPaint(Color.red);
g2.drawOval(getWidth()/2-30, getHeight()/2-30, 60, 60);
}
};
p.addMouseListener(new MouseListener() {
#Override
public void mouseReleased(MouseEvent e) {}
#Override
public void mousePressed(MouseEvent e) {}
#Override
public void mouseExited(MouseEvent e) {}
#Override
public void mouseEntered(MouseEvent e) {}
#Override
public void mouseClicked(MouseEvent e) {
SnapshotDemo d = new SnapshotDemo(p);
d.display();
}
});
JFrame f = new JFrame();
f.setContentPane(p);
f.setSize(1000, 600);
f.setVisible(true);
}
}
Any idea about how to handle this issue better? Is there a way to avoid the use of images (BufferedImage etc...)?
Thanks in advance.
but the problem is that when I resize the window I loose lot of quality.
When you resize any image you lose quality. This is called pixilation. If you don't want to loose quality the don't resize the image larger.
I created a chart extending JPanel and overriding paint() method.
Don't override paint(). Custom painting is done by overriding paintComponent(...) and don't forget the super.paintComponent(...) at the start of the method.
But why are you even creating a custom panel. Just use the BufferedImage to create an ImageIcon and then add the ImageIcon to a JLabel. This way the image will always be displayed at its actual size so resizing the window will not affect the quality.
Hi I'm new to java GUI Programming. I created Jframe(MainFrame) and add JPanel(OutPanel) Which has another Jpanel(InnerPanel). I try to achieve drawing Image in InnerPanel, not drawing OutPanel. I want OutPanel used to be just Container. So as you see TestA. I get Graphics from InnerPanel in OutPanel's paintComponent() which is overided method.
So finally I can draw using InnerPanel's Graphics in OutPanel's paintComponent() method. but It couldn't work well. It couldn't draw Image one time when program starts. when I hided window and shown again, the program shows image. Even though that is part of Image, not all Image.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TestA{
private static Image image = GUI.loadImage("PlayerBoard.jpg");
public static void main(String[] args) {
TestA testA = new TestA();
}
public TestA() {
JFrame mainFrame = new JFrame("Main Frame");
mainFrame.setLayout(null);
mainFrame.setSize(500, 500);
mainFrame.setVisible(true);
mainFrame.setBackground(Color.black);
mainFrame.setLocation(800, 400);
OutPanel outPanel = new OutPanel();
mainFrame.getContentPane().add(outPanel);
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
outPanel.repaint();
}
private class OutPanel extends JPanel {
JPanel innerPanel;
public OutPanel() {
this.setLayout(null);
this.setLocation(0, 0);
this.setSize(500, 50);
this.setBackground(Color.red);
innerPanel = new JPanel();
this.innerPanel.setSize(400, 50);
this.innerPanel.setVisible(true);
this.add(innerPanel);
}
#Override
protected void paintComponent(Graphics g) {
// TODO Auto-generated method stub
super.paintComponent(g);
int width = 500;
int height = 50;
BufferedImage resized = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB_PRE);
Graphics gBuffer = resized.createGraphics();
gBuffer.drawImage(TestA.image, 0, 0, width, height, this);
Graphics gPanel = innerPanel.getGraphics();
gPanel.drawImage(resized, 0, 0, width, height, this);
}
}
}
So I try diffrerent way(TestB). Only different thing is I just moved drawImage() method and getGraphics() thing to InnerPanel's paintComponent() from OutPanel's paintComponent(). Here's another Code TestB. and It works well.
Why this happens. Is it relates to context?. What is Context. and could I draw InnerPanel's Image in OutPanel?
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TestB {
private static Image image = GUI.loadImage("PlayerBoard.jpg");
public static void main(String[] args) {
TestB testB = new TestB();
}
public TestB() {
JFrame mainFrame = new JFrame("Main Frame");
mainFrame.setLayout(null);
mainFrame.setSize(500, 500);
mainFrame.setVisible(true);
mainFrame.setBackground(Color.black);
mainFrame.setLocation(800, 400);
OutPanel outPanel = new OutPanel();
mainFrame.add(outPanel);
outPanel.repaint();
}
private class OutPanel extends JPanel {
JPanel innerPanel;
public OutPanel() {
this.setLayout(null);
this.setLocation(0, 0);
this.setSize(500, 50);
this.setBackground(Color.red);
innerPanel = new InnerPanel(this);
this.innerPanel.setSize(500, 50);
this.innerPanel.setVisible(true);
this.add(innerPanel);
this.repaint();
}
}
private class InnerPanel extends JPanel {
OutPanel outPanel;
public InnerPanel(OutPanel outPanel) {
this.outPanel = outPanel;
}
#Override
protected void paintComponent(Graphics g) {
// TODO Auto-generated method stub
super.paintComponent(g);
int width = 500;
int height = 50;
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.drawImage(TestB.image, 0, 0, width, height, this);
}
}
}
The paintComponent() method of a component is responsible for painting itself only. It should never know or care about any other component.
I want OutPanel used to be just Container.
Then do just that. Create the panel and set the layout manager for the outer panel and then add the outer panel to the JFrame.
Then create your inner panel and add it to the outer panel. Make sure you override the getPreferredSize() method of the inner panel so the layout manager of the outer panel can do its job.
Read the section from the Swing tutorial on Custom Painting for more information and working examples to start with.
I'm new to Java and I'm trying to display an image on JFrame.
I have the main class:
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class PingPong extends JPanel{
Ball ball = new Ball(this);
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
}
public static void main(String[] args){
/* Creating the frame */
JFrame frame = new JFrame();
frame.setTitle("Ping Pong!");
frame.setSize(600, 600);
frame.setBounds(0, 0, 600, 600);
frame.getContentPane().setBackground(Color.darkGray);
frame.add(new JLabel(new ImageIcon("images/Table.png")));
frame.setVisible(true);
}
}
and Ball class:
import java.awt.Graphics;
import java.awt.Image;
import javax.swing.ImageIcon;
import javax.swing.JPanel;
public class Ball {
int x,y;
ImageIcon ball = new ImageIcon("images/Ball.png");
Image ballImage = ball.getImage();
public Ball(JPanel panel){
this.x = panel.getWidth()/2;
this.y = panel.getHeight()/2;
}
public void repaint(Graphics g){
g.drawImage(ballImage, x, y, null);
}
}
I want to display the Ball image in the main.
How can I do it?
I saw something with repaint() and paintComponent.
I just want to draw the ball image on the frame.
Thanks in advance!
Fist you need to add your custom component PingPong to frame. Then custom paintComponent(Graphics g) will be called.
Secondly add drawing code to paintComponent(Graphics g).
public class PingPong extends JPanel {
private static final long serialVersionUID = 7048642004725023153L;
Ball ball = new Ball();
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
ball.paint(g);
}
public static void main(String[] args) {
/* Creating the frame */
JFrame frame = new JFrame();
frame.setTitle("Ping Pong!");
frame.setSize(600, 600);
frame.setBounds(0, 0, 600, 600);
frame.getContentPane().setBackground(Color.darkGray);
frame.add(new PingPong());
frame.setVisible(true);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
}
}
You have to use the ball class in your main method. There isn't an instantiated ball object inside any method, only an instance of the Ball class inside the Pong class.
You also never paint the method in the frame created in the main method.
In an attempt to make a very simple bullet-hell game to learn about java, I ran into a roadblock: repaint() wasn't calling paintComponent().
Here is the entire program, which for now simply draws an image I created 50 times per second onto a JPanel, which rests on a JFrame.
/*
* Bullet hell, by Nematodes
*/
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class bulletHell extends JFrame
{
private static final long serialVersionUID = 0L;
JPanel gamePanel = new JPanel();
int gameTimerDelay = 20;
int x, y = 0;
BufferedImage lightOrb;
javax.swing.Timer gameTimer;
public static void main(String[] args)
{
bulletHell createFrame = new bulletHell();
createFrame.frameConstructor();
}
public void frameConstructor()
{
// Construct frame and frame components
setTitle("Bullet hell");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
getContentPane().setLayout(new GridBagLayout());
setVisible(true);
GridBagConstraints gridConstraints;
gridConstraints = new GridBagConstraints();
gridConstraints.gridx = 0;
gridConstraints.gridy = 0;
gamePanel.setBackground(Color.BLACK);
gamePanel.setPreferredSize(new Dimension(700, 700));
getContentPane().add(gamePanel, gridConstraints);
pack();
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
setBounds((int) (0.5 * (screenSize.width - getWidth())),
(int) (0.5 * (screenSize.height - getHeight())), getWidth(), getHeight());
try
{
lightOrb = ImageIO.read(new File("C:/Users/Owner/Downloads/orb.bmp"));
}
catch(IOException e)
{
System.out.println("An issue occurred while trying to read orb.bmp");
}
// Start timer that draws game objects 50 times per second (50 FPS)
gameTimer = new javax.swing.Timer(gameTimerDelay, gameTimerAction);
gameTimer.setInitialDelay(0);
gameTimer.start();
}
ActionListener gameTimerAction = new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
repaint();
}
};
class GraphicsPanel extends JPanel
{
public GraphicsPanel()
{
}
// Draw all of the components
#Override
public void paintComponent(Graphics g)
{
Graphics2D g2D = (Graphics2D) g;
super.paintComponent(g2D);
g2D.drawImage(lightOrb, x, y, this);
g2D.dispose();
}
}
}
After some debugging with breakpoints and println methods, I can confirm that the correct image is being read, the timer in gameTimerAction is being called 50 times per second, and repaint() is not invoking paintComponent() at all.
I am somewhat new to Java programming, and might just be missing something simple.
Edit: Problem has been solved by changing gamePanel to a GraphicsPanel object. Unfortunately, this also means that my much larger pong project (which this project's flawed drawing logic was essentially copied from) only worked by a miracle, and might be unstable with certain code additions.
I can immediately see several problems:
Most Important: You never instantiate a GraphicsPanel object, nor do you add it to anything. The paintComponent(...) method will never be called on a JPanel that is neither rendered nor created. Why not make your gamePanel variable a GraphicsPanel object and not a JPanel object?
You never change x and y in your Timer, and so without change, no animation will occur.
Also you're calling dispose on a Graphics object given to you by the JVM, something you should never do. This breaks the Swing painting chain making the graphics of your GUI unstable.
So keep at it, you'll get there.
For example:
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.*;
public class BulletExample extends JPanel {
public static final String IMG_PATH = "http://www.i2clipart.com/cliparts/f/0/5/8/clipart-blue-circle-f058.png";
private static final int PREF_W = 700;
private static final int PREF_H = PREF_W;
private static final int TIMER_DELAY = 20;
private BufferedImage bullet;
private int bulletX;
private int bulletY;
public BulletExample() throws IOException {
URL imgUrl = new URL(IMG_PATH);
bullet = ImageIO.read(imgUrl);
new Timer(TIMER_DELAY, new BulletListener()).start();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (bullet != null) {
g.drawImage(bullet, bulletX, bulletY, this);
}
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private class BulletListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
bulletX++;
bulletY++;
repaint();
}
}
private static void createAndShowGui() throws IOException {
// create the drawing JPanel
BulletExample mainPanel = new BulletExample();
JFrame frame = new JFrame("BulletExample");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
// add it to the JFrame
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
try {
createAndShowGui();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
}
I am using JFrame and I have kept a background image on my frame. Now the problem is that the size of image is smaller then the size of the frame so i have to keep the same image once again on the empty part of the window. If user clicks maximize button than I may have to put the image on empty region of the frame at run time. Can anyone tell me how to accomplish this?
It sounds as though you are talking about tiling vs. stretching, though it's not clear which behaviour you want.
This program has examples of both:
import java.awt.BorderLayout;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.io.IOException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.AbstractAction;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main {
public static void main(String[] args) throws IOException {
final Image image = ImageIO.read(new URL("http://sstatic.net/so/img/logo.png"));
final JFrame frame = new JFrame();
frame.add(new ImagePanel(image));
frame.setSize(800, 600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
#SuppressWarnings("serial")
class ImagePanel extends JPanel {
private Image image;
private boolean tile;
ImagePanel(Image image) {
this.image = image;
this.tile = false;
final JCheckBox checkBox = new JCheckBox();
checkBox.setAction(new AbstractAction("Tile") {
public void actionPerformed(ActionEvent e) {
tile = checkBox.isSelected();
repaint();
}
});
add(checkBox, BorderLayout.SOUTH);
};
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
if (tile) {
int iw = image.getWidth(this);
int ih = image.getHeight(this);
if (iw > 0 && ih > 0) {
for (int x = 0; x < getWidth(); x += iw) {
for (int y = 0; y < getHeight(); y += ih) {
g.drawImage(image, x, y, iw, ih, this);
}
}
}
} else {
g.drawImage(image, 0, 0, getWidth(), getHeight(), this);
}
}
}
You want something like the background image of the windows desktop, when using the background image multiple times instead of resizing it or just display it centered?
You only have to keep the image once and just paint it multiple times in the paintComponent method.
Another way to tile an image is with TexturePaint:
public class TexturePanel extends JPanel {
private TexturePaint paint;
public TexturePanel(BufferedImage bi) {
super();
this.paint = new TexturePaint(bi, new Rectangle(0, 0, bi.getWidth(), bi.getHeight()));
}
#Override
protected void paintComponent(Graphics g) {
Graphics2D g2 = (Graphics2D) g;
g2.setPaint(paint);
g2.fill(new Rectangle(0, 0, getWidth(), getHeight()));
}
}