I have made a Java program (JFrame based) using Netbeans,
I would like to know if it is possible to print the layout of the program
I wish to have a button and set the function to "print"
and the final layout of the frame will be printed, is it possible?
If yes, any reference source?
This will depend on what it is you hope to achieve.
You could simply print the contents of the frame to a BufferedImage. This allows you to control what you want to capture, in that you could print the content pane instead of the frame.
You could use Robot to capture the screen. This will capture what ever is on the screen at the location you are trying to capture, which might include more then just your frame...
"Print" vs "Capture"
import java.awt.EventQueue;
import java.awt.Graphics2D;
import java.awt.GridBagLayout;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.AbstractAction;
import javax.swing.ActionMap;
import javax.swing.InputMap;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.KeyStroke;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class PrintFrame {
public static void main(String[] args) {
new PrintFrame();
}
public PrintFrame() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JLabel label = new JLabel("Clap if you're happy");
final JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new GridBagLayout());
frame.add(label);
frame.setSize(200, 200);
frame.setLocationRelativeTo(null);
InputMap im = label.getInputMap(JLabel.WHEN_IN_FOCUSED_WINDOW);
ActionMap am = label.getActionMap();
im.put(KeyStroke.getKeyStroke(KeyEvent.VK_P, KeyEvent.CTRL_DOWN_MASK), "Print");
im.put(KeyStroke.getKeyStroke(KeyEvent.VK_P, KeyEvent.CTRL_DOWN_MASK | KeyEvent.ALT_DOWN_MASK), "PrintAll");
am.put("Print", new AbstractAction() {
#Override
public void actionPerformed(ActionEvent e) {
try {
System.out.println("Print...");
BufferedImage img = new BufferedImage(frame.getWidth(), frame.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = img.createGraphics();
frame.printAll(g2d);
g2d.dispose();
ImageIO.write(img, "png", new File("Print.png"));
} catch (IOException ex) {
ex.printStackTrace();
}
}
});
am.put("PrintAll", new AbstractAction() {
#Override
public void actionPerformed(ActionEvent e) {
try {
System.out.println("PrintAll...");
Robot bot = new Robot();
Rectangle bounds = frame.getBounds();
bounds.x -= 2;
bounds.y -= 2;
bounds.width += 4;
bounds.height += 4;
BufferedImage img = bot.createScreenCapture(bounds);
ImageIO.write(img, "png", new File("PrintAll.png"));
} catch (Exception ex) {
ex.printStackTrace();
}
}
});
frame.setVisible(true);
}
});
}
}
Updated with better requirements
The basic requirement doesn't change a lot. You still need to capture the screen some how...
Here I've modified by "print" code to send the resulting BufferedImage to the printer. Note, I've done no checking to see if the image will actually fit, I'm sure you can work that out ;)
am.put("Print", new AbstractAction() {
#Override
public void actionPerformed(ActionEvent e) {
try {
System.out.println("Print...");
BufferedImage img = new BufferedImage(frame.getWidth(), frame.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = img.createGraphics();
frame.printAll(g2d);
g2d.dispose();
PrinterJob pj = PrinterJob.getPrinterJob();
pj.setPrintable(new FramePrintable(img));
if (pj.printDialog()) {
pj.print();
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
});
Then, you simply need some way to actually render the contents to the printer...
public class FramePrintable implements Printable {
private BufferedImage img;
public FramePrintable(BufferedImage img) {
this.img = img;
}
#Override
public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
if (pageIndex == 0) {
Graphics2D g2d = (Graphics2D) graphics;
g2d.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
double x = (pageFormat.getImageableWidth() - img.getWidth()) / 2;
double y = (pageFormat.getImageableHeight()- img.getHeight()) / 2;
g2d.drawImage(img, (int)x, (int)y, null);
}
return pageIndex == 0 ? PAGE_EXISTS : NO_SUCH_PAGE;
}
}
This is pretty much take straight from the Printing trial...
The simplest way is to use class Robot that can capture screen fragment at given coordinates. Take a look on this discussion: Java print screen program
Just send to robot the absolute coordinates of your JFrame
Try taking a screenshot and save it to a file. Then you can print the file. The following code snippet can be used to take a screenshot :
boolean captureScreenShot()
{
boolean isSuccesful = false;
Rectangle screenRect = new Rectangle(0,0,500,500);//frame absolute coordinates
BufferedImage capture;
try {
capture = new Robot().createScreenCapture(screenRect);
// screen shot image will be save at given path with name "screen.jpeg"
ImageIO.write(capture, "jpg", new File( "c:\\abc", "screen.jpeg"));
isSuccesful = true;
} catch (AWTException awte) {
awte.printStackTrace();
isSuccesful = false;
}
catch (IOException ioe) {
ioe.printStackTrace();
isSuccesful = false;
}
return isSuccesful;
}
Related
I am making a 2d game and I need to draw an image on top of another. After I draw the first image(the larger one, jpg), the second image(the smaller one,png) erases from where the second image is to the lower right hand corner. Like this:
I have looked into this a bit, and it was suggested that I use buffered images, so I did that with both images and the problem remains. Here is one post I looked at: How to draw an image over another image?. I have also seen some people suggesting graphics2d, though I did not really understand the reason to use them or how to use them. I am new to java graphics and images, so it is probably a silly mistake.
Here is my code. Thank you.
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import javax.swing.*;
import java.util.ArrayList;
import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.io.IOException;
public class DisplayExample extends JComponent
{
private BufferedImage backgroundImage;
private String backgroundName;
private BufferedImage image; //image to draw
private int imageX; //position of left edge of image
private int imageY; //position of top edge of image
private JFrame frame;
public static void main(String[] args)
{
DisplayExample example = new DisplayExample();
example.run();
}
public DisplayExample()
{
imageX = 200;
imageY = 200;
backgroundName = "backgroundShip.jpg";
URL backgroundURL = getClass().getResource(backgroundName);
if (backgroundURL == null)
throw new RuntimeException("Unable to load: " + backgroundName);
try{backgroundImage = ImageIO.read(backgroundURL);}catch(IOException ioe){}
//load image
String fileName = "explosion.png";
URL url = getClass().getResource(fileName);
if (url == null)
throw new RuntimeException("Unable to load: " + fileName);
//image = new ImageIcon(url).getImage();
try{image = ImageIO.read(url);}catch(IOException ioe){}
System.out.println(image instanceof BufferedImage);
setPreferredSize(new Dimension(1040,500)); //set size of drawing region
//need for keyboard input
setFocusable(true); //indicates that WorldDisp can process key presses
frame = new JFrame();
frame.getContentPane().add(this);
frame.pack();
frame.setVisible(true);
}
public void paintComponent(Graphics g)
{
super.paintComponent(g);
if(backgroundImage != null)
g.drawImage(backgroundImage,0,0,getWidth(), getHeight(), null);
g.drawImage(image, imageX, imageY, this);
}
public void run()
{
while(true)
{
imageY+=1;
repaint();
try{Thread.sleep(100);}catch(Exception e){}
}
}
}
So I took your code, added my own images and it runs fine for me.
Having said that, there are some areas you can improve:
You're running the risk of either blocking the Event Dispatching Thread or introducing a thread race condition into your code with your run method. You should consider using a Swing Timer instead. See How to use Swing Timers for more details. This allows you to schedule regular callbacks which are called within the context of the EDT, making it safer to update the context of the UI
You should only ever create or modify the state of the UI from within the context of the EDT, Swing is not thread safe. See Initial Threads for more details. Swing has been known to have "issues" when the UI is not initialised within the EDT
Scaling an image is expensive, you should avoid doing so from within the paint methods, instead, scale the image and keep a reference to the result and use it when you need to paint it.
You should consider using the key bindings API over KeyListener, it will solve many of the issues associated with using KeyListener. See How to Use Key Bindings for more details.
For example...
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
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.JComponent;
import javax.swing.JFrame;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class DisplayExample extends JComponent {
private BufferedImage backgroundImage;
private String backgroundName;
private BufferedImage image; //image to draw
private int imageX; //position of left edge of image
private int imageY; //position of top edge of image
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
DisplayExample example = new DisplayExample();
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(example);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public DisplayExample() {
imageX = 200;
imageY = 200;
try {
backgroundImage = ImageIO.read(new File("..."));
} catch (IOException ioe) {
ioe.printStackTrace();
}
//load image
try {
image = ImageIO.read(new File("..."));
} catch (IOException ioe) {
ioe.printStackTrace();
}
//need for keyboard input
//setFocusable(true); //indicates that WorldDisp can process key presses
// Use the key bindings API instead, causes less issues
Timer timer = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
imageY += 1;
repaint();
}
});
timer.start();
}
#Override
public Dimension getPreferredSize() {
return backgroundImage == null ? new Dimension(200, 200) : new Dimension(backgroundImage.getWidth(), backgroundImage.getHeight());
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
if (backgroundImage != null) {
// Scaling is expensive, don't do it here
int x = (getWidth() - backgroundImage.getWidth()) / 2;
int y = (getHeight() - backgroundImage.getHeight()) / 2;
g2d.drawImage(backgroundImage, x, y, this);
}
g2d.drawImage(image, imageX, imageY, this);
g2d.dispose();
}
}
I have a for loop that iterates within an actionPerformed method. Basically, I have a car game. I have a panel where car images travel from side to side in a JPanel. I am trying to have the cars stop at the finish line (I am doing that by sleeping when the image reaches a certain x value) display the race results, leave the screen and race again. I need to do that four times until we have a winner.
private class RaceDisplay extends JPanel implements ActionListener{
private Image img1,img2;
private int velX1,velX2;
private int x1,x2;
private Timer tm;
private JTextArea text1 = new JTextArea();
public RaceDisplay(){
tm = new Timer(30,this);
x1=0;
x2=0;
velX1=2;
velX2 =2;
}
public void paintComponent(Graphics g){
super.paintComponent(g);
ImageIcon car1 = new ImageIcon("...");
ImageIcon car2 = new ImageIcon("...");
img1 = car1.getImage();
img2 = car2.getImage();
g.drawImage(img1,x1,100,null);
g.drawImage(img2,x2,200,null);
tm.start();
}
public void actionPerformed(ActionEvent e) {
x1=x1+velX1;
velX2= x2+velX2;
repaint();
for(int count = 0;count<=4;count++){//<-----loop with issues.
if(count == 1){
text1.setText(result());
}
if(x1>=650 && x2>=650){ //does this when both cars reach the line
velX1=0;
velX2=0;
try {
Thread.sleep(2500);
} catch (InterruptedException ex) {
Logger.getLogger(Display.class.getName()).log(Level.SEVERE, null, ex);
}
x1=0;
x2=0;
repaint();
velX1= x1+velX1;
velX2= x2+velX2;
}
}
repaint();
}
I created the for loop that should check the if statements when it reaches the last counter it displays the winner(method for winner in the code). I was expecting the images to travel from side to four times and display the results four times.
But it only display anything if i set the if(counter==1) to (counter==0).
Can anyone help?
Thanks.
Don't call tm.start(); from within the paintComponent method, this is just asking for trouble. Painting may occur for any number of reasons, many of which you don't control or have knowledge about
Don't call Thread.sleep from within the context of the Event Dispatching Thread. This isn't stopping the Timer, but is prevent the EDT from processing the Event Queue, which includes things like repaint events and timer events...
Instead, once you've detected that a car has passed the finish line, you can either, stop updating that car's position and/or stop the Timer
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private Map<BufferedImage, Rectangle> carBounds;
private BufferedImage blueCar;
private BufferedImage redCar;
public TestPane() {
carBounds = new HashMap<>(25);
try {
blueCar = ImageIO.read(getClass().getResource("/BlueCar.png"));
redCar = ImageIO.read(getClass().getResource("/RedCar.png"));
int x = 0;
int y = (200 / 2 ) - blueCar.getHeight();
carBounds.put(blueCar, new Rectangle(x, y, blueCar.getWidth(), blueCar.getHeight()));
y = (200 / 2);
carBounds.put(redCar, new Rectangle(x, y, redCar.getWidth(), redCar.getHeight()));
} catch (IOException ex) {
ex.printStackTrace();
}
Timer timer = new Timer(40, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
for (BufferedImage img : carBounds.keySet()) {
Rectangle bounds = carBounds.get(img);
int xDelta = (int)Math.round((Math.random() * 7) + 1);
bounds.x += xDelta;
if (bounds.x + bounds.width > getWidth()) {
bounds.x = getWidth() - bounds.width;
((Timer)e.getSource()).stop();
}
}
repaint();
}
});
timer.start();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
for (BufferedImage img : carBounds.keySet()) {
Rectangle bounds = carBounds.get(img);
g2d.drawImage(img, bounds.x, bounds.y, this);
}
g2d.dispose();
}
}
}
Take a closer look at Concurrency in Swing for more details
class DrawIma extends JPanel{
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (int i=0;i<20;i++){
for (int j=0;j<20;j++) {
g.drawImage(BuArr[i*20+j], 20*i, 20*j, 20, 20, null);
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
In this part, BuArr are the 400 blocks divided from a BufferedImage, now i want them to be draw one by one, but the method can not draw the blocks separately, how can i do this?
Swing is single thread and not thread safe.
This means that you should not perform any long running or blocking (Thread.sleep) operations within the IU thread (the Event Dispatching Thread). It also means that you can not update, modify or create UI elements outside of the EDT context.
Instead, use a Swing Timer to generate a repeated callback at a specified interval and render the portions of the image to something like a BufferedImage, which you can the paint to the component via its paintComponent method...
See Concurrency in Swing and How to use Swing Timers for more details
Because it was a good time waster
This generates a List of Rectangles which represent the individual blocks I want to paint, I then randomise the List and run the Timer, picking the top most Rectangle off the List and using BufferedImage#getSubImage to draw it from the master to the buffer, which gets painted to the screen...
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestImage {
public static void main(String[] args) {
new TestImage();
}
public TestImage() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private BufferedImage master;
private BufferedImage copy;
private List<Rectangle> blocks;
public TestPane() {
setBackground(Color.BLACK);
try {
master = ImageIO.read(new File("..."));
copy = new BufferedImage(master.getWidth(), master.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = copy.createGraphics();
AlphaComposite composite = AlphaComposite.getInstance(AlphaComposite.CLEAR, 0.0f);
g2d.setComposite(composite);
g2d.setColor(new Color(0, 0, 0, 0));
g2d.fillRect(0, 0, master.getWidth(), master.getHeight());
g2d.dispose();
int blockSize = 40;
int width = master.getWidth();
int height = master.getHeight();
float aspect = Math.min(width, height) / (float) Math.max(width, height);
int blockHeight = blockSize;
blocks = new ArrayList<>(blockSize * 2);
for (int y = 0; y < master.getHeight(); y += blockHeight) {
if (y + blockHeight > master.getHeight()) {
blockHeight = master.getHeight() - y;
}
int blockWidth = blockSize;
for (int x = 0; x < master.getWidth(); x += blockWidth) {
if (x + blockWidth > master.getWidth()) {
blockWidth = master.getWidth() - x;
}
Rectangle block = new Rectangle(x, y, blockWidth, blockHeight);
blocks.add(block);
}
}
Collections.shuffle(blocks);
Timer timer = new Timer(40, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (blocks.isEmpty()) {
((Timer) e.getSource()).stop();
} else {
Graphics2D g2d = copy.createGraphics();
Rectangle block = blocks.remove(0);
g2d.drawImage(master.getSubimage(block.x, block.y, block.width, block.height), block.x, block.y, TestPane.this);
g2d.dispose();
repaint();
}
}
});
timer.start();
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
public Dimension getPreferredSize() {
return master == null ? new Dimension(200, 200) : new Dimension(master.getWidth(), master.getHeight());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
if (copy != null) {
int x = (getWidth() - copy.getWidth()) / 2;
int y = (getHeight() - copy.getHeight()) / 2;
g2d.drawImage(copy, x, y, this);
}
g2d.dispose();
}
}
}
I have a pretty big image that I want to display on my JFrame and applet, the JFrame/Applet is 765x503 in size but the image is way larger. I need a way to display the image in real size. How can I make it so I can move the screen around to display some of the image and be able to move around the image?
I want to be able to drag the screen around, not use Scrollbars.
JScrollPane might be the one you need.. add both vertical and horizontal scrolls
The basic idea is you need to provide some kind of offset that should be applied to the image to be drawn.
When the user presses the mouse button at a point on the image, you record the click point. When the drag the mouse, you delta the difference. This gives you the amount the offset is to be moved. Based on the original position, you simply add this difference to the and generate a new offset.
There are other ways to do it, but generally, this is the method I use.
I've also added code to check to see if the drag would put the image out of bounds of the viewable area, you'll have to decide if you want to use it...
import java.awt.Cursor;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
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;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class BigImage {
public static void main(String[] args) {
new BigImage();
}
public BigImage() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private BufferedImage bg;
private Point offset = new Point(0, 0);
public TestPane() {
try {
bg = ImageIO.read(new File("/path/to/image"));
} catch (IOException ex) {
ex.printStackTrace();
}
MouseAdapter ma = new MouseAdapter() {
private Point clickPoint;
private Point origin;
#Override
public void mousePressed(MouseEvent e) {
setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
clickPoint = e.getPoint();
origin = new Point(offset);
}
#Override
public void mouseReleased(MouseEvent e) {
setCursor(Cursor.getDefaultCursor());
clickPoint = null;
}
#Override
public void mouseDragged(MouseEvent e) {
int x = e.getPoint().x - clickPoint.x;
int y = e.getPoint().y - clickPoint.y;
offset.x = origin.x + x;
offset.y = origin.y + y;
if (offset.x > 0) {
offset.x = 0;
}
if (offset.x + bg.getWidth() < getWidth()) {
offset.x = -bg.getWidth() + getWidth();
}
if (offset.y > 0) {
offset.y = 0;
}
if (offset.y + bg.getHeight() < getHeight()) {
offset.y = -bg.getHeight() + getHeight();
}
repaint();
}
};
addMouseListener(ma);
addMouseMotionListener(ma);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(800, 600);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (bg != null) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.drawImage(bg, offset.x, offset.y, this);
g2d.dispose();
}
}
}
}
I have the following code.I want to display the images in my chick array on the screen after some time delay.The coordinates have to be shifted by 10px each x direction when the new
image is loaded.I would like to know what additional code snippets can i add in this code to have an animation on my Frame with the two images i have .Below is my code:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
public class Chicken extends Frame implements Runnable{
Thread animation;
long frameDelay = 3000;
Image chick[] = new Image[2];
int numFrames = chick.length;
Toolkit tk = getToolkit();
public Chicken()
{
setSize(new Dimension(300,300));
setVisible(true);
setBackground(Color.BLACK);
animation = new Thread(this);
chick[0] = tk.createImage("stand.png");
chick[1] = tk.createImage("walk.png");
animation.start();
//setVisible(false);
}
public void paint(Graphics g)
{
g.drawImage(chick[0],100,100,null );
}
#Override
public void run() {
// TODO Auto-generated method stub
repaint();
try {
Thread.sleep(frameDelay);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void main(String args[])
{
Chicken instance = new Chicken();
}
}
So, the first problem you have is a resource issue.
Resources stored "within" the application (typically known as embedded resources) can't be loaded like external resources.
chick[0] = tk.createImage("stand.png");
Is expecting a file "./stand.png" which doesn't exist. Instead, you need to load the resource through the Class#getResource API...
chick[0] = tk.createImage(getClass().getResource("/stand.png"));
The second problem you will face is the fact that you are overriding paint of a top level container. This really shouldn't be done. Let's start with the fact it's not double buffered and end with the fact that frames have decorations which sit inside the viewable area. This means that the decorations will overlap what ever you paint to the surface...not pretty...
The third problem is you are not telling the image where it should move to. It's static.
You need some kind of x/y value that tells the image where it should be painted. You would modify these values by a given x/y delta within you thread before you called repaint...
The forth problem you might have is the fact that you are using AWT...which is kind of dated. Swing would solve your double buffering issue for you...IMHO, would make a better choice - there's a lot more documentation and examples on Swing laying around now days ;)
While I'm on my hobble horse...I would, personally, recommend ImageIO over Toolkit#createImage or ImageIcon, mostly because it supports more formats, but also because it will throw an Exception when the image can't be read for some reason...
I have a simple example if Swing, but I won't post it, because I'll get in trouble for running of topic...let me know if you would like to see it
Updated with Swing example
This uses a embedded image in the default package...
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class ChickenDance {
public static void main(String[] args) {
new ChickenDance();
}
public ChickenDance() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private BufferedImage chicken;
private int xPos;
private int yPos;
private int xDelta = 4;
public TestPane() {
try {
chicken = ImageIO.read(getClass().getResource("/Chicken.png"));
} catch (IOException ex) {
Logger.getLogger(ChickenDance.class.getName()).log(Level.SEVERE, null, ex);
}
Timer timer = new Timer(40, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
xPos += xDelta;
if (xPos + chicken.getWidth() > getWidth()) {
xPos = getWidth() - chicken.getWidth();
xDelta *= -1;
} else if (xPos < 0) {
xPos = 0;
xDelta *= -1;
}
yPos = (getHeight() - chicken.getHeight()) / 2;
repaint();
}
});
if (chicken != null) {
timer.start();
}
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (chicken != null) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.drawImage(chicken, xPos, yPos, this);
g2d.dispose();
}
}
}
}