Drawing Images in awt Panel object

HI,
I need to display an image in a Label.
My project is using awt and not swing. Can anyone help he how to use an setIcon() equivalent in an awt label.
I have tried to work around a bit and remove the label from the parent container and diaplay an image. but that doesn't seem to be working. Any help in this regard would be greatly appreciated.
if( form.equalsIgnoreCase("G")){
Container c = label.getParent();
label.setVisible( false );
Graphics g = c.getGraphics();
Image image = Toolkit.getDefaultToolkit().getImage("abc.gif");
g.drawImage( image, 10, 10, c );
g.dispose();
Thanks

Hi Subham! Here's an excerpt from the docs for java.awt.Label.
"A Label object is a component for placing text in a container. A label displays a single line of read-only text. The text can be changed by the application, but a user cannot edit it directly."
Ergo, you cannot use an image in lieu of text for a Label object. What you can do, though, is to write your own label class, subclassing from java.awt.Component, exactly as the java.awt.Label does and add the capability of using an image rather than just text.
Hope this helps!
Cheers!

Similar Messages

Drawing Graphics in AWT panel

I was wondering if anybody knows how I would go about drawing onto a Panel as a result of an actionPerformed() call. I got the original code for displaying an image onto the Panel from aresICO on this forum and now I need to be able to click a button on the GUI and have something drawn onto that Panel.
import java.applet.*;
import java.awt.*;
import java.awt.image.ImageObserver;
public class iPane extends Panel {
     Image im;
     boolean loaded = false;
     public iPane () {
          Toolkit tk = Toolkit.getDefaultToolkit ();
          im = tk.getImage ("Map of Dublin.jpg");
          prepareImage (im, -1, -1, this);
     public void paint (Graphics g) {
          if (loaded)
          g.drawImage (im, 20, 20, this);
     public void update (Graphics g) {
          paint (g);
          // if proper values loaded then:
          //drawRoute (g);
     public void drawRoute (Graphics g) {
          g.setColor(Color.red);
          g.drawLine(273,51,334,61);
          // method takes in values from a file etc.
     public synchronized boolean imageUpdate (Image image, int infoFlags,int x, int y, int width, int height) {
          if ((infoFlags & ImageObserver.ALLBITS) != 0) {
               loaded = true;
               repaint();
               return false;
          else {
               return true;
     public Dimension getPreferredSize() {
          return new Dimension(im.getWidth(this),im.getHeight(this));
     public Dimension getMinimumSize() {
          return getPreferredSize();
}; // end iPane class
This is a the relevant part of the class which uses an iPane object:
iPane mapPanel;
public void actionPerformed(ActionEvent e)
     String buttonLabel = e.getActionCommand();
     if (e.getSource() instanceof Button)
          if (buttonLabel.equals("Get Directions"))
// What goes in here to draw a line for example?
// How do I call a method from iPane to draw something?
Thanks.

Davey,
I don't think your approach is correct. The golden rule of Java graphics is that ALL of painting on a component should be done within the componen'ts paint method(). If you write to iPane from outside the class, then if your iPanel needs to be repainted (because, for example, it got obscured by another window and then unobscured) then the route would not be shown.
You have to think OOD on this.
The route and the image are properties of the of iPanel. The button push requests a change of those properties and display of the results on the screen.
This is what I would do:
1. Create member variables in the class iPanel that define the route.
2. Have a method which sets those variables. This method should call repaint after setting the variables.
2. Maybe have another boolean which says whether the routine is to be displayed or not. This method should call repaint after setting the boolean.
3. Change the paint method to draw the route, if required.
4. In the class that uses iPanel, simply call the methods in iPanel that set the route properties.
5. Change your class name to IPanel. All class names should start with an upper case letter.
e.g.,
private Point start;
private Point end;
private boolean displayRoute
public setRoute(Point newStart, Point newEnd) {
start = newStart;
end = newEnd;
repaint(); // maybe only call if new value is different
public void setDisplayRoute(boolean value) {
displayRoute = value;
repaint(); // maybe only call if new value is different
public void paint(Graphics g) {
g.drawImage( ..... blah
if (displayRoute) {
g.drawline ( .... blah
// Then
onActionPerformed
iPanel.setRoute(new Point(1,2), new Point(3,4));

Draw images in different Panels

Hi,
I have a JFrame with three JPanels.
How can I draw three different Buffered images to those three JPanels?
Code is appreciated.

devboris wrote:
Hi,
I have a JFrame with three JPanels.
How can I draw three different Buffered images to those three JPanels?Do you know how to draw one BufferedImage in one JPanel? If not, start there.
Code is appreciated.An [SSCCE |http://sscce.org] is appreciated.

How can I display an image in AWT Panel

notes: I can't use swing, don't tell me something relate to swing, I need to use pure AWT

Load it with [url http://java.sun.com/j2se/1.5.0/docs/api/java/awt/Toolkit.html#createImage(java.net.URL)]Toolkit.createImage or [url http://java.sun.com/j2se/1.5.0/docs/api/javax/imageio/ImageIO.html]ImageIO
Subclass Canvas
[url http://java.sun.com/j2se/1.5.0/docs/api/java/awt/Graphics.html#drawImage(java.awt.Image,%20int,%20int,%20java.awt.image.ImageObserver)]Graphics.drawImage

Want to draw some rectangles inside a swing panel object

HI,
I want to draw some rectangles inside one JPanel object in swing. The JPanel object should also hold some buttons, labels, etc.. I can add simple buttons, label etc. easily to the panel object but how do I add graphics (like lines, rectangles) to it ??
an immediate response would be highly appreciated!!

I am not sure why you are talking about the rectangle.
To repeat I fill in a bit of code (subject to compiler errors since I Do not have a machine where I can compile or test on at the moment):
private class ColourCube extends JPanel
     // The size of each rectangle with colour
     private static final int ROWS = 10;
     private static final int COLS = 10;
     // To store current selection
     private int selectedIndex[] = null;
     public ColourCube()
         addMouseListener( new MouseAdapter() {
            public void mouseReleased(MouseEvent me)
               // Find the rectangle index by dividing
               // x and y positions then set selectedIndex
               // unless it is the same positions as previous
               // then set it to be null
               fireActionEvent();
     // needed listener methods for firing events
     public void addActionListener( ActionListener al)
        // add to list
     // remove etc....
     protected void fireActionEvent()
        // Construct action event
        // call actionPerformed( ae ) on all listeners
     public void paintComponent(Graphics g)
         // Depending on size and height of this component
         // calculate out colWidth and rowHeight
         // Loop and paint the rectangles in their different colours
         for(int i = 0; i < ROWS; i++)
            for(int j = 0; j < COLS; j++)
               // set the colour to the graphics object here from the list of colours available
               g.setColor( ... );
               // Added a little bit extra to have some space between
               // each rectangle
               g.fillRect( i * rowHeight + 1, j * colWidth + 1, colWidth - 2, rowHeight - 2 );
         if( selectedIndex != null )
            // We have a selection, lets paint the selection
            g.setColor( Color.white ); // Selection colour
            // The index contains the row in index 0 and the col in index 1
            g.drawRect( selectedIndex[0] * rowHeight, selectedIndex[1] * colWidth, colWidth, rowHeight );
}Lacking from the above component is lacking stuff like preferedSize.
Now, all you do is instantiate the ColourChooser, add it to your applet iether by drag and drop if you have an WYSIWYG editor, or by hand if you are so inclined.
Voila! A composite component appears, doing the stuff it needs to be doing.
Regards,
Peter Norell

How to drag image in left panel then drop into right panel??

Dear friends.
I have following code, it is runnable, just add two jpg image files is ok, to run.
I tried few days to drag image from left panel then drop into right panel or vice versa, but not success, can any GUI guru help??
Thanks.
Sunny
[1]. main code/calling code:
import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class ImagePanelCall extends JComponent {
     public JSplitPane ImagePanelCall() {
          setPreferredSize(new Dimension(1200,300));
          JSplitPane          sp = new JSplitPane();
          sp.setPreferredSize(new Dimension(1200,600));
          sp.setOrientation(JSplitPane.HORIZONTAL_SPLIT);
          add(sp);
          ImagePanel     ip = new ImagePanel();
          ImagePanel     ip1 = new ImagePanel();
          ip.setPreferredSize(new Dimension(600,300));
          ip1.setPreferredSize(new Dimension(600,300));
          sp.setLeftComponent(ip);// add left part
          sp.setRightComponent(ip1);// add right part
          sp.setVisible(true);
          return sp;
     public static void main(String[] args) {
          JFrame frame = new JFrame("Test transformable images");
          ImagePanelCall ic = new ImagePanelCall();
          frame.setPreferredSize(new Dimension(1200,600));
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.getContentPane().add(ic.ImagePanelCall(), BorderLayout.CENTER);
          frame.pack();
          frame.setVisible(true);
}[2]. code 2
import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class ImagePanel extends JComponent {
     private static final Cursor DEFAULT_CURSOR = new Cursor(Cursor.DEFAULT_CURSOR);
     private static final Cursor MOVE_CURSOR = new Cursor(Cursor.MOVE_CURSOR);
     private static final Cursor VERTICAL_RESIZE_CURSOR = new Cursor(Cursor.N_RESIZE_CURSOR);
     private static final Cursor HORIZONTAL_RESIZE_CURSOR = new Cursor(Cursor.W_RESIZE_CURSOR);
     private static final Cursor NW_SE_RESIZE_CURSOR = new Cursor(Cursor.NW_RESIZE_CURSOR);
     private static final Cursor NE_SW_RESIZE_CURSOR = new Cursor(Cursor.NE_RESIZE_CURSOR);
     public Vector images;
     * Create an ImagePanel with two images in.
     * A MouseHandler instance is added as mouse listener and mouse motion listener.
     public ImagePanel() {
          images = new Vector();
          images.add(new TransformableImage("swing/dnd/Bird.gif"));
          images.add(new TransformableImage("swing/dnd/Cat.gif"));
          setPreferredSize(new Dimension(600,600));
          MouseHandler mh = new MouseHandler();
          addMouseListener(mh);
          addMouseMotionListener(mh);
     * Simply paint all the images contained in the Vector images, calling their method draw(Graphics2D, ImageObserver).
     public void paintComponent(Graphics g) {
          Graphics2D g2D = (Graphics2D)g;
          for (int i = images.size()-1; i>=0; i--) {
               ((TransformableImage)images.get(i)).draw(g2D, this);
     * Inner class defining the behavior of the mouse.
     final class MouseHandler extends MouseInputAdapter {
          private TransformableImage draggedImage;
          private int transformation;
          private int dx, dy;
          public void mouseMoved(MouseEvent e) {
               Point p = e.getPoint();
               TransformableImage image = getImageAt(p);
               if (image != null) {
                    transformation = image.getTransformation(p);
                    setConvenientCursor(transformation);
               else {
                    setConvenientCursor(-1);
          public void mousePressed(MouseEvent e) {
               Point p = e.getPoint();
               draggedImage = getImageAt(p);
               if (draggedImage!=null) {
                    dx = p.x-draggedImage.x;
                    dy = p.y-draggedImage.y;
          public void mouseDragged(MouseEvent e) {
               if (draggedImage==null) {
                    return;
               Point p = e.getPoint();
               repaint(draggedImage.x,draggedImage.y,draggedImage.width+1,draggedImage.height+1);
               draggedImage.transform(p, transformation,dx,dy);
               repaint(draggedImage.x,draggedImage.y,draggedImage.width+1,draggedImage.height+1);
          public void mouseReleased(MouseEvent e) {
               Point p = e.getPoint();
               draggedImage = null;
     * Utility method used to get the image located at a Point p.
     * Returns null if there is no image at this point.
     private final TransformableImage getImageAt(Point p) {
          TransformableImage image = null;
          for (int i = 0, n = images.size(); i<n; i++) {
               image = (TransformableImage)images.get(i);
               if (image.contains(p)) {
                    return(image);
          return(null);
     * Sets the convenient cursor according the the transformation (i.e. the position of the mouse over the image).
     private final void setConvenientCursor(int transfo) {
          Cursor currentCursor = getCursor();
          Cursor newCursor = null;
          switch (transfo) {
               case TransformableImage.MOVE : newCursor = MOVE_CURSOR;
                    break;
               case TransformableImage.RESIZE_TOP : newCursor = VERTICAL_RESIZE_CURSOR;
                    break;
               case TransformableImage.RESIZE_BOTTOM : newCursor = VERTICAL_RESIZE_CURSOR;
                    break;
               case TransformableImage.RESIZE_LEFT : newCursor = HORIZONTAL_RESIZE_CURSOR;
                    break;
               case TransformableImage.RESIZE_RIGHT : newCursor = HORIZONTAL_RESIZE_CURSOR;
                    break;
               case TransformableImage.RESIZE_TOP_LEFT_CORNER : newCursor = NW_SE_RESIZE_CURSOR;
                    break;
               case TransformableImage.RESIZE_TOP_RIGHT_CORNER : newCursor = NE_SW_RESIZE_CURSOR;
                    break;
               case TransformableImage.RESIZE_BOTTOM_LEFT_CORNER : newCursor = NE_SW_RESIZE_CURSOR;
                    break;
               case TransformableImage.RESIZE_BOTTOM_RIGHT_CORNER : newCursor = NW_SE_RESIZE_CURSOR;
                    break;
               default : newCursor = DEFAULT_CURSOR;
          if (newCursor != null && currentCursor != newCursor) {
               setCursor(newCursor);
     public static void main(String[] args) {
          JFrame frame = new JFrame("Test transformable images");
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.getContentPane().add(new ImagePanel(), BorderLayout.CENTER);
          frame.pack();
          frame.setVisible(true);
}[3]. code 3
import java.awt.*;
import javax.swing.*;
import java.awt.image.*;
public final class TransformableImage extends Rectangle {
     public static final int MOVE = 0;
     public static final int RESIZE_TOP = 10;
     public static final int RESIZE_BOTTOM = 20;
     public static final int RESIZE_RIGHT = 1;
     public static final int RESIZE_LEFT = 2;
     public static final int RESIZE_TOP_RIGHT_CORNER = 11;
     public static final int RESIZE_TOP_LEFT_CORNER = 12;
     public static final int RESIZE_BOTTOM_RIGHT_CORNER = 21;
     public static final int RESIZE_BOTTOM_LEFT_CORNER = 22;
     public static final int BORDER_THICKNESS = 5;
     public static final int MIN_THICKNESS = BORDER_THICKNESS*2;
     private static final Color borderColor = Color.black;
     private Image image;
     * Create an TransformableImage from the image file filename.
     * The TransformableImage bounds (inherited from the class Rectangle) are setted to the corresponding values.
     public TransformableImage(String filename) {
          ImageIcon ic = new ImageIcon(filename);
          image = ic.getImage();
          setBounds(0,0,ic.getIconWidth(), ic.getIconHeight());
     * Draw the image rescaled to fit the bounds.
     * A black rectangle is drawn around the image.
     public final void draw(Graphics2D g, ImageObserver observer) {
          Color oldColor = g.getColor();
          g.setColor(borderColor);
          g.drawImage(image, x, y, width, height, observer);
          g.draw(this);
          g.setColor(oldColor);
     * Return an int corresponding to the transformation available according to the mouse location on the image.
     * If the point p is in the border, with a thickness of BORDER_THICKNESS, around the image, the corresponding
     * transformation is returned (RESIZE_TOP, ..., RESIZE_BOTTOM_LEFT_CORNER).
     * If the point p is located in the center of the image (i.e. out of the border), the MOVE transformation is returned.
     * We allways suppose that p is contained in the image bounds.
     public final int getTransformation(Point p) {
          int px = p.x;
          int py = p.y;
          int transformation = 0;
          if (py<(y+BORDER_THICKNESS)) {
               transformation += RESIZE_TOP;
          else
          if (py>(y+height-BORDER_THICKNESS-1)) {
               transformation += RESIZE_BOTTOM;
          if (px<(x+BORDER_THICKNESS)) {
               transformation += RESIZE_LEFT;
          else
          if (px>(x+width-BORDER_THICKNESS-1)) {
               transformation += RESIZE_RIGHT;
          return(transformation);
     * Move the left side of the image, verifying that the width is > to the MIN_THICKNESS.
     public final void moveX1(int px) {
          int x1 = x+width;
          if (px>x1-MIN_THICKNESS) {
               x = x1-MIN_THICKNESS;
               width = MIN_THICKNESS;
          else {
               width += (x-px);
               x = px;
     * Move the right side of the image, verifying that the width is > to the MIN_THICKNESS.
     public final void moveX2(int px) {
          width = px-x;
          if (width<MIN_THICKNESS) {
               width = MIN_THICKNESS;
     * Move the top side of the image, verifying that the height is > to the MIN_THICKNESS.
     public final void moveY1(int py) {
          int y1 = y+height;
          if (py>y1-MIN_THICKNESS) {
               y = y1-MIN_THICKNESS;
               height = MIN_THICKNESS;
          else {
               height += (y-py);
               y = py;
     * Move the bottom side of the image, verifying that the height is > to the MIN_THICKNESS.
     public final void moveY2(int py) {
          height = py-y;
          if (height<MIN_THICKNESS) {
               height = MIN_THICKNESS;
     * Apply a given transformation with the given Point to the image.
     * The shift values dx and dy are needed for move tho locate the image at the same relative position from the cursor (p).
     public final void transform(Point p, int transformationType, int dx, int dy) {
          int px = p.x;
          int py = p.y;
          switch (transformationType) {
               case MOVE : x = px-dx; y = py-dy;
                    break;
               case RESIZE_TOP : moveY1(py);
                    break;
               case RESIZE_BOTTOM : moveY2(py);
                    break;
               case RESIZE_LEFT : moveX1(px);
                    break;
               case RESIZE_RIGHT : moveX2(px);
                    break;
               case RESIZE_TOP_LEFT_CORNER : moveX1(px);moveY1(py);
                    break;
               case RESIZE_TOP_RIGHT_CORNER : moveX2(px);moveY1(py);
                    break;
               case RESIZE_BOTTOM_LEFT_CORNER : moveX1(px);moveY2(py);
                    break;
               case RESIZE_BOTTOM_RIGHT_CORNER : moveX2(px);moveY2(py);
                    break;
               default :
}

I gave you a simple solution in your other posting. You never responded to the suggestion stating why the given solution wouldn't work, so it can't be that urgent.

How to make image out of panel?

hi,
i have a JPanel object and i drawn something on this panel. it also contains somemore components. can anyone say how to create image (like .jpg) from what is getting displayed in my panel.
thankx in advance.

Found this in the newgroups
If you are using Java 2D, you can create a JPEG image by using the
com.sun.image.codec.jpeg package. The code below creates a JPEG image and
saves it to a file.
public void save(BufferedImage destImage, String filename) {
try {
ByteArrayOutputStream boutstream = new ByteArrayOutputStream();
JPEGImageEncoder enc = JPEGCodec.createJPEGEncoder(boutstream);
enc.encode(destImage);
FileOutputStream fimage = new FileOutputStream(new File(filename));
boutstream.writeTo(fimage);
fimage.close();
} catch (Exception e) { }
The code snippet below shows how to crerate a BufferedImage:
BufferedImage bi = new BufferedImage((int)imWid,
(int)(imHt),
BufferedImage.TYPE_INT_RGB);
Graphics2D g2d = bi.createGraphics();
g2d.drawImage(img, dispTx,this);
img : Your image object.
dispTx: The Affine Transform.
You can use other drawImage()methods for drawing images.
Once the image is drawn, you can save it using the save() method.

Getting the bounds of a drawn image on a panel

Hello, I have a problem with getting the bounds of a drawn image on a panel...Since it is drawn as graphics, i tried getClipBounds and since my class extends JPanel i tried to get the bounds from the panel but neither of them worked properly. It only gets the bounds of a jframe that contains the panel.Then i tried to put the panel in a layeredpane and then a container; but this time the image disappeared completely. Hope someone can help or tell me what I am doing wrong. Thanks in advance. Here is the code below:
By the way what I am trying to do in this code is basically zooming the image in and out by dragging or the mouse wheel. But I need to get the bounds so that I can use this.
* To change this template, choose Tools | Templates
* and open the template in the editor.
* @author Admin
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.Toolkit;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.event.MouseWheelEvent;
import java.awt.event.MouseWheelListener;
import java.awt.geom.AffineTransform;
import java.awt.geom.NoninvertibleTransformException;
import java.awt.geom.Point2D;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
public class ZoomDemo extends JPanel {
AffineTransform tx = new AffineTransform();
String imagePath = "D:/Documents and Settings/Admin/Belgelerim/tsrm/resim.jpg";
Image image = Toolkit.getDefaultToolkit().getImage(imagePath);
int width = image.getWidth(this);
int height = image.getHeight(this);
int scrwidth = Toolkit.getDefaultToolkit().getScreenSize().width;
int scrheight = Toolkit.getDefaultToolkit().getScreenSize().height;
double zoomfac = 1.0;
int xAdj;
int yAdj;
int prevY;
double scale = 1.0;
Point pt;
public static int x;
public static int y;
public static int w;
public static int h;
public ZoomDemo() {
this.addMouseWheelListener(new ZoomHandler());
this.addMouseListener(new ZoomHandler());
this.addMouseMotionListener(new ZoomHandler());
repaint();
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.drawImage(image, tx, this);
// x =    (int) g2.getClipBounds().getX();
// y=     (int) g2.getClipBounds().getY();
// w=     (int) g2.getClipBounds().getWidth();
// h=     (int) g2.getClipBounds().getHeight();
// System.out.println(x+" "+y+" "+w+" "+h);
// public int getRectx(){
//    return x;
//public int getRecty(){
//    return y;
//public int getRectw(){
//    return w;
//public int getRecth(){
//    return h;
private class ZoomHandler implements MouseWheelListener,MouseListener, MouseMotionListener {
public void mousePressed(MouseEvent e){
    System.out.println("Mouse Pressed");
xAdj = e.getX();
yAdj = e.getY();
prevY = getY();
public void mouseDragged(MouseEvent e){
       System.out.println("Mouse Dragged");
boolean zoomed = false;
if(e.getY()<prevY){
     zoomfac = zoomfac + 0.1;
     prevY = e.getY();
     zoomed = true;
else if(e.getY()>prevY){
     zoomfac = zoomfac - 0.1;
     prevY = e.getY();
     zoomed = true;
   scale = zoomfac;
Point2D p1 = new Point((int)xAdj-(width/2),(int)yAdj-(height/2));
Point2D p2 = null;
try {
p2 = tx.inverseTransform(p1, null);
} catch (NoninvertibleTransformException ex) {
// should not get here
ex.printStackTrace();
return;
tx.setToIdentity();
tx.translate(p1.getX(), p1.getY());
tx.scale(scale, scale);
tx.translate(-p2.getX(), -p2.getY());
tx.transform(p1, p2);
ZoomDemo.this.revalidate();
ZoomDemo.this.repaint();
public void mouseWheelMoved(MouseWheelEvent e) {
if (e.getScrollType() == MouseWheelEvent.WHEEL_UNIT_SCROLL) {
Point2D p1 = e.getPoint();
Point2D p2 = null;
try {
p2 = tx.inverseTransform(p1, null);
} catch (NoninvertibleTransformException ex) {
// should not get here
ex.printStackTrace();
return;
scale -= (0.1 * e.getWheelRotation());
scale = Math.max(0.1, scale);
tx.setToIdentity();
tx.translate(p1.getX(), p1.getY());
tx.scale(scale, scale);
tx.translate(-p2.getX(), -p2.getY());
ZoomDemo.this.revalidate();
ZoomDemo.this.repaint();
        public void mouseClicked(MouseEvent e) {
            //throw new UnsupportedOperationException("Not supported yet.");
        public void mouseReleased(MouseEvent e) {
            //throw new UnsupportedOperationException("Not supported yet.");
        public void mouseEntered(MouseEvent e) {
           // throw new UnsupportedOperationException("Not supported yet.");
        public void mouseExited(MouseEvent e) {
           // throw new UnsupportedOperationException("Not supported yet.");
        public void mouseMoved(MouseEvent e) {
           // throw new UnsupportedOperationException("Not supported yet.");
public static void main(String[] args) {
//SwingUtilities.invokeLater(new ZoomDemo());
int scrwidth = Toolkit.getDefaultToolkit().getScreenSize().width;
int scrheight = Toolkit.getDefaultToolkit().getScreenSize().height;
JFrame f = new JFrame("Zoom");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(scrwidth , scrheight);
//JLayeredPane lp = new JLayeredPane();
//f.add(lp);
ZoomDemo zd = new ZoomDemo();
zd.getBounds();
f.add(zd);
//int x = (int) zd.getX();
//int y = (int) zd.getY();
//int w = (int) zd.getWidth();
//int h = (int) zd.getHeight();
//System.out.println(x+" "+y+" "+w+" "+h);
//zd.setBounds(x ,y ,w ,h );
//lp.add(zd, JLayeredPane.DEFAULT_LAYER);
//f.setLocationRelativeTo(null);
f.setVisible(true);
//lp.setVisible(true);
//zd.setVisible(true);
}Edited by: .mnemonic. on May 26, 2009 11:07 PM
Edited by: .mnemonic. on May 27, 2009 11:00 AM

You'll need a stable point in the component to track and orient to the scaling transform(s).
From this you can construct whatever you need in the way of image location and size.
Let's try a center–of–image tracking point:
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
import javax.swing.event.MouseInputAdapter;
public class ZD extends JPanel {
    BufferedImage image;
    Point center;
    AffineTransform at = new AffineTransform();
    Point2D.Double origin = new Point2D.Double(0,0);
    public ZD(BufferedImage image) {
        this.image = image;
        center = new Point(image.getWidth()/2, image.getHeight()/2);
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2 = (Graphics2D)g;
        g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
                            RenderingHints.VALUE_INTERPOLATION_BICUBIC);
        g2.drawRenderedImage(image, at);
        g2.setPaint(Color.red);
        g2.fill(new Ellipse2D.Double(origin.x-1.5, origin.y-1.5, 4, 4));
        g2.setPaint(Color.blue);
        g2.fill(new Ellipse2D.Double(center.x-1.5, center.y-1.5, 4, 4));
    private void setTransform(double scale) {
        // keep image centered over Point "center"
        double x = center.x - scale*image.getWidth()/2;
        double y = center.y - scale*image.getHeight()/2;
        origin.setLocation(x, y);
        at.setToTranslation(x, y);
        at.scale(scale, scale);
    public static void main(String[] args) throws java.io.IOException {
        java.net.URL url = ZD.class.getResource("images/hawk.jpg");
        BufferedImage image = javax.imageio.ImageIO.read(url);
        ZD test = new ZD(image);
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(test);
        f.setSize(500,500);
        f.setLocation(100,100);
        f.setVisible(true);
        test.addMouseListener(test.mia);
        test.addMouseMotionListener(test.mia);
    /** MouseAdapter okay in j2se 1.6+ */
    private MouseInputAdapter mia = new MouseInputAdapter() {
        final double SCALE_INC = 0.05;
        final int SCALE_STEP = 20;
        double scale = 1.0;
        double lastStep;
        public void mousePressed(MouseEvent e) {
            Point p = e.getPoint();
            center.setLocation(p);
            //System.out.printf("center = [%3d, %3d]%n", p.x, p.y);
            setTransform(scale);
            repaint();
        public void mouseDragged(MouseEvent e) {
            // scale up/down with relative vertical motion
            int step = (e.getY() - center.y)/SCALE_STEP;
            if(step != lastStep) {
                scale += SCALE_INC*((step < lastStep) ? -1 : 1);
                //System.out.printf("step = %3d scale = %.3f%n", step, scale);
                setTransform(scale);
                lastStep = step;
                repaint();
}

How can I draw image in a vbean?

How can I draw image in a vbean?
this is my code :
import java.awt.BorderLayout;
import java.awt.Image;
import java.awt.Graphics;
import java.net.MalformedURLException;
import java.net.URL;
import com.sun.jimi.core.Jimi;
import oracle.forms.handler.IHandler;
import oracle.forms.properties.ID;
import oracle.forms.ui.VBean;
public class PrintEmailLogo extends VBean {
     URL url;
     Image img;
     boolean ImageLoaded = false;
     public void paint(Graphics g) {
          if (ImageLoaded) {
               System.out.println("yes~~~");
               g.drawImage(img, 0, 0, null);
          } else
               System.out.println("no~~~");
     public boolean imageUpdate(Image img, int infoflags, int x, int y, int w,
               int h) {
          if (infoflags == ALLBITS) {
               System.out.println("yes");
               ImageLoaded = true;
               repaint();
               return false;
          } else
               return true;
     public void init(IHandler arg0) {
          super.init(arg0);
          try {
               url = new URL("file:print/77G.gif");
               img = Jimi.getImage(url);
               Image offScreenImage = createImage(size().width, size().height);
               Graphics offScreenGC = offScreenImage.getGraphics();
               System.out.println(offScreenGC.drawImage(img, 0, 0, this));
          } catch (MalformedURLException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
but when I run it in forms
when it run Graphics offScreenGC = offScreenImage.getGraphics();
It throw a exception:
java.lang.NullPointerException     at com.avicit.aepcs.calendar.PrintEmailLogo.init(PrintEmailLogo.java:72)     at oracle.forms.handler.UICommon.instantiate(Unknown Source)     at oracle.forms.handler.UICommon.onCreate(Unknown Source)     at oracle.forms.handler.JavaContainer.onCreate(Unknown Source)     at oracle.forms.engine.Runform.onCreateHandler(Unknown Source)     at oracle.forms.engine.Runform.processMessage(Unknown Source)     at oracle.forms.engine.Runform.processSet(Unknown Source)     at oracle.forms.engine.Runform.onMessageReal(Unknown Source)     at oracle.forms.engine.Runform.onMessage(Unknown Source)     at oracle.forms.engine.Runform.processEventEnd(Unknown Source)     at oracle.ewt.lwAWT.LWComponent.redispatchEvent(Unknown Source)     at oracle.ewt.lwAWT.LWComponent.processEvent(Unknown Source)     at java.awt.Component.dispatchEventImpl(Unknown Source)     at java.awt.Container.dispatchEventImpl(Unknown Source)     at java.awt.Component.dispatchEvent(Unknown Source)     at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)     at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)     at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)     at java.awt.Container.dispatchEventImpl(Unknown Source)     at java.awt.Component.dispatchEvent(Unknown Source)     at java.awt.EventQueue.dispatchEvent(Unknown Source)     at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)     at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)     at java.awt.EventDispatchThread.pumpEvents(Unknown Source)     at java.awt.EventDispatchThread.run(Unknown Source)
I change it to:
import java.awt.BorderLayout;
import java.awt.Image;
import java.awt.Graphics;
import java.net.MalformedURLException;
import java.net.URL;
import javax.swing.JFrame;
import com.sun.jimi.core.Jimi;
import oracle.forms.handler.IHandler;
import oracle.forms.properties.ID;
import oracle.forms.ui.VBean;
public class PrintEmailLogo extends VBean {
     URL url;
     Image img;
     public void paint(Graphics g) {
          try {
               url = new URL("file:print/77G.gif");
               img = Jimi.getImage(url);
               g.drawImage(img, 0, 0, this));
          } catch (MalformedURLException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
     public void init(IHandler arg0) {
          super.init(arg0);
But it display nothing.
It isn't paint continuous.
what's wrong in my vbean?
please help me.

The following code works fine for me:
package oracle.forms.fd;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.util.*;
import javax.swing.*;
import javax.swing.event.*;
import oracle.forms.handler.IHandler;
import oracle.forms.properties.ID;
import oracle.forms.ui.CustomEvent;
import oracle.forms.ui.VBean;
public class test extends VBean {
private URL url;
private URL m_codeBase;
private Image img;
public void paint(Graphics g) {
// draw the image
g.drawImage(img, 0, 0, this);
public void init(IHandler arg0) {
   super.init(arg0);
   // load image file
   img = loadImage("file:///c:/coyote.jpg");
public test()
    super();
   * Load an image from JAR file, Client machine or Internet URL *
private Image loadImage(String imageName)
    URL imageURL = null;
    boolean loadSuccess = false;
    Image img = null ;
    //JAR
    imageURL = getClass().getResource(imageName);
    if (imageURL != null)
      try
        img = Toolkit.getDefaultToolkit().getImage(imageURL);
        loadSuccess = true;
        return img ;
      catch (Exception ilex)
        System.out.println("Error loading image from JAR: " + ilex.toString());
    else
      System.out.println("Unable to find " + imageName + " in JAR");
    //DOCBASE
    if (loadSuccess == false)
      System.out.println("Searching docbase for " + imageName);
      try
        if (imageName.toLowerCase().startsWith("http://")||imageName.toLowerCase().startsWith("https://"))
          imageURL = new URL(imageName);
        else if(imageName.toLowerCase().startsWith("file:"))
          imageURL = new URL(imageName);
        else
          imageURL = new URL(m_codeBase.getProtocol() + "://" + m_codeBase.getHost() + ":" + m_codeBase.getPort() + imageName);
        System.out.println("Constructed URL: " + imageURL.toString());
        try
          img = createImage((java.awt.image.ImageProducer) imageURL.getContent());
          loadSuccess = true;
          System.out.println("Image found: " + imageURL.toString());
          return img ;
        catch (Exception ilex)
          System.out.println("Error reading image - " + ilex.toString());
      catch (java.net.MalformedURLException urlex)
        System.out.println("Error creating URL - " + urlex.toString());
    //CODEBASE
    if (loadSuccess == false)
      System.out.println("Searching codebase for " + imageName);
      try
        imageURL = new URL(m_codeBase, imageName);
        System.out.println("Constructed URL: " + imageURL.toString());
        try
          img = createImage((java.awt.image.ImageProducer) imageURL.getContent());
          loadSuccess = true;
          System.out.println("Image found: " + imageURL.toString());
          return img ;
        catch (Exception ilex)
                System.out.println("Error reading image - " + ilex.toString());
      catch (java.net.MalformedURLException urlex)
        System.out.println("Error creating URL - " + urlex.toString());
    if (loadSuccess == false)
      System.out.println("Error image " + imageName + " could not be located");
    return img ;
}Francois

Creating an image from a panel

Hi everybody,
I have a panel which extends JPanel, and wrote an image() method to extract the drawn image off the panel. For some reason, though, when I call this method, I get a dialog with a black box centered in it, and not the appropriate image.
My SSCCE is as follows:
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import javax.swing.ImageIcon;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
public class MyPanel extends JPanel {
    private BufferedImage image;
    public BufferedImage image() {
        int x = getWidth();
        int y = getHeight();
        //image = new BufferedImage(x, y, BufferedImage.TYPE_INT_RGB);
        image = new BufferedImage(200, 200, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2 = image.createGraphics();
        SwingUtilities.paintComponent( g2, this, new JPanel(), 0, 0, x, y );
        g2.dispose();
        return image;
    public static void main( String args[] ) {
         MyPanel canvas = new MyPanel() {
              public void paintComponent( Graphics g ) {
                   Graphics2D g2 = (Graphics2D)g;
                   for( int i = 1; i <= 20; i++ ) {
                        int pos = i*50;
                        g2.drawString( "This is a test", pos, pos );
         JDialog test = new JDialog();
        JLabel label = new JLabel( new ImageIcon( canvas.image() ) );
        JScrollPane scroller = new JScrollPane( label );
        scroller.setPreferredSize( new Dimension( 500, 500 ) );
        test.add( scroller );
        test.pack();
        test.setVisible( true );
}I'm pretty sure it has something to do with the sizing of the image and the timing of the repainting--when I uncomment the commented line in image(), I get an error saying width and height can't be less than or equal to 0. But anyway, I need to paint and then show an image of what was painted, not the actual painted panel--that's what I'm having trouble with. If anyone could help me out, I'd appreciate it. Can anyone help me fix this, please?
Thanks,
Jezzica85
Edited by: jezzica85 on Jun 1, 2009 6:16 AM

Odd choice to both have the panel with a getImage() method, and also override paintComponent(Graphics).
Here is an alternate form of your code.
import java.awt.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
public class MyPanel extends JPanel {
private BufferedImage image;
public BufferedImage image() {
    int x = 200;
    int y = 200;
    image = new BufferedImage(x,y, BufferedImage.TYPE_INT_RGB);
    Graphics2D g2 = image.createGraphics();
    g2.setColor(Color.yellow);
    g2.fillRect(0,0,x,y);
    g2.setColor(Color.black);
    for( int i = 1; i <= 20; i++ ) {
      int pos = i*50;
      g2.drawString( "This is a test", pos, pos );
    g2.dispose();
    return image;
public static void main( String args[] ) {
    Runnable r = new Runnable() {
      public void run() {
        MyPanel canvas = new MyPanel();
        JDialog test = new JDialog();
        JLabel label = new JLabel( new ImageIcon( canvas.image() ) );
        JOptionPane.showMessageDialog(null, label);
        JScrollPane scroller = new JScrollPane( label );
        scroller.setPreferredSize( new Dimension( 500, 500 ) );
        JOptionPane.showMessageDialog(null, scroller);
    EventQueue.invokeLater(r);
}

I cant get it to work! NullPointerExeption at first awt.Graphics Object

I am writing a game with AWT having it as an applet. I intend NOT to use anything outside of Java 1.1
For my Game i thought that i ATLEAST need the following classes:
MainGame, Level, Unit.
I Started writing Level. wrote a fewe methods for it such as
drawGras(int grastype) And started to write MainGame to see if they would work together. it's is/is going to be my first Java application where i actually know what object orienting is... I have already wrote a game in Java but with out knowing what a class or what object orienting realy is(the game works rather good to) but this time i wanted to use object orienting but came up with problems =( if first posted in "New to Javaprogramming" but they couldn't help me and advice me here
My previous post: http://forum.java.sun.com/thread.jsp?forum=54&thread=290558
Here's my code:
import java.awt.*;
public class MainGame extends java.applet.Applet
     implements Runnable {
     Thread runner;
     Image ImgLevel, ImgUnit;
     public MainGame() {
          Level nr1 = new Level();
          nr1.init();
          nr1.setGround(300);
          nr1.drawGras(1);
          nr1.CalcGraphics();
          nr1.drawSky(1);
          Image ImgLevel = nr1.getLevelImage();
     public void paint(Graphics g) {
          g.drawImage(ImgLevel,0,0,this);
     public void update(Graphics g) {
          paint(g);
     public void init() {
          MainGame Game = new MainGame();
     public void stop() {
          runner = null;
          System.exit(1);
     public void start() {
          if(runner == null) {
               runner = new Thread(this);
               runner.start();
     void Pause(int time) {
         try {
             Thread.sleep(time);
         } catch(InterruptedException e) {
           System.out.println(e.toString());
     public void run() {
          Thread thisThread = Thread.currentThread();
               while(thisThread == runner) {
class Level extends java.applet.Applet {
    Font BigText = new Font("Arial", Font.PLAIN, 36);
    Font Normal = new Font("Arial", Font.PLAIN, 14);
    Font Bold = new Font("Arial", Font.BOLD, 14);
    Graphics GrLevel;
    int pattern, sky, GroundtoWalk, Ground;
    Color BgColor = new Color(166,202,240);
    Color gras1 = new Color(0,255,0);
    Color gras2 = new Color(0,200,0);
    Color gras3 = new Color(0,100,0);
    Image ImgLevel;
    void setBgColor(int r, int g, int b) {
        BgColor = new Color(r,g,b);
    void CalcGraphics() {
        ImgLevel = createImage(800,600);
        GrLevel = ImgLevel.getGraphics();
    void setGround(int GrounD) {
        Ground = GrounD;
    void GroundToWalkADD(int addToGround) {
        GroundtoWalk = Ground + addToGround;
    void setGroundToWalk(int GrToWalk) {
        GroundtoWalk = GrToWalk;
    public void init() {
          System.out.println("Init 1"); // This was placed here when i was checking how far it got when debuging
          CalcGraphics();
          System.out.println("Init 2");
          drawGras(1);
          System.out.println("Init 3");
          repaint();
          System.out.println("Init 4");
    Image getLevelImage() {
        return ImgLevel;
    public void paint(Graphics g) {
          g.drawImage(ImgLevel,0,0,this);
    public void update(Graphics g) {
        paint(g);
    void drawGras(int pt) {
     GrLevel.setColor(BgColor);
     GrLevel.fillRect(0,0,800,600);
     switch(pt) {
          case 1:
               GrLevel.setColor(gras1);
               GrLevel.fillRect(0,GroundtoWalk,800,300);
               GrLevel.setClip(0,GroundtoWalk,800,300);
               for(int i = 0; 890>i;i=i+5) {
                    GrLevel.setColor(gras2);
                    GrLevel.drawLine(0+i,GroundtoWalk,-190+i,GroundtoWalk+300);
               for(int i=950; 0<i; i=i-5) {
                    GrLevel.setColor(gras3);
                    GrLevel.drawLine(890-i,GroundtoWalk,1000-i,GroundtoWalk+300);
          break;
          case 2:
               GrLevel.setColor(gras2);
               GrLevel.fillRect(0,GroundtoWalk+5,800,300);
               for(int i = 0; 890>i;i=i+5) {
                    GrLevel.setColor(gras3);
                    GrLevel.drawLine(0+i,GroundtoWalk,-190+i,GroundtoWalk+300);
               for(int i=950; 0<i; i=i-5) {
                    GrLevel.setColor(gras1);
                    GrLevel.drawLine(890-i,GroundtoWalk,1000-i,GroundtoWalk+300);
          break;
          case 3:
               GrLevel.setColor(gras3);
               GrLevel.fillRect(0,GroundtoWalk+10,800,300);
               for(int i = 0; 800>i; i=i+20) {
                    GrLevel.fillArc(0+i,GroundtoWalk,20,20,180,-180);
          break;
     pattern = pt;
    int getGrasPattern() {
         return pattern;
    void drawSky(int cl) {
            GrLevel.setColor(BgColor);
            GrLevel.fillRect(0,0,800,155);
            switch(cl) {
                case 1:
               for(int y = 0;y<7;y++) {
               for(int x = 0;x<800;x=x+20) {
                            GrLevel.setColor(Color.white);
                            GrLevel.drawArc(x,y*20,20,20,180,180);
                            GrLevel.setColor(Color.red);
                            GrLevel.drawArc(x,y*20+4,20,20,180,180);
                            GrLevel.setColor(Color.yellow);
                            GrLevel.drawArc(x,y*20+2,20,20,180,180);
                            GrLevel.setColor(Color.green);
                            GrLevel.drawArc(x,y*20+8,20,20,180,180);
                            GrLevel.setColor(Color.blue);
                            GrLevel.drawArc(x,y*20+12,20,20,180,180);
                            GrLevel.setColor(Color.pink);
                            GrLevel.drawArc(x,y*20+16,20,20,180,180);
          break;
          case 2:
                    GrLevel.setColor(Color.gray);
          break;
     sky = cl;
     GrLevel.setFont(BigText);
     GrLevel.setColor(Color.black);
     GrLevel.fillRect(0,0,800,50);
     GrLevel.setColor(Color.white);
     GrLevel.drawString("Score Tabel - comming someday",((size().width)/2)-260, 40);
    int getSkyTyp() {
         return sky;
}I tested running the code of class Level by puting it into Level.java and compiled it...ran it with appletviewer and it worked as it was intended to.
But when i compiled it with MainGame... and in the HTML started MainGame.class,.....applet didn't intializeand i got the following error messege:
Init 1
java.lang.NullPointerException
        at Level.CalcGraphics(MainGame.java:84)
        at MainGame.<init>(MainGame.java:11)Line 82: void CalcGraphics() {
Line 83: ImgLevel = createImage(800,600);
Line 84: GrLevel = ImgLevel.getGraphics(); // The First awt.Graphics object
Line 85: }
Line 9:      public MainGame() {
Line 10:     Level nr1 = new Level();
Line 11:     nr1.CalcGraphics(); // calling the method above -> same error first awt.Graphics Object.
If i change it os that "drawGras" comes first it's first awt.Graphics Line will show the same error
Hope some one can and will help me

As per the documentation of
java.awt.Component.createImage(int,int):
Creates an off-screen drawable image to be used for
double buffering.
Parameters:
width - the specified width
height - the specified height
Returns:
an off-screen drawable image, which can be used for
double buffering. The return value may be null if the
component is not displayable. This will always happen
if GraphicsEnvironment.isHeadless() returns true.
Since:
JDK1.0 its not
ImgLevel = createImage(800,600); that's making the problem but The first awt.Graphics Object in class Level, no mather which on it is =((
>
The key part is '...may be null if the component is
not displayable.'
You should put your graphics initialization code in
start(), which will be called when your applet is
ready to go. Before then, your applet is not
displayable. (Also, remember to dispose() your
graphics in your stop() method, if not sooner.)for the part writen above...I'll try to change it like you are saying.
Thanx for your help!

Displaying thumbnail images in another panel when it mouse clicked

hi,
I am using JAI, what i am trying to do is i am decoding the tiff file and creating thumbnail of that images and adding thumbnail images to one panel and enlarged images to another panel using DisplayJAI. Now when i will click i thumbnail images on left panel then that image should be display to another panel on right side. Adding both panel to JSplit panel.
I have no idia how to do it, i tried to do in different way but not able to do that. I hope anybody can give me the hints about this.
Thanks

i am adding thumbnail of all images in left panel and enlarged view of each thumbnail is added in right panel , and what i require that when i click thumbnail in left side it's corresponding enlarged image should be visible, suppose in right panel page no. 1 is visible and when i click thumbnail of 13 page in left panel that should be in viewport of right panel.You should put your right panel inside a JScrollPane and call [scrollRectToVisible() |http://java.sun.com/javase/6/docs/api/javax/swing/JComponent.html#scrollRectToVisible(java.awt.Rectangle)] from your panel. You can put the rectangles corresponding to enlarged images in a hash map with the keys being some unique attribute of your thumbnails in left panel. That will help in getting the rectangle to make visible, real fast. Or, you can just put the rectangles in some array indexed according to the thumbnails in left panel.
I also want to hide the left panel, i think it's possible by Frame.Yes it is possible, but you said you have both your panels in a split pane, so maybe you can use its setDividerLocation() function to hide your left panel.
Thanks!

Display a color image in front panel.

Hi there,
How do I display a color image in front panel? Which graphic indicator should be used to display a color image? I do not want to use Imaq WindDraw.
Thanks in advance.
Hugh

Try this "draw flatten jpg to pic ctrl.vi"
Ian F
Since LabVIEW 5.1... 7.1.1... 2009, 2010
依恩与LabVIEW
LVVILIB.blogspot.com
Attachments:
draw_flatten_jpg_to_pic_ctrl.vi ‏35 KB

Problems drawing images form another class

Ok as the title says I'm having trouble drawing images from a different class. I have a class that represents a plane and it has a draw' method that draws its .gif image.
public void draw (Graphics g)
g.drawImage(planepic , xPos, yPos, null)
then in my main class in the paint method i have
plane.draw(g);
I think my problem is the null for my image observer. I tried using null as my image observer and i got a error saying i can't make a static reference to a non static method.
I've done some research because i never really understood static but i still don't quite get it.
Also when I use this as my image observer i get a error in my plane object.
I also just tried passing and making a object for my main class and i still got the static error.
Any help is appreciated and thanks in advance

Ok as the title says I'm having trouble drawing
images from a different class. I have a class that
represents a plane and it has a draw' method that
draws its .gif image.
public void draw (Graphics g)
g.drawImage(planepic , xPos, yPos, null)
in my main class in the paint method i have
plane.draw(g);
I think my problem is the null for my image observer.
I tried using null as my image observer and i got a
error saying i can't make a static reference to a non
static method. Use a minimal implementation of the ImageObserver to be sure.
public class Plane implements ImageObserver
public boolean imageUpdate(
Image img,int infoFlags,int x,int y,int width,int height)
   switch(infoFlags)
      case ALLBITS:
                return false;
      case SOMEBITS:
                return true;
      default:
            return true;
I've done some research because i never really
understood static but i still don't quite get it.
Also when I use this as my image observer i get a
error in my plane object.
I also just tried passing and making a object for my
main class and i still got the static error.
Any help is appreciated and thanks in advanceWhen you call draw(g) from your other class you hand it a Graphics context that you instantiated somewhere else ie: in another class. Without a more complete example it is really impossible to determine your issue for sure,
but if I was to guess I would say you need to make sure that the Graphics context handed to the draw(Graphics) method was instantiated from a Component that was already visible. ie: Do a f
Frame.createImage() from your parent frame after iyou have already called setVisible(true); In other words I suspect you are making and Image from some other Component that is not yet visible. That however is a guess so if not the issue post the rest of the code or at least a minimal implementation that demonstrates this.
About static:
static means the class/variable is the same throughout ALL classes of that type and if changed in one instance it will change and thus be the same for all instances.
You CAN call static by referencing the base class Object without having to instantiate.
ie:given
public class SomeClass
static String name;
static String getName
   if(name == null)
      name = "DefaultName";
   return name;
}Thus you could call..
String name = SomeClass.getName();As opposed to
SomeClass myClass = new SomeClass();
      myClass.getName();This can get you in trouble if you try to make a method that is static
that then tries to reference non static variables.
ie:
public class SomeClass
int x;
static String name;
SomeClass()
   x=0;
static String getName
   if(name == null)
      name = "DefaultName";
   x++;
   return name;
}In this case SomeClass.getName(); will throw and exception because it is trying to access[b] x from a static context .
Hope that clears that up for you; if not post a more complete example.
Good Luck!
(T)

Can i print a string on a panel object?

I have been trying to find a way to print a sring on a panel object but
i couldnt manage it. Can this be done? If it can be, how can i do it?

import java.awt.*;
public class Example extends Panel {
public void paint(Graphics g) {
g.drawString("hi there",10,10);
}

Drawing Images in awt Panel object

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