How to set background Image of JOptionPane? I want to show a different image on background of an JOptionPane.
You could extend the JOptionPane class and override the paint method.
Edit:
Depending on the image resolution and quality you might be able to stretch it with an AffineTransform during the WindowResize events without to much distortion. This would let you handle the JOptionPane and image size discrepancies mentioned below.
class ImageBackgroundPane extends JOptionPane
{
private BufferedImage img;
public ImageBackgroundPane (BufferedImage image)
{
this.img = image;
}
#Override
public void paint(Graphics g)
{
//Pick one of the two painting methods below.
//Option 1:
//Define the bounding region to paint based on image size.
//Be careful, if the image is smaller than the JOptionPane size you
//will see a solid white background where the image does not reach.
g.drawImage(img, 0, 0, img.getWidth(), img.getHeight());
//Option 2:
//If the image can be guaranteed to be larger than the JOptionPane's size
Dimension curSize = this.getSize();
g.drawImage(img, 0, 0, curSize.width, curSize.height, null);
//Make sure to paint all the other properties of Swing components.
super.paint(g);
}
}
Related
I am writing a program that consists of three different panels.
This is part of my bottom panel. I display an image using BufferedImage, and I would like to create some text that will appear around 350px into the image, and 15px down. I cannot manage to get this to work and overlay over the bufferedImage.
My current code is as follows (For the bottom panel):
public class BtmPanel extends JPanel {
BtmPanel(){
try {
JLabel imgLabel = new JLabel();
final BufferedImage img = ImageIO.read(new File("image.png"));
ImageIcon icon = new ImageIcon(img);
imgLabel.setIcon(icon);
this.add(imgLabel);
}
catch(IOException ie){
System.out.println("image does not exist");
}
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawString("Y: " + MiddlePanel.y ,350,15);
}
}
There are a couple of ways you might achieve this, depending on your needs and desires.
For example, rather than using a JLabel to display the image, you could paint it directly yourself, for example...
public class BtmPanel extends JPanel {
private BufferedImage image;
BtmPanel(){
try {
image = ImageIO.read(new File("image.png"));
}
catch(IOException ie){
System.out.println("image does not exist");
}
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (image != null) {
g.drawImage(0, 0, image, this);
}
g.drawString("Y: " + MiddlePanel.y ,350,15);
}
}
The reason for doing it this way is you don't (really) control the placement of the image within a JLabel (lots of things can affect it's positioning).
Another solution would be to draw the text directly onto the BufferedImage itself. Which you would use would depend on how dynamic the text might be and a bunch of other factors
A way to do this is doing the exact inverse of your example, overriding the JPanel's paint method painting a BufferedImage (creating a background with your image), and then you can normally add the JLabel with text on your JPanel extension.
Please note that if JPanel is resized and you don't want to have a bad quality background, you'll have to manually create a resized version to adapt the container, or, at least, resize your buffered image with a little logic to keep Width/Height ratio... not that easy!
For the basic version you can try something like the following (taken from a working example) paintComponent overridden function:
#Override
protected void paintComponent(Graphics g) {
Image background = backgroundImage.getScaledInstance(this.getWidth(), this.getHeight(), Image.SCALE_DEFAULT);
super.paintComponent(g);
if (backgroundImage != null) {
g.drawImage(background, 0, 0, null);
}
}
Hope this helps ;)
I have an imagepanel class that draws an image on a JPanel. My problem is that the image appears to be very small inside the jpanel, and I dont know why.
I have done all I could and searched the net and even some java books for this little problem but to no success. I really need some help on this one.
I am extremely new to java.
class Weapons extends JPanel {
private Image weaponimage = weapon1.getImage();
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (image != null)
g.drawImage(weaponimage, 0, 0, getWidth(), getHeight(), this);
}
}
that's the image class.
The 'instant fix' is to paint that element at its natural size. E.G. Change this:
g.drawImage(weaponimage, 0, 0, getWidth(), getHeight(), this);
To this:
g.drawImage(weaponimage, 0, 0, this);
Which seems logical. A 'weapon' should probably be drawn at natural size.
..problem is that the image appears to be very small inside the jpanel,
No. The problem seems to be that the panel itself is very small. The image is painted the width and height of the panel as assigned by the layout.
To increase the size of the (BG) image, add components to the panel (properly laid out) and display the panel at its preferred size.
May be your class look like this:
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import javax.swing.JPanel;
class Weapons extends JPanel {
// get image according to your application logic
BufferedImage image;
#Override
public void paint(Graphics g){
super.paintComponent(g);
g.drawImage(image, 0, 0, getWidth() - 1, getHeight() - 1, 0, 0, image.getWidth() - 1, image.getHeight() - 1, null);
}
public void setImage(BufferedImage image){
this.image = image;
}
}
class Main {
Weapons weapons;
public void updateWeapons(){
// create image
BufferedImage image = new BufferedImage(100, 100, BufferedImage.TYPE_3BYTE_BGR);
// draw on image
// TO UPDATE WEAPONS GUI, below steps are impotant
weapons.setImage(image);
weapons.repaint();
}
}
You have to override paint() method. Then you can set image and call repaint() to update graphics on panel.
use a dimension object to change the size of the image
Weapons picture = new Weapons();
picture.setPreferredSize(new Dimension(110, 160));
panel.add(picture);
do this and you can stretch the length and breadth of your photo as needed.
I have a PNG image with transparency. I used the format because only PNG can support transparency and alpha masks.
My aim is to paint a JPanel with this image and let the transparent regions have the color of the underlying panel, And ultimately do some animations with the image.
How ever I am facing problems, the transparent regions turn out to be solid white color when loaded and painted on the JPanel.
So java does not support transparent images?
class imgpanel extends JPanel{
BufferedImage image,backg;
imgpanel(){
try {
image = ImageIO.read(new File("theimage.png"));
backg = ImageIO.read(new File("backimage.png"));
} catch (IOException ex) {
System.out.println("No image found");
}
setPreferredSize(new Dimension(400,300));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(backg,0,0,null);
g.drawImage(image, 0, 0, null);
}
}
Thus I am painting the transparent "theimage" onto the opaque "backimage"
Yes no problem, do not use palettes, indexed colors.
Try out, whether the images really are transparent, have an alpha component in the color.
For instance with a test.html:
<html>
<body>
<div style="background: url(backimage.png)"><img src="theimage.png"></div>
</body>
</html>
From my experience ImageIO.read loads the image without the transparency by picking wrong transparency/image type. Therefore I use a workaround - ImageIcon to load it as an Image, which can be drawn into empty BufferedImage with predefined image type BufferedImage.TYPE_INT_ARGB. And don't forget ImageIcon forbids the garbage collector to collect the Image, if the image is not flushed afterwards.
ImageIcon imageIcon = new ImageIcon(imageAbsolutePath);
Image tmpImage = imageIcon.getImage();
BufferedImage image = new BufferedImage(imageIcon.getIconWidth(), imageIcon.getIconHeight(), BufferedImage.TYPE_INT_ARGB);
image.getGraphics().drawImage(tmpImage, 0, 0, null);
tmpImage.flush();
return image;
I am using the JScrollNavigator component described here, in order to provide a navigation window onto a large "canvas-like" CAD component I have embedded within a JScrollPane.
I have tried to adapt the JScrollNavigator to draw a thumbnail image of the canvas to provide some additional context to the user. However, the action of doing this causes the rendering of my application's main frame to become corrupted. Specifically, it is the action of calling paint(Graphics) on the viewport component (i.e. my main canvas), passing in the Graphics object created by the BufferedImage that causes subsequent display corruption; if I comment this line out everything works fine.
Below is the JScrollNavigator's overridden paintComponent method:
#Override
protected void paintComponent(Graphics g) {
Component view = jScrollPane.getViewport().getView();
BufferedImage img = new BufferedImage(view.getWidth(), view.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = img.createGraphics();
// Paint JScrollPane view to off-screen image and then scale.
// It is this action that causes the display corruption!
view.paint(g2d);
g2d.drawImage(img, 0, 0, null);
Image scaled = img.getScaledInstance(getWidth(), getHeight(), 0);
super.paintComponent(g);
g.drawImage(scaled, 0, 0, null);
}
Does anyone have any suggestions as to the cause of the corruption? I would have thought that painting to an offscreen image should have no effect on existing paint operations.
EDIT
To provide some additional detail: The JScrollNavigator forms a sub-panel on the left-hand side of a JSplitPane. The JScrollPane associated with the navigator is on the right-hand side. The "corruption" causes the splitter to no longer be rendered and the scrollbars to not be visible (they appear white). If I resize the JFrame, the JMenu section also becomes white. If I attempt to use the navigator or interact with the scrollbars, they become visible, but the splitter remains white. It's as if the opaque settings of the various components has been affected by the rendering of the viewport view to an offscreen image.
Also, if I make the JScrollNavigator appear in a completely separate JDialog, everything works correctly.
EDIT 2
I can reproduce the problem consistently by doing the following:
Add a JMenuBar to the mFrame:
JMenuBar bar = new JMenuBar();
bar.add(new JMenu("File"));
mFrame.setJMenuBar(bar);
In the main() method of JScrollNavigator replace:
jsp.setViewportView(textArea);
... with:
jsp.setViewportView(new JPanel() {
{
setBackground(Color.GREEN);
setBorder(BorderFactory.createLineBorder(Color.BLACK, 5));
}
});
Ensure that the JScrollNavigator is embedded as a panel within mFrame, rather than appearing as a separate JDialog:
mFrame.add(jsp, BorderLayout.CENTER);
mFrame.add(nav, BorderLayout.NORTH);
Now when the application runs the JMenuBar is no longer visible; the act of painting the view (i.e. a green JPanel with thick black border) to the Graphics2D returned by BufferedImage.createGraphics() actually appears to be rendering it onscreen, possibly from the top-left corner of the JFrame, thus obscuring other components. This only seems to happen if a JPanel is used as the viewport view, and not another component such as JTextArea, JTable, etc.
EDIT 3
Looks like this person was having the same problem (no solution posted though): http://www.javaworld.com/community/node/2894/
EDIT 4
Here's the main and paintComponent methods that result in the reproducible error described in Edit 2:
public static void main(String[] args) {
JScrollPane jsp = new JScrollPane();
jsp.setViewportView(new JPanel() {
{
setBackground(Color.GREEN);
setBorder(BorderFactory.createLineBorder(Color.BLACK, 5));
}
});
JScrollNavigator nav = new JScrollNavigator();
nav.setJScrollPane(jsp);
JFrame mFrame = new JFrame();
JMenuBar bar = new JMenuBar();
bar.add(new JMenu("File"));
mFrame.setJMenuBar(bar);
mFrame.setTitle("JScrollNavigator Test");
mFrame.setSize(800, 600);
mFrame.setLayout(new GridLayout(1, 2));
mFrame.add(jsp);
mFrame.add(nav);
Dimension screenDim = Toolkit.getDefaultToolkit().getScreenSize();
mFrame.setLocation((screenDim.width - mFrame.getSize().width) / 2, (screenDim.height - mFrame.getSize().height) / 2);
mFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mFrame.setVisible(true);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Component view = jScrollPane.getViewport().getView();
if (img == null) {
GraphicsConfiguration gfConf = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice().getDefaultConfiguration();
img = new BufferedImage(view.getWidth(), view.getHeight(), BufferedImage.TYPE_INT_ARGB);
}
Graphics2D g2d = img.createGraphics();
view.paint(g2d);
Image scaled = img.getScaledInstance(getWidth(), getHeight(), 0);
g.drawImage(scaled, 0, 0, null);
}
EDIT 5
It seems like others are having trouble recreating the exact problem. I would ask people to run the code pasted here. When I first run this example I see the following:
Neither the JScrollNavigator or the JMenuBar have been painted; these frame areas are transparent.
After resizing I see the following:
The JMenuBar has still not been painted and it appears that the JPanel was at some point rendered at (0,0) (where the JMenuBar should be). The view.paint call within paintComponent is the direct cause of this.
Summary: The original JScrollNavigator uses the Swing opacity property to render a convenient green NavBox over a scaled thumbnail of the component in an adjacent JScrollPane. Because it extends JPanel, the (shared) UI delegate's use of opacity conflicts with that of the scrollable component. The images seen in edit 5 above typify the associated rendering artifact, also shown here. The solution is to let NavBox, JScrollNavigator and the scrollable component extend JComponent, as suggested in the second addendum below. Each component can then manage it's own properties individually.
I see no unusual rendering artifact with your code as posted on my platform, Mac OS X, Java 1.6. Sorry, I don't see any glaring portability violations.
A few probably irrelevant, but perhaps useful, observations.
Even if you use setSize(), appropriately in this case, you should still pack() the enclosing Window.
f.pack();
f.setSize(300, 200);
For convenience, add() forwards the component to the content pane.
f.add(nav, BorderLayout.WEST);
Prefer StringBuilder to StringBuffer.
Consider ComponentAdapter in place of ComponentListener.
Addendum: As suggested here, I got somewhat more flexible results using RenderingHints instead of getScaledInstance() as shown below. Adding a few icons makes it easier to see the disparate effect on images and text.
editPane.insertIcon(UIManager.getIcon("OptionPane.errorIcon"));
editPane.insertIcon(UIManager.getIcon("OptionPane.warningIcon"));
...
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Component view = jScrollPane.getViewport().getView();
BufferedImage img = new BufferedImage(view.getWidth(),
view.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D off = img.createGraphics();
off.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
off.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
RenderingHints.VALUE_INTERPOLATION_BICUBIC);
view.paint(off);
Graphics2D on = (Graphics2D)g;
on.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
on.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
RenderingHints.VALUE_INTERPOLATION_BICUBIC);
on.drawImage(img, 0, 0, getWidth(), getHeight(), null);
}
Addendum secundum: It looks like the JPanel UI delegate is not cooperating. One workaround is to extend JComponent so that you can control opacity. It's only slightly more work to manage the backgroundColor. NavBox and JScrollNavigator are also candidates for a similar treatment.
jsp.setViewportView(new JComponent() {
{
setBackground(Color.red);
setBorder(BorderFactory.createLineBorder(Color.BLACK, 16));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(getBackground());
g.fillRect(0, 0, getWidth(), getHeight());
}
#Override
public Dimension getPreferredSize() {
return new Dimension(300, 300);
}
});
I am also not sure what you mean by corruption, but I noticed that the resampled image is much nicer if you specify Image.SCALE_SMOOTH as the rescaling hint:
Image scaled = img.getScaledInstance(getWidth(), getHeight(), Image.SCALE_SMOOTH);
Maybe this is what you are looking for...
I was able to reproduce your problem and get you the result your looking for. The problem is that the drawing of the image wasn't complete by the time you were repainting again, so only portions of the image were being painted. To fix this, add this field to your JScrollNavigator class (as a lock):
/** Lock to prevent trying to repaint too many times */
private boolean blockRepaint = false;
When we repaint the component, this lock will be activated. It won't be released until we have been able to successfully paint the panel - then another paint can be executed.
The paintComponent needs to be changed to abide by the lock and use a ImageObserver when painting your navigation panel.
#Override
protected void paintComponent(final Graphics g) {
super.paintComponent(g);
if(!blockRepaint){
final Component view = (Component)jScrollPane.getViewport().getView();
BufferedImage img = new BufferedImage(view.getWidth(), view.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = img.createGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
// Paint JScrollPane view to off-screen image and then scale.
// It is this action that causes the display corruption!
view.paint(g2d);
ImageObserver io = new ImageObserver() {
#Override
public boolean imageUpdate(Image img, int infoflags, int x, int y,int width, int height) {
boolean result = true;
g.drawImage(img, 0, 0, null);
if((infoflags & ImageObserver.FRAMEBITS) == ImageObserver.FRAMEBITS){
blockRepaint = false;
result = false;
}
return result;
}
};
Image scaled = img.getScaledInstance(getWidth(), getHeight(), 0);
blockRepaint = g.drawImage(scaled, 0, 0, io);
}
}
I'm making my first simple game, that looks like Space Invaders.
I have used paint for drawing my hero on my JPanel. Now I guess if it's possible, in a simple way, to add a background image on my JPanel.
ImageIcon img = new ImageIcon(this.getClass().getResource("back.gif"));
Image image = img.getImage();
setDoubleBuffered(true);
hero = new Hero("hbarrel.gif",350,500);
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2d = (Graphics2D)g;
g2d.drawImage(hero.getImage(), hero.getX(), hero.getY(), this);
g2d.drawImage(image,0,0,this);
// Toolkit.getDefaultToolkit().sync();
g.dispose();
}
So, this is it: I tried to use my background img as hero img, and it works! but when I use the code above it only paints my hero img.... so it isn't a resource position issue.
Override paintComponent(Graphics) method and use Graphics.drawImage() to do that in your own custom component.
Well, try to paint the background image first and then the hero so that you have hero above background image