I have JPanel Which will load images.
Since images will not have the same width and height as the JPanel, I want to make the image resize and fit in the JPanel.
Read on this article, The Perils of Image.getScaledInstance()
Now IF you STILL prefer you can use something like,
Image scaledImage = originalImage.getScaledInstance(jPanel.getWidth(),jPanel.getHeight(),Image.SCALE_SMOOTH);
this before loading the image to your JPanel, probably like discussed in this answer.
I know this is quite old, but maybe this helps other people
use this class instead of a normal JLabel and pass an ImageIcon when using setIcon(#);
private class ImageLabel extends JLabel{
private Image _myimage;
public ImageLabel(String text){
super(text);
}
public void setIcon(Icon icon) {
super.setIcon(icon);
if (icon instanceof ImageIcon)
{
_myimage = ((ImageIcon) icon).getImage();
}
}
#Override
public void paint(Graphics g){
g.drawImage(_myimage, 0, 0, this.getWidth(), this.getHeight(), null);
}
}
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 am trying to add an Icon to the JButton
When I try to do this my Layout Manager (I use GridBagLayout) resizes the button and makes it larger by the size of the icon.
Is there a way to avoid this?
You could try JButton#setPreferedSize(...)
Or you could override the paintComponent method:
JButton testButton = new JButton() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, null);
}
};
If you want to do this with multiple buttons, it would be better to make a class for it ofcourse, something like:
class ImageButton extends JButton {
private final Image image;
public ImageButton(Image image) {
this.image = image;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
//drawing logic here
}
}
I had the same problem. Do these things:
Resize your image to fit the button with an image manipulating program.
use setMininumSize() and set the minimum size you want.
This will probably fix your problem.
I am new to making GUIs so I decided to try the the windows builder for eclipse, and while great I do have some doubts. I have been searching but I cannot seen to find a good way to add a background image to my "menu". For example I tried this:
public Menu() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(50, 50, 300, 250); //Dimensiones
contentPane = new JPanel() { //Imagen de Fondo
public void paintComponent(Graphics g) {
Image img = Toolkit.getDefaultToolkit().getImage(
Menu.class.getResource("/imgs/rotom.jpg"));
g.drawImage(img, 0, 0, this.getWidth(), this.getHeight(), this);
}
};
And adding the following classes:
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
But to no avail the window remains with its dull grey color, so far my code is just the standard one WindowsBuilder cooks for you plus 4 buttons but I doubt they're of importance here. Shouldn't the code I added override the paintComponent() method of the jPanel and draw the image in it?
The class for the menu is in a package within my project and the image is within a imgs package is within the same project as well.
Thanks a lot in advance.
A simple method, if you're not interested in resizing the background image or applying any effects is to use a JLabel...
BufferedImage bg = ImageIO.read(Menu.class.getResource("/imgs/rotom.jpg"));
JLabel label = new JLabel(new ImageIcon(bg));
setContentPane(label);
setLayout(...);
There are limitations to this approach (beyond scaling), in that the preferred size of the label will always be that of the image and never take into account it's content. This is both good and bad.
The other approach, which you seem to be using, is to use a specialised component
public class BackgroundPane extends JPanel {
private BufferedImage img;
public BackgroundPane(BufferedImage img) {
this.img = img;
}
#Override
public Dimension getPreferredSize() {
return img == null ? super.getPreferredSize() : new Dimension(img.getWidth(), img.getHeight());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(img, 0, 0, this);
}
}
You should avoid trying to perform any task in the paintComponent method which may take time to complete as paintComponent may be called often and usually in quick succession....
Getting the image to scale when the component is resized is an entire question into of it self, for some ideas, you could take a look at...
Java: maintaining aspect ratio of JPanel background image
Java: JPanel background not scaling
Quality of Image after resize very low -- Java
Reading/Loading images
Oh, and, you should avoid extending directly from top level containers, like JFrame, they reduce the reusability for your components and lock you into a single container
I try to create an Image View Program and have a problem in Java Image's zoom in and zoom out :D
I create a JPanel and using BufferedImage to display an image in my computer. After clicking a button, it should be zoom .
But the problem in here that, I overload the method paintComponent() in the JPanel to display a image as I want. After searching in the Google, I think I should use Graphic2D to deal with this problem. Follow on this post, the line
Graphics2D g = resizedImage.createGraphics();
g.drawImage(originalImage, 0, 0, newImageWidth , newImageHeight , null);
should be put in the overloaded method paintComponent(). Howerver, in my case, I want to zoom the image after clicking a button, so, how can i access to the paintComponent() to do the zoom ??
public class MiddlePanel extends JPanel {
private BufferedImage img;
private JButton jbtZoom = new JButton("Zoom");
public MiddlePanel(int width){
img = ImageIO.read(new FileInputStream(new File("C:\\Picture\\pic1.jpg")));
this.setPreferredSize(new Dimension(800,460));
}
public void paintComponent(Graphics g) {
g.drawImage(img......);
}
public void addComponentActionListener(){
jbtZoom.addActionListener(new ActionListener{
public void actionPerformed(){
//What should I do in here to zoom the image....
}
});
}
Thank for your help!
You need to change your design like so:
Store in a variable your zoom state and then your
overridden paintComponent method should look at that variable to
decide if/how much to zoom.
Your ActionListener will update the variable then call repaint() on
the panel.
I am new in Java and I am currently creating a game with graphics. I have this class that extends from JFrame. In this class, I have many JPanels that needs an image as background. As I know, to be able to paint images in the JPanel, I need to have a separate class that extends from JPanel and that class's paintComponent method will do the work. But I don't want to make separate classes for each JPanel, I have too many of them; and with the fact that I am only concerned with the background. How can I do this? is it with an anonymous inner class? How?
For better understanding I provided some code:
public GUI extends JFrame {
private JPanel x;
...
public GUI() {
x = new JPanel();
// put an image background to x
}
Why not make a single class that takes a Image??
public class ImagePane extends JPanel {
private Image image;
public ImagePane(Image image) {
this.image = image;
}
#Override
public Dimension getPreferredSize() {
return image == null ? new Dimension(0, 0) : new Dimension(image.getWidth(this), image.getHeight(this));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.drawImage(image, 0, 0, this);
g2d.dispose();
}
}
You would even provide hints about where it should be painted.
This way, you could simply create an instance when ever you needed it
Updated
The other question is, why?
You could just use a JLabel which will paint the icon for you without any additional work...
See How to use labels for more details...
This is actually a bad idea, as JLabel does NOT use it's child components when calculating it's preferred size, it only uses the size of the image and the text properties when determining it's preferred size, this can result in the component been sized incorrectly
You don't have to make another class for it? You could just do:
x = new JPanel(){
public void paintComponent(Graphics g){
super.paintComponent(g);
//draw background image
}
};
You can do this in single line:
panelInstance.add(new JLabel(new ImageIcon(ImageIO.read(new File("Image URL")))));
I hope it will work for you.