when I try to render a png image in Java Swing, it is cut off/zoomed on all sides. Here is my code:
this.setSize(500, 500);
this.setResizable(false);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
this.getGraphics().drawImage(getImage("IMAGE PATH"), 0, 0, this);
And this is my getImage function
public static Image getImage(String path) {
File file = new File(path);
try {
return ImageIO.read(file);
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
The image I want to render is 500x500, just like my frame, but it still comes out wrong. This also applies to when I use the function like this:
Image image = getImage("Image Path");
assert image != null;
JLabel picLabel = new JLabel(new ImageIcon(image));
Here is one of the images I am trying to render:
Here is the outcome:
It is kind of hard to tell from this example, but the ground should be lower and the trees higher.
Don't set the size of the frame
If your image is 500x500 then how can you expect the image size and frame size to be the same when the frame also has a title bar and borders?
Don't do custom painting`
Instead:
create a JLabel with an ImageIcon.
Add the label to the frame
invoke pack() before making the frame visible.
All the components will get the proper size.
Read the Swing tutorial on How to Use Labels for more information and examples.
Even though #camikr found a solution, I found a better one for my needs.
What I did, was I created a new JPanel and ran setPreferredSize with the dimensions of my JFrame (500x500). Then I overrided the paintComonent function to render the image using the Graphics2D class.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.util.Objects;
public class MyPanel extends JPanel {
public Image loadedImage = getImage("Image");
public LoadState() {
setPreferredSize(new Dimension(500,500));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g.create();
g2.drawImage(loadedImage, 0, 0, null);
g2.dispose();
}
}
EDIT: Fix what #Harald K suggested
Related
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 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 am trying to paint an image onto a panel, that is contained by a frame.
Let us say I have a 320 x 480 image.
When i try to create a frame with size 320x480 and add the panel into it, I encounter a problem.
In different operating systems, the JFrame of 320x480 is of different sizes due to title bar.
Thus my correct fit image in windows XP will not be properly painted in Windows8 or Ubuntu.
A grey patch is visible because the image was not properly placed.
I tried overriding paint method and using ImageIcon.
Please do offer a solution.
TIA
Code Snippet
CLASS PA CONTENTS
setPreferredSize(new Dimension(500,500));
.
.
JLabel image= new JLabel();
ImageIcon background = new ImageIcon(getClass().getClassLoader().getResource("Flower.jpg"));
image.setBounds(0, 0, 500, 500);
image.setIcon(background);
this.add(image); //where "this" is extending from JPanel
CLASS PB CONTENTS
frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
inserting(frame.getContentPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.setResizable(false);
private void inserting(Container pane)
{
cardPanel=new JPanel();
CardLayout cards=new CardLayout();
cardPanel.setLayout(cards);
PA home= new PA();
cardPanel.add(home,"homeScreen");
pane.add(cardPanel);
}
Don't call setSize at all, call pack (as VGR stated in his comment). pack will size your JFrame based on size's of component's within it, and gaps between those component's.
Now.. issue you will encounter is that your JFrame will be small at startup. So override getPreferredSize method for your JPanel to return dimensions of your image:
public void getPreferredSize() {
return new Dimension(image.getWidth(), image.getHeight());
}
Now your image will fit perfectly and your application will be fully OS independent.
And also, do not override paint method. Instead, override paintComponent.
Here is a small demo I made in cases like yours:
import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
public class Drawing {
JFrame frame = new JFrame();
public Drawing() {
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.add(new Panel());
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new Drawing();
}
});
}
class Panel extends JPanel {
BufferedImage image = null;
Panel() {
try {
image = ImageIO.read(new File("path-to-your-image"));
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, this);
}
#Override
public Dimension getPreferredSize() {
// Panel will be sizes based on dimensions of image
return new Dimension(image.getWidth(), image.getHeight());
}
}
}
It seems to be the layout problem. The most obvious solution is to wrap you image panel into another container with proper layout, so your panel will always have the same size.
I'm trying to get some images to scale for a chess program I'm writing. I tried writing up a small program just to get a feel for scaling images and I ran into a problem with the image displaying. Basically the image will only display properly if that ImageIcon (icon) is there and it is above pawn in the code. If it doesn't exist, it is below pawn in the code, or the image sources are different pawn displays as a black square. If I don't try and scale pawn then the whole thing works just fine regardless of whether icon is there or not. This whole thing just really perplexes me because the only association pawn and icon have is that they share a source image. Can anyone shed some light on this?
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import javax.swing.*;
public class resizeImg extends JFrame{
public void generateGui(){
JPanel mainPanel=new JPanel();
getContentPane().add(mainPanel);
JPanel main=new JPanel();
main.setBorder(BorderFactory.createLineBorder(new Color(0,0,0)));
main.setSize(400,400);
mainPanel.add(main);
mainPanel.setLayout(null);
ImageIcon icon=new ImageIcon(Toolkit.getDefaultToolkit().getImage("resources/pawn.jpg"));
//if you remove the above ImageIcon the image just displays as a black square
Image pawn=scale(Toolkit.getDefaultToolkit().getImage("resources/pawn.jpg"));
JLabel pawnContainer=new JLabel(new ImageIcon(pawn));
main.add(pawnContainer);
setSize(400,400);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public BufferedImage scale(Image i){
BufferedImage resized=new BufferedImage(50,50,BufferedImage.TYPE_INT_RGB);
Graphics2D g=resized.createGraphics();
g.drawImage(i,0,0,50,50,null);
g.dispose();
return resized;
}
public static void main(String[] args){
SwingUtilities.invokeLater(new Runnable(){
public void run(){
resizeImg imgObject=new resizeImg();
imgObject.generateGui();
imgObject.setVisible(true);
}
});
}
}
The original image loading code was designed to load to images over slow networks, so it uses a background thread to load the image. This means that when Toolkit.getImage returns, the image may not have actually begin loaded.
When you included the ImageIcon call, ImageIcon is using a MediaTracker to waitFor the image to become loaded. Because of the caching mechanism of Toolkit.getImage, repeated calls for the same image can use the cached image instead.
This is, also, why it's important to use an ImageObserver when painting images, but it may not help you in this case.
Instead, use ImageIO
public class Scale extends JFrame {
public void generateGui() {
JPanel main = new JPanel();
main.setBorder(BorderFactory.createLineBorder(new Color(0, 0, 0)));
main.setLayout(new BorderLayout());
try {
BufferedImage image = ImageIO.read(new File("path/to/image"));
Image pawn = scale(image);
JLabel pawnContainer = new JLabel(new ImageIcon(pawn));
main.add(pawnContainer);
} catch (IOException exp) {
exp.printStackTrace();
}
add(main);
setSize(400, 400);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
public BufferedImage scale(Image i) {
BufferedImage resized = new BufferedImage(50, 50, BufferedImage.TYPE_INT_RGB);
Graphics2D g = resized.createGraphics();
g.drawImage(i, 0, 0, 50, 50, this);
g.dispose();
return resized;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
Scale imgObject = new Scale();
imgObject.generateGui();
imgObject.setVisible(true);
}
});
}
}
first of all, this is the first week that I use swing, then sorry if my question is too obvious. Also, I need solutions that use the standard java libraries, since this is for homework and I'm not allowed to use strange libraries.
I'm using JLabel with ImageIcon to show images on a JFrame. Now I want to rotate the image on screen to arbitrary angles. I found something about Graphics2D but i don't find the way to do that.
Since solutions that I found doesn't work or I don't understand them, I'm interested in any solution to rotate the ImageIcon or the JLabel. Since I'm positioning the image doing setBounds on the JLabel, rotate the JLabel will be a better solution I think (this way I'm not forced to save the ImageIcon object too).
Thank you for your attention and sorry for my bad English.
Edit...
To show the image in screen I do the next:
JFrame frame = new JFrame("Something");
frame.setLayout(new FlowLayout()); //for example
JPanel panel = new JPanel();
panel.setLayout(null);
ImageIcon playerSprite = new ImageIcon("rute/to/file.png");
JLabel player = new JLabel(playerSprite);
panel.add(player);
player.setBounds(10,10,36,52); //for example
frame.getContentPane().add(panel);
frame.setVisible(true);
Resuming, how can I rotate this IconImage or the JLabel. I can use other method to show the image if you think that is better. If the solution is use Graphics2D, like I see, I will appreciate a solution to arrive to an object of this class an later return the rotated image to an ImageIcon, because when I try this...
ImageIcon imagePlayer = new ImageIcon("img/stand.png");
Image image = imagePlayer.getImage();
Graphics2D g = (Graphics2D)image.getGraphics();
At execution time, the answer is this...
Exception in thread "main" java.lang.UnsupportedOperationException: getGraphics() not valid for images created with createImage(producer)
2th edition...
Now I'm working with this code. The image rotates but the old unrotated image still remains on screen under the new one. Put a png image called stand.png on the same directory and you will see it.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.lang.Math;
public class Test {
public static void main(String args[]) throws Exception {
try {
JFrame frame = new JFrame("Rotation Test");
frame.setBounds(10,10,1008,756);
BufferedImage bi = ImageIO.read(new File("stand.png"));
Graphics2D g = (Graphics2D)bi.getGraphics();
g.rotate(Math.toRadians(45),26,26);
g.drawImage(bi, 0, 0, null);
JLabel player = new JLabel(new ImageIcon(bi));
frame.getContentPane().add(player);
player.setBounds(0,0,100,100);
frame.setVisible(true);
} catch (IOException ex) {
System.out.println("Exception");
}
}
}
Instead of rotating the component itself, consider rotating the content of a component. This example draws a rotated image in a JPanel.
Addendum: In the example RotatableImage.getImage() creates a BufferedImage directly in memory, but you can use ImageIO.read() to obtain an image from elsewhere. BufferedImage#createGraphics() is supported if you want to modify the image, but you probably just want to draw the unmodified image in a rotated graphics context as part of paintComponent().
Addendum: You're painting over the image with a rotated copy; instead, draw the image into a rotated graphics context:
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Test {
public static void main(String args[]) throws Exception {
JFrame frame = new JFrame("Rotation Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final BufferedImage bi = ImageIO.read(new File("img/stand.jpg"));
frame.add(new JPanel() {
#Override
public Dimension getPreferredSize() {
return new Dimension(bi.getWidth(), bi.getHeight());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.rotate(Math.PI / 4, bi.getWidth() / 2, bi.getHeight() / 2);
g2.drawImage(bi, 0, 0, null);
}
});
frame.pack();
frame.setVisible(true);
}
}
Since solutions that I found doesn't work or I don't understand them
Well, if you don't understand them, then you should post your SSCCE (http://sscce.org) demonstrating your test code. Then maybe someone will be able to explain how the code work.
I doubt you would be able to understand any new code we might post since the concepts of rotation an image or an Icon are all the same.
Since I'm positioning the image doing setBounds on the JLabel
Why are you using setBounds(). You should use a layout manager so you don't have to worry about this.
Edit:
Maybe you can use a Rotated Icon.