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Java -Repaint() not working when i want to call it

I wonder why the repiant() method is not working as intended. My Code:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JPanel;
public class RightPanel extends JPanel implements ActionListener{
JButton buttono;
JButton buttonu;
MyFrame frame;
ButtomPanel s;
public RightPanel(MyFrame frame){
super();
this.frame=frame;
s= new ButtomPanel(frame);
this.setPreferredSize(new Dimension((frame.getWidth()/3),frame.getHeight()));
setBackground(Color.green);
setLayout(new BorderLayout());
buttono = new JButton ("up");
buttonu = new JButton ("down");
buttono .addActionListener(this);
buttonu .addActionListener(this);
add(buttono , BorderLayout.NORTH);
add(buttonu , BorderLayout.SOUTH);
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource()==buttono) {
System.out.println("Up");
s.x=s.x+10;
s.repaint();
}
}
I want to Repaint following class:
import java.awt.Color;
import java.util.Timer;
import java.util.TimerTask;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class ButtomPanel extends JPanel {
MyFrame frame;
BufferedImage image;
boolean geklickt=false;
public static int x=0;;
public ButtomPanel(MyFrame frame) {
super();
this.frame=frame;
this.setPreferredSize(new Dimension(((frame.getWidth()/3)*2),585));
setBackground(Color.blue);
java.net.URL resource = getClass().getResource("/resources/siegel.jpg");
try {
image = ImageIO.read(resource);
} catch (IOException e) {
e.printStackTrace();
}
setVisible(true);
}
public void paint(Graphics g) {
super.paint(g);
g.drawImage(image, 150+x, 150+x, 150, 150, null);}
}
}
I want to change with the ActionListener in the RightPanel Class the x from the BottomPanel Class and then repaint it, but it doesnt work. I can raise the x, but s.repaint() does not call the paint-Method.

s is never added to anything, so it will never be painted.
this.setPreferredSize(new Dimension((frame.getWidth()/3),frame.getHeight())); is a horribly bad idea. The window should be conforming to the size of the components, not the other way round. In fact, there's never really a good reason to expose MyFrame to the components this way, it provides these components control over MyFrame which they should never have.
java.net.URL resource = getClass().getResource("/resources/siegel.jpg");
try {
image = ImageIO.read(resource);
} catch (IOException e) {
e.printStackTrace();
}
is a bad idea. The class should be throwing the exception to those using it, so that they know something has gone wrong. Doing it this way not only consumes the error in a way which is difficult to trace, but also sets you up for a NullPointerException when you call g.drawImage(image, 150+x, 150+x, 150, 150, null)
Don't override paint
public void paint(Graphics g) {
super.paint(g);
g.drawImage(image, 150+x, 150+x, 150, 150, null);
}
prefer paintComponent instead. paint is actually a very complex method. See Painting in AWT and Swing and Performing Custom Painting for more details
public static int x=0; is a bad idea for a three reasons:
static is not your friend. What happens when you have more than one instance of ButtomPanel? Generally speaking, when you use static in this way, it's a red flag telling you that your design is wrong.
public is providing uncontrolled access to the property. This is generally discouraged and you could be preferring to use setters and getters to interact with the property.
JPanel already has a x property, which could make it confusing (ie if if someone used getX instead of x). Better to rename it to something like imageX of imageXOffset.
Runnable example...
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public final class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
JFrame frame = new JFrame();
frame.add(new RightPanel());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
} catch (IOException ex) {
Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
}
}
});
}
public class RightPanel extends JPanel implements ActionListener {
JButton buttono;
JButton buttonu;
ButtomPanel s;
public RightPanel() throws IOException {
super();
s = new ButtomPanel();
setBackground(Color.green);
setLayout(new BorderLayout());
buttono = new JButton("up");
buttonu = new JButton("down");
buttono.addActionListener(this);
buttonu.addActionListener(this);
add(buttono, BorderLayout.NORTH);
add(buttonu, BorderLayout.SOUTH);
add(s);
setVisible(true);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == buttono) {
System.out.println("Up");
s.addToImageXOffset(10);
}
}
}
public class ButtomPanel extends JPanel {
private BufferedImage image;
private int imageXOffset = 0;
public ButtomPanel() throws IOException {
super();
setBackground(Color.blue);
image = ImageIO.read(getClass().getResource("/images/Heart.png"));
}
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 400);
}
public void addToImageXOffset(int delta) {
setImageXOffset(getImageXOffset() + delta);
}
public void setImageXOffset(int imageXOffset) {
this.imageXOffset = imageXOffset;
repaint();
}
public int getImageXOffset() {
return imageXOffset;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g); //To change body of generated methods, choose Tools | Templates.
g.drawImage(image, 150 + imageXOffset, 150 + imageXOffset, this);
}
}
}

Image is not being confined to a direct area

Image is not being confined to a direct area in this java code below. I want the java image to be displayed in its entirety in a 400 width by 400 height image. I tried to do that by frame.setSize(400, 400); and it is not working. My code includes drawImage which is what I was told I had to put in the code for this to work. I don't what to do next.
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.WindowConstants;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
public class SwingSandbox {
public static void main(String[] args) throws IOException {
JFrame frame = buildFrame();
final BufferedImage image = ImageIO.read(new File("/Users/johnzalubski/Desktop/c.jpg"));
JPanel pane = new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, null);
}
};
frame.add(pane);
}
private static JFrame buildFrame() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setSize(400, 400);
frame.setVisible(true);
return frame;
}
}

I reworked your Swing sandbox code a bit. Here's what I came up with.
The image is distorted because I made it fit a 400 x 400 drawing panel. You should reduce the image and maintain the aspect ratio.
Here are the changes I made.
I added the call to the SwingUtilities invokeLater method to put the Swing components on the Event Dispatch Thread.
I made the drawing panel a class, so I could set the preferred size. You set the size of the drawing panel, not the JFrame. Who cares how large or small the JFrame is?
I put the JFrame method calls in the correct order.
And here's the code.
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
public class SwingSandbox implements Runnable {
public static void main(String[] args) throws IOException {
SwingUtilities.invokeLater(new SwingSandbox());
}
private BufferedImage image;
public SwingSandbox() {
try {
image = ImageIO.read(new File("C:\\Users\\Owner\\OneDrive\\Pictures\\Saved Pictures\\StockMarketGame.png"));
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
public void run() {
JFrame frame = new JFrame("Image Display");
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
DrawingPanel panel = new DrawingPanel(image);
frame.add(panel);
frame.pack();
frame.setVisible(true);
}
public class DrawingPanel extends JPanel {
private static final long serialVersionUID = 1L;
private BufferedImage image;
public DrawingPanel(BufferedImage image) {
this.image = image;
this.setPreferredSize(new Dimension(400, 400));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, 400, 400, null);
}
}
}

You are changing how big is frame. You should use something like this: g.drawImage(image, 0, 0, 400, 400, null);
If this help you please vote me up. I’am here new and want to have some basic reputation. Thanks! 😀

How do I draw an image to a JPanel or JFrame?

How do I draw an Image to a JPanel or JFrame, I have already read oracle's tutorial on this but I can't seem to get it right. I need the image "BeachRoad.png" to be displayed on a specific set of coordinates. Here is what I have so far.
public class Level1 extends JFrame implements ActionListener {
static JLayeredPane EverythingButPlayer;
static Level1 l1;
public Level1() {
EverythingButPlayer = new JLayeredPane();
BufferedImage img = null;
try {
img = ImageIO.read(new File("BeachRoad.png"));
} catch (IOException e) {
}
Graphics g = img.getGraphics();
g.drawImage(img,0, 0, EverythingButPlayer);
this.add(EverythingButPlayer);
}
And in the Main(),
l1 = new Level1();
l1.setTitle("poop");
l1.setSize(1920, 1080);
l1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
l1.setVisible(true);
Thanks in advance!

Try this:
package com.sandbox;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.WindowConstants;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
public class SwingSandbox {
public static void main(String[] args) throws IOException {
JFrame frame = buildFrame();
final BufferedImage image = ImageIO.read(new File("C:\\Projects\\MavenSandbox\\src\\main\\resources\\img.jpg"));
JPanel pane = new JPanel() {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, null);
}
};
frame.add(pane);
}
private static JFrame buildFrame() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setSize(200, 200);
frame.setVisible(true);
return frame;
}
}

There are a lot of methods, but I always override the paint(Graphics g) of a JComponent and use g.drawImage(...)
edit: I was making a sample, but Daniel Kaplan did it perfectly, look at his answer :)

JPanel with a background image which has some part transparent

My image is like a frame which is transparent in the middle. I want to make it as background image of a JPanel. I have done this but for the transparent part of image, white color is coming. I want to remove this white color so that the components below this Jpanel become visible.
My code for custom JPanel is
public class JPanelWithBackground extends JPanel {
private static final long serialVersionUID = 1L;
Image imageOrg = null;
Image image = null;
{
addComponentListener(new ComponentAdapter() {
public void componentResized(ComponentEvent e) {
int w = JPanelWithBackground.this.getWidth();
int h = JPanelWithBackground.this.getHeight();
image = w>0&&h>0?imageOrg.getScaledInstance(w,h,
java.awt.Image.SCALE_SMOOTH):imageOrg;
JPanelWithBackground.this.repaint();
});
}
public JPanelWithBackground(Image image2) {
imageOrg=image2;
image=image2;
setOpaque(false);
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
if (image!=null)
g.drawImage(image, 0, 0, null);
}
}

I don't have any particular problem with your code. The problem is probably that your image is not transparent as you expect.
Here is an example that seems to work perfectly (I only took the liberty to fix minor issues in your code):
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.net.MalformedURLException;
import java.net.URL;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class JPanelWithBackground extends JPanel {
private static final long serialVersionUID = 1L;
Image imageOrg = null;
public JPanelWithBackground(Image image2) {
imageOrg = image2;
setOpaque(false);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(imageOrg.getWidth(this), imageOrg.getHeight(this));
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
if (imageOrg != null) {
System.err.println("painting");
g.drawImage(imageOrg, 0, 0, getWidth(), getHeight(), this);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
try {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanelWithBackground panel = new JPanelWithBackground(new ImageIcon(new URL(
"http://www.lemondedemario.fr/images/dossier/bowser/bowser.png")).getImage());
JPanel greenPanel = new JPanel(new BorderLayout());
greenPanel.setBackground(Color.GREEN);
greenPanel.add(panel);
frame.add(greenPanel);
frame.pack();
frame.setVisible(true);
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
}

Java Swing: Transparent PNG permanently captures original background

I have the following code:
import javax.swing.JWindow;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
public class sutff extends JWindow
{
//Get transparent image that will be use as splash screen image.
Image bi=Toolkit.getDefaultToolkit().getImage("window.png");
ImageIcon ii=new ImageIcon(bi);
public sutff()
{
try
{
setSize(ii.getIconWidth(),ii.getIconHeight());
setLocationRelativeTo(null);
show();
//Thread.sleep(10000);
//dispose();
//JOptionPane.showMessageDialog(null,"This program will exit !!!","<>",JOptionPane.INFORMATION_MESSAGE);
}
catch(Exception exception)
{
exception.printStackTrace();
}
}
//Paint transparent image onto JWindow
public void paint(Graphics g)
{
g.drawImage(bi,0,0,this);
}
public static void main(String[]args)
{
sutff tss=new sutff();
}
}
The purpose is to create a window that is translucent and resembles Windows Aero-style glass. I have the following transparent png that I am using:
http://i.imgur.com/5UNGbsr.png
The problem is that since its transparent, its suppose to show the things behind the window, right? That's what it does when first executed, except whatever window is behind this "transparent window" when it first starts up, the program somehow creates an "image" of that and permanently attaches it with the window. So even if I minimize the windows behind this "transparent window," the image of the first background window remains.
Here is a screenshot:
When I took this screen shot, I had already minimized the command prompt and the IDE which can be seen in the background, yet it still remains in the background of the window.
What am I doing wrong?

Don't override the paint() method of a top level container, especially when you don't invoke super.paint(). This will cause painting problems. If you ever do need to do custom painting then you should override the paintComponent() method of JPanel (or JComponent) and then add the panel to the window/frame. Read the Swing tutorial on Custom Painting. This advice is given daily, I don't know why people still try to override paint()???
However this is only one of your problems. The better solution is to add your image to a JLabel and then add the label to the window. You will also need to make the window background transparent:
import javax.swing.*;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane;
import java.awt.*;
import java.awt.Image;
import java.awt.Toolkit;
public class Stuff extends JWindow
{
//Get transparent image that will be use as splash screen image.
Image bi=Toolkit.getDefaultToolkit().getImage("transparent.png");
ImageIcon ii=new ImageIcon(bi);
public Stuff()
{
try
{
setBackground( new Color(0, 0, 0, 0) );
setSize(ii.getIconWidth(),ii.getIconHeight());
setLocationRelativeTo(null);
JLabel label = new JLabel(ii);
add(label);
show();
//Thread.sleep(10000);
//dispose();
//JOptionPane.showMessageDialog(null,"This program will exit !!!","<>",JOptionPane.INFORMATION_MESSAGE);
}
catch(Exception exception)
{
exception.printStackTrace();
}
}
/*
//Paint transparent image onto JWindow
public void paint(Graphics g)
{
super.paint(g);
g.drawImage(bi,0,0,this);
}
*/
public static void main(String[]args)
{
Stuff tss=new Stuff();
}
}

The problem is, you window is actually transparent. Java still thinks that the Window opaque and therefore won't update the graphics in such away as to show what's actually behind.
Creating a transparent window is relatively simple in Java since Java 1.6.10 (I think)
The following is a very simple example, using a semi transparent paint effect that will allow what ever falls below the window to continue to be painted correctly.
import com.sun.awt.AWTUtilities;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Shape;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.RoundRectangle2D;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TransaprentBlur {
public static void main(String[] args) {
new TransaprentBlur();
}
public TransaprentBlur() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setUndecorated(true);
frame.setBackground(new Color(0, 0, 0, 0));
// Java 6...
// AWTUtilities.setWindowOpaque(frame, true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.setSize(400, 400);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setOpaque(false);
addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
if (e.getClickCount() == 2) {
System.exit(0);
}
}
});
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Shape shape = new RoundRectangle2D.Float(0, 0, getWidth() - 1, getHeight() - 1, 20, 20);
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(new Color(225, 225, 225, 128));
g2d.fill(shape);
g2d.setColor(Color.GRAY);
g2d.draw(shape);
g2d.dispose();
}
}
}
Update with image example
Screen shoots showing windows been moved behind the window...
Basically, all you need to do, is place you image rendering code with in the paintComponent method of TestPane
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TransaprentBlur {
public static void main(String[] args) {
new TransaprentBlur();
}
public TransaprentBlur() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setUndecorated(true);
frame.setBackground(new Color(0, 0, 0, 0));
// Java 6...
// AWTUtilities.setWindowOpaque(frame, true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.setSize(400, 400);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private BufferedImage image;
public TestPane() {
try {
image = ImageIO.read(getClass().getResource("/5UNGbsr.png"));
} catch (IOException ex) {
}
setOpaque(false);
addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
if (e.getClickCount() == 2) {
System.exit(0);
}
}
});
}
#Override
public Dimension getPreferredSize() {
return image == null ? super.getPreferredSize() : new Dimension(image.getWidth(), image.getHeight());
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (image != null) {
Graphics2D g2d = (Graphics2D) g.create();
int x = (getWidth() - image.getWidth()) / 2;
int y = (getHeight() - image.getHeight()) / 2;
g2d.drawImage(image, x, y, this);
g2d.dispose();
}
}
}
}