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image to show up when I press the button in java swing (error in frame.add( ) )

Hello first of all when I run the program a button appear , when I press the button the image will go from top to down.
I try the code when the image go from top to down , it work very well
BUT when I put all the codes together there is an error in ( frame.add(new AnimationPane() ); )
Question : How to add AnimationPane() to the frame ???
because this is my problem.
The idea that I want to make two scenes , the first one have a button to make go to the second scene which will have an image (it must be pushed from top until reach down ).
/*
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*/
package maincontentpaneswitching;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class MainContentPaneSwitching {
private static class ChangeContentPaneListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
// I want to put the image here
JPanel newFrameContents = new JPanel(); //Uses FlowLayout by default.
newFrameContents.add(new JLabel("You have successfully changed the content pane of the frame!", JLabel.CENTER));
/*We assume that the source is a JButton and that the Window is of type JFrame, hence
the following utility method call is possible without letting any errors appear:*/
JFrame frame = (JFrame) SwingUtilities.getWindowAncestor((JButton) e.getSource());
frame.setSize(600, 300);
frame.setContentPane(newFrameContents); //Change the content pane of the frame.
frame.revalidate(); //Notify the frame that the component hierarchy has changed.
frame.add(new AnimationPane() );
frame.pack(); //Resize the frame as necessary in order to fit as many contents as possible in the screen.
frame.setLocationRelativeTo(null); //Place the frame in the center of the screen. As you can tell, this needs its size to calculate the location, so we made sure in the previous line of code that it is set.
frame.repaint(); //Repaint frame with all its contents.
}
}
public class AnimationPane extends JPanel {
private BufferedImage boat;
private int yPos = 0;
private int direction = 1;
public AnimationPane() {
try {
boat = ImageIO.read(new URL("https://i.stack.imgur.com/memI0.png"));
Timer timer = new Timer(50, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
yPos += direction;
if (yPos + boat.getHeight() > getHeight()) {
yPos = getHeight() - boat.getHeight();
direction *= +1;
} else if (yPos < 0) {
yPos = 0;
direction *= +1;
}
repaint();
}
});
timer.setRepeats(true);
timer.setCoalesce(true);
timer.start();
} catch (IOException ex) {
ex.printStackTrace();
}
}
#Override
public Dimension getPreferredSize() {
return boat == null ? super.getPreferredSize() : new Dimension(boat.getHeight()*2 , boat.getWidth() *2);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
int x = getWidth() - boat.getWidth();
g.drawImage(boat, x, yPos, this);
}
}
private static class MainRunnable implements Runnable {
#Override
public void run() {
JButton changeContentPaneButton = new JButton("Click to go to the next image!");
changeContentPaneButton.addActionListener(new ChangeContentPaneListener());
JPanel frameContents = new JPanel(); //Uses FlowLayout by default.
frameContents.add(changeContentPaneButton);
JFrame frame = new JFrame("My application");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //Tells the frame that when the user closes it, it must terminate the application.
frame.setContentPane(frameContents); //Add contents to the frame.
frame.pack(); //Resize the frame as necessary in order to fit as many contents as possible in the screen.
frame.setLocationRelativeTo(null); //Place the frame in the center of the screen. As you can tell, this needs its size to calculate the location, so we made sure in the previous line of code that it is set.
frame.setVisible(true);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new MainRunnable()); //Swing code must always be used in the Event Dispatch Thread.
}
}

Introduction
As I said in my comment, I couldn't get the image animation to work properly. At least this code would give you a solid foundation to start with.
Here's the GUI I came up with.
Here's the GUI after you left-click on the button.
If you're going to add comments to your code, put the comments on separate lines from the code. Not everyone has a large monitor and can read 200+ character lines of code.
Explanation
Oracle has a rad tutorial, Creating a GUI With Swing. Skip the Netbeans section.
When I create a Swing GUI, I use the model/view/controller (MVC) pattern. This pattern allows me to separate my concerns and focus on one part of the application at a time.
In Swing, the MVC pattern means:
The view reads information from the model
The view may not update the model
The controller updates the model and repaints/revalidates the view.
There's usually not one controller to "rule them all". Each listener controls its portion of the model and the view.
When I put together an application, I code one tiny tiny piece of it, then run tests. I probably ran two to three dozen tests, and this was mostly coded by you.
Model
I created a BoatImage class to read the boat image. It's a separate class, so I can read the image before I start to construct the GUI.
View
I created a JFrame. I created a main JPanel with a CardLayout.
I use a CardLayout to layout the button JPanel and the image JPanel. This way, the JFrame is not constantly changing size.
I create the JFrame and JPanels as separate methods/classes. This makes it much easier for people, including yourself, to read and understand the view code.
Controller
I coded the ChangeContentPaneListener to change from the button JPanel to the image JPanel. This is where you would put your image animation code.
Code
Here's the complete runnable code. I made all the additional classes inner classes so I could post this code as one block.
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
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.net.MalformedURLException;
import java.net.URL;
import javax.imageio.ImageIO;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class MainContentPaneSwitching implements Runnable {
public static void main(String[] args) {
// Swing code must always be used in the Event Dispatch Thread.
SwingUtilities.invokeLater(new MainContentPaneSwitching());
}
private AnimationPane animationPane;
private BoatImage boatImage;
private CardLayout cardLayout;
private JPanel mainPanel;
public MainContentPaneSwitching() {
this.boatImage = new BoatImage();
}
#Override
public void run() {
JFrame frame = new JFrame("My application");
// Tells the frame that when the user closes it, it
// must terminate the application.
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.mainPanel = createMainPanel();
frame.add(mainPanel, BorderLayout.CENTER);
// Resize the frame as necessary in order to fit as many contents
// as possible in the screen.
frame.pack();
// Place the frame in the center of the screen. As you can tell, this
// needs its size to calculate the location, so we made sure in the
// previous line of code that it is set.
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private JPanel createMainPanel() {
cardLayout = new CardLayout();
JPanel panel = new JPanel(cardLayout);
panel.add(createButtonPanel(), "button");
animationPane = new AnimationPane(boatImage);
panel.add(animationPane, "image");
return panel;
}
private JPanel createButtonPanel() {
JPanel panel = new JPanel(new FlowLayout());
panel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
JButton changeContentPaneButton = new JButton(
"Click to go to the next image!");
changeContentPaneButton.addActionListener(
new ChangeContentPaneListener(this, boatImage));
panel.add(changeContentPaneButton);
return panel;
}
public JPanel getAnimationPane() {
return animationPane;
}
public void repaint() {
animationPane.repaint();
}
public class AnimationPane extends JPanel {
private static final long serialVersionUID = 1L;
private BoatImage boat;
public AnimationPane(BoatImage boat) {
this.boat = boat;
BufferedImage image = boat.getBoat();
this.setPreferredSize(new Dimension(image.getWidth(),
image.getHeight()));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
BufferedImage image = boat.getBoat();
int x = getWidth() - image.getWidth();
g.drawImage(image, x, boat.getyPos(), this);
}
}
private class ChangeContentPaneListener implements ActionListener {
private int direction, yPos;
private final MainContentPaneSwitching view;
private final BoatImage model;
public ChangeContentPaneListener(MainContentPaneSwitching view,
BoatImage model) {
this.view = view;
this.model = model;
this.direction = 1;
this.yPos = 0;
}
#Override
public void actionPerformed(ActionEvent e) {
cardLayout.show(mainPanel, "image");
}
}
public class BoatImage {
private int yPos;
private BufferedImage boat;
public BoatImage() {
try {
URL url = new URL("https://i.stack.imgur.com/memI0.png");
boat = ImageIO.read(url); // boat.jpg
} catch (MalformedURLException e) {
e.printStackTrace();
boat = null;
} catch (IOException e) {
e.printStackTrace();
boat = null;
}
this.yPos = 0;
}
public BufferedImage getBoat() {
return boat;
}
public void setyPos(int yPos) {
this.yPos = yPos;
}
public int getyPos() {
return yPos;
}
}
}

paint() can't draw gif but png works fine?

I'm using a JLabel in an attempt to draw an animated gif image onto it. I can use the constructor new JLabel(new ImageIcon(FML.class.getResource("giphy.gif"))); and that will work just fine however when I go override the paint method it just doesn't seem to want to draw it, at all. The image isn't still, it's not there! I should mention that both methods shown below work perfectly fine with a PNG but not a GIF. Am I missing something or is this a java bug?
(Using java 1.8)
Edit: I've been looking around and it seems that I'm not completely off point on what I need to be doing but I'm missing something. I've seen many posts Like this one but that doesn't seem to be working in this case.
I should note that there's literally nothing else going on in the class, it's a simple JPanel.
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.GridBagLayout;
import java.awt.Image;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class FML {
public static void main(String[] args) {
new FML();
}
public FML() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
} catch (UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(new FlowLayout());
frame.getContentPane().add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private ImageIcon animatedGif;
public TestPane() {
setLayout(new GridBagLayout());
JButton btn = new JButton(new ImageIcon(FML.class.getResource("FmDxW.png")));
btn.setSize(50, 50);
btn.setRolloverEnabled(true);
animatedGif = new ImageIcon(FML.class.getResource("giphy.gif"));
btn.setRolloverIcon(animatedGif);
add(btn);
btn.addMouseListener(new MouseAdapter() {
#Override
public void mouseEntered(MouseEvent e) {
animatedGif.getImage().flush();
}
});
//I need this
final ImageIcon image = new ImageIcon(FML.class.getResource("giphy.gif"));
//To render over this
final ImageIcon image2 = new ImageIcon(FML.class.getResource("fmDxW.png"));
//I'm not understanding why I can add the gif into the constructor but the paint method fails.
JLabel label = new JLabel(image) {
#Override
public void paint(Graphics g) {
super.paint(g);
g.drawImage(image2.getImage(), 64, 64, this);
}
};
//setSize because I want to be 100% sure that it's loading the correct size.
//Removing it doesn't affect the problem at hand.
label.setSize(64, 64);
add(label);
}
}
}

g.drawImage(image2.getImage(), 64, 64, this);
Assuming the size of your image is 64, why are you trying to draw the second image outside the bounds of the label? When I change the location to (0, 0) the gif paints fine for me (but I'm not using an animated gif).
both methods shown below work perfectly fine with a PNG but not a GIF.
I don't see how for the reason I gave above. In any case, did you try it with a normal gif?
This is a reason why you should not be trying to manage the painting yourself since now you need to worry about location and hardcoding a location is not a good practice. Let your layout manager do this for you.
Again, why are you doing this. Why are you trying to override paint method to draw a second image?
Instead you should be doing something like:
Drawing both images in the paintComponent() method
Use a panel with an OverlayLayout, Then you can stack the two labels on top of one another.
You can even set the layout manager of the layout to something like a GridBagLayout and then when you add a JLabel to the label it will automatically be centered.
//setSize because I want to be 100% sure that it's loading the correct size.
You said you know how layout managers work. Well if you do then you know that this statement will do nothing since the layout manager will override any value you set, so using code like this wrong and shows a basic lack of understanding and should not be included in an MCVE since the point of the MCVE` is to simplify the problem as much as possible.

JPanel Animated Background

This is a really general question, but how should I add an animated background for a JPanel. I want the background to be behind all the panel's components and graphics. Right now, I have two separate classes (one for the main panel and the other for the background). The background class uses repaint() to animate a grid moving across the screen. I've tried to make the main panel background transparent, but that hasn't gotten me anywhere.
Even more info:
My main panel is part of a CardLayout and it has many different classes in it. So when I'm adding my main panel to my main frame, I'm doing frame.getContentPane().add(cards, BorderLayout.CENTER)
cards is a JPanel which acts as a container for the mainpanel and all the panels inside main panel.
Can anybody help me out in getting a panel animated background?

You can use Toolkit.getImage() to load animated image and then draw the image in container's paintComponent. Make sure the ImageObserver is set (not null) in order to update animation frames properly. For details how image is loaded, observed and updated see How Images are Loaded appendix in Java AWT Reference.
Here is a simple example:
import java.awt.*;
import javax.swing.*;
import java.net.URL;
class AnimatedPanelDemo {
static class ImagePanel extends JPanel {
private Image image;
ImagePanel(Image image) {
this.image = image;
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image,0,0,getWidth(),getHeight(),this);
}
}
private static void createAndShowUI() {
try {
JFrame frame = new JFrame("Image");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
Image image = Toolkit.getDefaultToolkit().getImage(new URL(
"http://duke.kenai.com/iconSized/duke.running.gif"));
ImagePanel imagePanel = new ImagePanel(image);
imagePanel.add(new JLabel("Some label"));
frame.add(imagePanel);
frame.setSize(100, 100);
frame.setVisible(true);
}
catch (Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}

Well, this is my first answer on stackoverflow.
Will try to help with my learning curve with this complex AWT and Swift API.
Below there's the contructor that extends JFrame
package xpto;
import java.awt.Dimension;
import java.awt.GraphicsConfiguration;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.awt.event.WindowStateListener;
import java.awt.image.ImageObserver;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import sun.java2d.SunGraphicsEnvironment;
import java.awt.Graphics;
import java.awt.Graphics2D;
public class FrameLuckyRaffle extends JFrame {
/**
*
*/
private JLabel backgroundLabel;
private ImageIcon imageIcon;
private Image bgImage;
/**
* Constructor of this frame.
*/
public FrameLuckyRaffle(String background, final String dbname) {
try {
setTitle("Lucky Raffle of "+ dbname);
GraphicsConfiguration config = this.getGraphicsConfiguration();
Rectangle usableBounds = SunGraphicsEnvironment.
getUsableBounds(config.getDevice());
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
setBounds(100, 100, (int)(usableBounds.getWidth()*0.8),
(int)(usableBounds.getHeight()*0.8));
setMinimumSize(new Dimension(1024, 700));
setResizable(true);
setDefaultLookAndFeelDecorated(true);
backgroundLabel = new JLabel() {
public void paintComponent(Graphics g) {
// alternative --> g.drawImage(bgImage, 0, 0, null);
// I prefer to control the new ImageObserver parameter as bellow
g.drawImage(bgImage, 0, 0, new ImageObserver() {
#Override
public boolean imageUpdate(Image img, int infoflags,
int x, int y, int width, int height) {
img.getScaledInstance(getWidth(),getHeight(),
Image.SCALE_FAST);
return true;
}
});
// this is used to have easier control on
// image manipulation on my application
Graphics2D g2d = (Graphics2D)g;
super.paintComponent(g2d);
revalidate();
repaint();
}
};
backgroundLabel.setBounds(0, 0, 0, 0);
// this is necessary if you want more child
// components to be visible on the JFrame afterwards
backgroundLabel.setOpaque(false);
setContentPane(backgroundLabel);
addWindowListener(new WindowListener() {
#Override
public void windowOpened(WindowEvent e) {
// Set Frame Background
imageIcon = new ImageIcon(Toolkit.getDefaultToolkit().
createImage(FrameBusinessPure.class.getResource(background)));
bgImage = imageIcon.getImage().
getScaledInstance(getWidth(),getHeight(), Image.SCALE_FAST);
}
// Even after closing the window, JVM didn't Garbage Collected the instanced
// objects, for some reason. Forcing the objects to null helped on that.
#Override
public void windowClosed(WindowEvent e) {
backgroundLabel = null;
imageIcon = null;
bgImage = null;
System.gc();
}
});
addWindowStateListener(new WindowStateListener() {
#Override
public void windowStateChanged(WindowEvent e) {
// if you flush the object on runtime you will surpass the
// memory leak on using GIFs and most complex graphics
bgImage.flush();
bgImage = imageIcon.getImage().
getScaledInstance(getWidth(),getHeight(), Image.SCALE_FAST);
}
});
addMouseMotionListener(new MouseMotionListener() {
#Override
public void mouseDragged(MouseEvent e) {
// if you flush the object on runtime you will surpass the
// memory leak on using GIFs and most complex graphics
bgImage.flush();
bgImage = imageIcon.getImage().
getScaledInstance(getWidth(),getHeight(), Image.SCALE_FAST);
});
}catch (Exception e) {
e.printStackTrace();
}
}
}
Feel free to learn more on below link
https://www.oracle.com/java/technologies/painting.html

MouseWheel Flicker, More about the why

A few days ago I posted a question about a program that caused text on screen to change color when the mousewheel was scrolled. It was unfortunately a badly put together question with too much code posted to be particularly useful.
I had several responses, one of which was from the user trashdog who posted something that fixed the problem (which can be found at the bottom of this page here: Window going blank during MouseWheelMotion event) , however having read the class descriptions of all the things I didn't know about in the program he posted and gone through its execution I don't understand why his achieves a different effect from mine.
His seems to log every mouse wheel movement where as mine only does the initial movement. Also several people commented that they couldn't replicate the effect of my program probably because it was so big.
Below is an extremely simplified version which still elicits the same effect (I hope).
Question: What is the fundamental difference between the two programs that fixes the screen going blank when the mouse wheel events are being processed?
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.event.MouseWheelEvent;
import java.awt.event.MouseWheelListener;
import java.util.LinkedList;
import javax.swing.JFrame;
public class WheelPrinter implements MouseWheelListener, Runnable {
JFrame frame;
LinkedList colorList;
int colorCount;
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
WheelPrinter w = new WheelPrinter();
w.run();
}
public WheelPrinter() {
frame = new JFrame();
frame.setSize(500, 500);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.addMouseWheelListener(this);
frame.setVisible(true);
frame.setBackground(Color.WHITE);
colorList = new LinkedList();
colorList.add(Color.BLACK);
colorList.add(Color.BLUE);
colorList.add(Color.YELLOW);
colorList.add(Color.GREEN);
colorList.add(Color.PINK);
}
#Override
public void mouseWheelMoved(MouseWheelEvent e) {
colorChange();
}
#Override
public void run() {
while(true) {
draw(frame.getGraphics());
try {
Thread.sleep(20);
} catch (Exception ex) {
}
}
}
public void draw(Graphics g) {
g.setColor(frame.getBackground());
g.fillRect(0,0,frame.getWidth(),frame.getHeight());
g.setFont(new Font("sansserif", Font.BOLD, 32));
g.setColor(frame.getForeground());
g.drawString("yes", 50, 50);
}
public void colorChange() {
colorCount++;
if (colorCount > 4) {
colorCount = 0;
}
frame.setForeground((Color) colorList.get(colorCount));
}
}
(Try spinning your mouse wheel really hard if you try running my code and it will become even more obvious)

while(true) { is endless loop, without break; f.e.
use Swing Timer instead of Runnable#Thread delayed by Thread.Sleep()
paint to the JPanel or JComponent, not directly to the JFrame
all painting to the Swing JComponent should be done in paintComponent()
more in the 2D Graphics tutorial
edit
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseWheelEvent;
import java.util.LinkedList;
import java.util.Queue;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
/**
* based on example by #trashgod
*
* #see http://stackoverflow.com/a/10970892/230513
*/
public class ColorWheel extends JPanel {
private static final int N = 32;
private static final long serialVersionUID = 1L;
private final Queue<Color> clut = new LinkedList<Color>();
private final JLabel label = new JLabel();
public ColorWheel() {
for (int i = 0; i < N; i++) {
clut.add(Color.getHSBColor((float) i / N, 1, 1));
}
//clut.add(Color.BLACK);
//clut.add(Color.BLUE);
//clut.add(Color.YELLOW);
//clut.add(Color.GREEN);
//clut.add(Color.PINK);
label.setFont(label.getFont().deriveFont(36f));
label.setForeground(clut.peek());
label.setText("#see http://stackoverflow.com/a/10970892/230513");
setBackground(Color.white);
add(label);
label.addMouseWheelListener(new MouseAdapter() {
#Override
public void mouseWheelMoved(MouseWheelEvent e) {
label.setForeground(clut.peek());
clut.add(clut.remove());
}
});
}
#Override
public Dimension getPreferredSize() {
int w = SwingUtilities.computeStringWidth(label.getFontMetrics(
label.getFont()), label.getText());
return new Dimension(w + 20, 80);
}
private void display() {
JFrame f = new JFrame("ColorWheel");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(this);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new ColorWheel().display();
}
});
}
}

The fundamental difference is that you are trying to interact with the Graphics object from the wrong thread and without knowing anything about the state the Graphics object is in at the time.
The generally correct way to interact with a Graphics object in Swing is by making a custom component which overrides the paintComponent(Graphics) method. You do your drawing while inside that method.
Your colorChange() method can tell your component to re-draw itself by calling repaint(), which will eventually lead to a call to paintComponent(Graphics) on the correct thread at the correct time.
See tutorial here

Drawing between 2 images in 1 JPanel

I want to draw the lines between 2 JScrollPanes (first scroll pane on the left side, second on the right). These JScrollPanes contain images. I want to draw lines between these 2 images (use some layers, use some trick etc.). I tried do it different ways, but i failed. Is it possible? (if not, i will have to make 2 images in one JScrollPane and it won't be nice).
EDIT
I want to draw between 2 images - throught components - get some points from images and draw lines between them. I apologize for poorly formulated question.

In order to accomplish this, I believe you'll need to make use of the Glass Pane. The Glass Pane sits on top of everything in the JRootPane and fills the entire view. This particular position allows two distinct capabilities:
Intercepting mouse and keyboard events
Drawing over the entire user interface
I believe your question is addressed by the second capability. The following is an example implementation, which you can later tailor to meet your own needs. Note that I've left out a lot of detail with regard to Glass Pane that you'll need to research on your own.
CODE
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.KeyAdapter;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class GlassPaneDemo {
private static BufferedImage bi;
public static void main(String[] args){
try {
loadImages();
SwingUtilities.invokeLater(new Runnable(){
#Override
public void run() {
createAndShowGUI();
}
});
} catch (IOException e) {
// handle exception
}
}
private static void loadImages() throws IOException{
bi = ImageIO.read(new File("src/resources/person.png"));
}
private static void createAndShowGUI(){
final JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setGlassPane(new CustomGlassPane());
frame.getContentPane().add(getButtonPanel());
frame.pack();
frame.setLocationRelativeTo(null);
frame.getGlassPane().setVisible(true);
frame.setVisible(true);
}
private static final JPanel getButtonPanel(){
#SuppressWarnings("serial")
final JPanel panel = new JPanel(){
#Override
protected void paintComponent(Graphics g){
Graphics gCopy = g.create();
gCopy.setColor(Color.BLUE.darker());
gCopy.fillRect(0, 0, getWidth(), getHeight());
gCopy.dispose();
}
};
final JLabel labelOne = new JLabel();
labelOne.setIcon(new ImageIcon(bi));
final JLabel labelTwo = new JLabel();
labelTwo.setIcon(new ImageIcon(bi));
panel.add(labelOne);
panel.add(labelTwo);
return panel;
}
#SuppressWarnings("serial")
private static class CustomGlassPane extends JComponent{
private Point p1;
private Point p2;
private boolean lineDrawn;
public CustomGlassPane(){
addMouseListener(new MouseAdapter(){
#Override
public void mouseClicked(MouseEvent e){
if(p1 == null || lineDrawn){
if(lineDrawn){
p1 = null;
p2 = null;
lineDrawn = false;
}
p1 = e.getPoint();
}else{
p2 = e.getPoint();
repaint(); // not optimal
lineDrawn = true;
}
}
});
// Block all other input events
addMouseMotionListener(new MouseMotionAdapter(){});
addKeyListener(new KeyAdapter(){});
addComponentListener(new ComponentAdapter(){
#Override
public void componentShown(ComponentEvent e){
requestFocusInWindow();
}
});
setFocusTraversalKeysEnabled(false);
}
#Override
protected void paintComponent(Graphics g){
if(p1 != null && p2 != null){
Graphics2D g2 = (Graphics2D) g.create();
g2.setRenderingHint(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(Color.RED);
g2.drawLine((int)p1.getX(), (int)p1.getY(), (int)p2.getX(), (int)p2.getY());
g2.dispose();
}
}
}
}
OUTPUT
EXPLANATION
In this example, I clicked two arbitrary points within each JLabel, and then drew a connecting line.

This should be very possible. You will need to create a custom component that is aware of both vertical ScrollBars. It should add itself as an AdjustmentListener to each scroll bar in order to detect changes and repaint the lines between the two.
See:
addAdjustmentListener method in the API

You can use this
http://java-sl.com/connector.html
as an example of such code.