We Keep Coding

paintComponent not called when I scroll both Horizontal and Vertical scrollbars in a JScrollPane

I am having trouble with Swing and the JScrollPane.
I am having a strange behaviour.
I extended JScrollPane. I display an image in it and draw rectangles over it to define areas.
With a big image, I have an Horizontal and a Vertical scrollbars.
I - ok - When I move one scrollbar or the other I see my image move too as it should.
II - not ok - When I move one scrollbar an leave it in between max and min position, then when I move my second scrollbar my image disappears.
With some debug prints, I found out that paintComponent, is not called when in case II.
I would like to know why it is not calling paintComponent and how I can fix it.
Here below is my class:
package GUI;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Point;
import javax.swing.JScrollPane;
public class DrawingPanel extends JScrollPane {
private static final long serialVersionUID = 1L;
private static final Color DRAWING_COLOR = new Color(255, 100, 200);
private static final Color FINAL_DRAWING_COLOR = Color.red;
private static final double ZOOMING_STEP = 1.1;
private Image sImg;
private Point startPt;
private Point endPt;
private Point currentPt;
private int prefW;
private int prefH;
private double zoomFactor = 1;
private boolean zoomer = false;
private boolean loaded = false;
public DrawingPanel() {
setFocusable(true);
setFocusTraversalKeysEnabled(false);
}
public void loadImage(Image img) {
sImg = img;
prefW = sImg.getWidth(null);
prefH = sImg.getHeight(null);
zoomFactor = getSize().getWidth() / prefW;
zoomer = true;
loaded = true;
repaint();
revalidate();
}
int countPaint = 0;
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("paintComponent " + countPaint);
if (loaded) {
int zoomWidth = (int) (prefW * zoomFactor);
int zoomHeight = (int) (prefH * zoomFactor);
if (zoomer) {
((Graphics2D) g).scale(zoomFactor, zoomFactor);
setSize(zoomWidth, zoomHeight);
zoomer = false;
}
g.drawImage(sImg, 0, 0, zoomWidth, zoomHeight, null);
drawRectangle(g);
}
g.dispose();
countPaint++;
}
#Override
public Dimension getPreferredSize() {
return loaded ?
this.getSize() :
new Dimension((int) (prefW*zoomFactor), (int) (prefH*zoomFactor));
}
private void drawRectangle(Graphics g) {
Point secondPoint = (currentPt != null) ? currentPt : endPt;
Color color = (currentPt != null) ? DRAWING_COLOR : FINAL_DRAWING_COLOR;
if (startPt!=null && secondPoint!=null) {
int x = Math.min(startPt.x, secondPoint.x);
int y = Math.min(startPt.y, secondPoint.y);
int rectangleWidth = Math.abs(startPt.x - secondPoint.x);
int rectangleHeight = Math.abs(startPt.y - secondPoint.y);
g.setColor(color);
g.drawRect(x, y, rectangleWidth, rectangleHeight);
}
}
public void deleteRectangle(){
startPt = null;
endPt = null;
}
public void increaseZoom(Point p) {
double oldZoom = zoomFactor;
zoomFactor *= ZOOMING_STEP;
repositonPointAfterZoom(oldZoom, zoomFactor);
}
public void decreaseZoom(Point p) {
double oldZoom = zoomFactor;
zoomFactor /= ZOOMING_STEP;
repositonPointAfterZoom(oldZoom, zoomFactor);
}
public void repositonPointAfterZoom(double oldZoom, double newZoom) {
double evolution = newZoom/oldZoom;
if (startPt!=null) {
startPt.setLocation(startPt.x * evolution, startPt.y * evolution);
}
if (endPt!=null) {
endPt.setLocation(endPt.x * evolution, endPt.y * evolution);
}
repaint();
}
// Getter et setter
public void setStartPt(Point startPt) {
this.startPt = startPt;
}
public void setEndPt(Point endPt) {
this.endPt = endPt;
}
public void setCurrentPt(Point currentPt) {
this.currentPt = currentPt;
}
public int getZoomCalculateX(int value){
return (int) (value / zoomFactor);
}
public int getZoomCalculateY(int value){
return (int) (value / zoomFactor);
}
public void setZoomer(boolean zoomer) {
this.zoomer = zoomer;
}
}
EDIT : Bellow is the class (simplified) that uses DrawingPanel so you can have a reproducible exemple.
package GUI;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.filechooser.FileNameExtensionFilter;
import org.apache.commons.io.FilenameUtils;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;
import fileHandler.*;
public class GUI {
private JFrame frame;
private MenuBar menubar;
private DrawingPanel panelImage;
private JScrollPane scroll;
private GroundTruth openFile;
private int[] panelImageDown = new int[2];
private int[] panelImageUp = new int[2];
private Menu CoordinateMenu1 = new Menu();
private Menu CoordinateMenu2 = new Menu();
private int actualPagePdf;
private PDFRenderer renderer;
public static void main(String[] args) throws IOException {
new GUI();
}
public GUI() throws IOException {
JFrame frame = CreateFrame();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private JFrame CreateFrame() throws IOException {
frame = new JFrame();
frame.setMenuBar(CreateMenuBar());
frame.setContentPane(SplitScreen());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setTitle("GTA - Ground Truth Annotator");
frame.setExtendedState(frame.getExtendedState() | JFrame.MAXIMIZED_BOTH);
return frame;
}
private MenuBar CreateMenuBar() {
menubar = new MenuBar();
menubar.add(CreateFileMenu());
menubar.add(new Menu("Selection coordinates:"));
menubar.add(CoordinateMenu1);
menubar.add(new Menu("Width/Height:"));
menubar.add(CoordinateMenu2);
return menubar;
}
private Menu CreateFileMenu() {
Menu mFile = new Menu("File");
MenuItem miOpenImage = new MenuItem("Open Image/PDF File");
mFile.add(miOpenImage);
miOpenImage.addActionListener(OpenFileActionListener);
mFile.addSeparator();
MenuItem miExit = new MenuItem("Exit Program");
mFile.add(miExit);
miExit.addActionListener(ExitActionListener);
return mFile;
}
private JPanel SplitScreen() throws IOException {
JPanel splittedScreen = new JPanel(new GridLayout(1, 2));
splittedScreen.add(CreateLeftPanel());
splittedScreen.add(CreateRightPanel());
return splittedScreen;
}
private JLayeredPane CreateLeftPanel() throws IOException {
JLayeredPane panel = new JLayeredPane();
panel.setLayout(new BorderLayout());
panel.setBorder(BorderFactory.createLineBorder(Color.gray));
panel.add(CreateImageScrollPane());
return panel;
}
private JScrollPane CreateImageScrollPane() throws IOException {
scroll = new JScrollPane(CreateImagePanel((String) null));
scroll.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
scroll.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
scroll.getViewport().setScrollMode(JViewport.BLIT_SCROLL_MODE);
return scroll;
}
private DrawingPanel CreateImagePanel(String path) throws IOException {
if (panelImage == null) {
panelImage = new DrawingPanel();
}
if (path != null) {
panelImage.loadImage(ImageIO.read(new File(path)));
}
panelImage.addMouseListener(PanelImageMouseListener);
panelImage.addMouseWheelListener(PanelImageMouseWheelListener);
panelImage.addMouseMotionListener(PanelImageMouseMotionAdapter);
panelImage.setOpaque(false);
panelImage.revalidate();
panelImage.repaint();
panelImage.requestFocus();
return panelImage;
}
private DrawingPanel CreateImagePanel(Image image) throws IOException {
if (panelImage == null) {
panelImage = new DrawingPanel();
}
panelImage.loadImage(image);
panelImage.addMouseListener(PanelImageMouseListener);
panelImage.addMouseWheelListener(PanelImageMouseWheelListener);
panelImage.addMouseMotionListener(PanelImageMouseMotionAdapter);
panelImage.setOpaque(false);
panelImage.revalidate();
panelImage.repaint();
return panelImage;
}
private JPanel CreateRightPanel() {
JPanel panel = new JPanel(new GridLayout(0, 1));
//...
return panel;
}
ActionListener OpenFileActionListener = new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
OpenFile();
}
};
ActionListener ExitActionListener = new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Object[] options = {"Yes, quit now", "No, go back"};
int n = JOptionPane.showOptionDialog(
frame, "ATTENTION: closing without saving will cause any unsaved files to be lost. Do you want to proceed?",
"Warning", JOptionPane.YES_NO_OPTION, JOptionPane.WARNING_MESSAGE, null, options, options[0]
);
switch (n) {
case JOptionPane.YES_OPTION:
System.exit(0);
case JOptionPane.NO_OPTION:
case JOptionPane.CANCEL_OPTION:
}
}
};
MouseListener PanelImageMouseListener = new MouseListener() {
public void mousePressed(MouseEvent me) {
panelImageDown = new int[]{
panelImage.getZoomCalculateX(me.getX()), panelImage.getZoomCalculateY(me.getY())
};
panelImageUp = null;
CoordinateMenu1.setLabel(String.format("%s:%s", panelImageDown[0], panelImageDown[1]));
CoordinateMenu2.setLabel("");
panelImage.setStartPt(me.getPoint());
panelImage.repaint();
}
public void mouseReleased(MouseEvent me) {
panelImageUp = new int[]{
Math.abs(panelImage.getZoomCalculateX(me.getX()) - panelImageDown[0]),
Math.abs(panelImageDown[1] - panelImage.getZoomCalculateY(me.getY()))
};
CoordinateMenu2.setLabel(String.format("%s:%s", panelImageUp[0], panelImageUp[1]));
panelImage.setEndPt(me.getPoint());
panelImage.setCurrentPt(null);
panelImage.repaint();
}
public void mouseClicked(MouseEvent arg0) {
}
public void mouseEntered(MouseEvent arg0) {
}
public void mouseExited(MouseEvent arg0) {
}
};
MouseMotionAdapter PanelImageMouseMotionAdapter = new MouseMotionAdapter() {
#Override
public void mouseDragged(MouseEvent me) {
panelImageUp = new int[]{
Math.abs(panelImage.getZoomCalculateX(me.getX()) - panelImageDown[0]),
Math.abs(panelImageDown[1] - panelImage.getZoomCalculateY(me.getY()))
};
CoordinateMenu2.setLabel(String.format("%s:%s", panelImageUp[0], panelImageUp[1]));
panelImage.setCurrentPt(me.getPoint());
panelImage.repaint();
}
};
MouseWheelListener PanelImageMouseWheelListener = new MouseWheelListener() {
public void mouseWheelMoved(MouseWheelEvent me) {
if (me.isAltDown()) {
if (me.getWheelRotation() < 0) {
panelImage.setZoomer(true);
panelImage.increaseZoom();
panelImage.repaint();
panelImage.requestFocus();
//scroll.repaint();
//Zoom out
} else if(me.getWheelRotation() > 0) {
panelImage.setZoomer(true);
panelImage.decreaseZoom();
panelImage.repaint();
panelImage.requestFocus();
//scroll.repaint();
}
}
}
};
private void OpenFile() {
openFile = new GroundTruth();
JFileChooser fileChooser = new JFileChooser();
fileChooser.setCurrentDirectory(new File(System.getProperty("user.home")));
fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
fileChooser.setAcceptAllFileFilterUsed(false);
fileChooser.addChoosableFileFilter(new FileNameExtensionFilter(
"Images / PDF Scan",
"bmp", "jpeg", "jpg", "png", "tif", "tiff", "pdf"
));
if (fileChooser.showOpenDialog(frame) != 0) {
return;
}
openFile.setFilename(fileChooser.getSelectedFile().getAbsolutePath());
if (getExtension(fileChooser.getSelectedFile().getName()).equals("pdf")) {
try {
PDDocument doc = PDDocument.load(fileChooser.getSelectedFile());
numberPagePdf = doc.getNumberOfPages();
actualPagePdf = 0;
renderer = new PDFRenderer(doc);
setPdfPage(actualPagePdf);
} catch (IOException e) {
e.printStackTrace();
}
} else {
try {
CreateImagePanel(fileChooser.getSelectedFile().getAbsolutePath());
} catch (IOException e) {
e.printStackTrace();
}
}
}
private void setPdfPage(int pageNumber){
try {
BufferedImage bim = renderer.renderImageWithDPI(pageNumber, 300);
refreshInfoPageSection();
CreateImagePanel(bim);
} catch (IOException e) {
e.printStackTrace();
}
}
// refresh the label who indicate the page display and set visible or inivisble the previous and next button
private void refreshInfoPageSection(){
panelImage.deleteRectangle();
}
public String getExtension(String filename) {
return FilenameUtils.getExtension(filename);
}
}

Here's a simplified example of a drawing JPanel that's larger than the scrolling JPanel.
You can see in the image that the drawing JPanel is larger both horizontally and vertically than the scrolling JPanel.
I don't call the paintComponent method at all in this code. Because I set up the GUI properly, Swing itself calls the repaint method when you move the scroll bars.
Here are the important things I did.
I started the Swing GUI with a call to the SwingUtilities invokeLater method. This method makes sure that the Swing components are created and executed on the Event Dispatch Thread.
I used a JFrame, two JPanels, and a JScrollPane. I extended JPanel to create the drawing panel. I used a JScrollPane, JPanel, and JFrame. The only time you extend a Swing component, or any Java class, is when you want to override one or more class methods.
I used Swing layout managers. I used a BorderLayout for the JFrame and scrolling JPanel.
Here's the complete runnable code. Why, you can even call it a minimal reproducible example!
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.SwingUtilities;
public class LargeDrawingPanel implements Runnable {
public static void main(String[] args) {
SwingUtilities.invokeLater(new LargeDrawingPanel());
}
#Override
public void run() {
JFrame frame = new JFrame("Large Drawing Panel");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(createMainPanel(), BorderLayout.CENTER);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
private JPanel createMainPanel() {
JPanel panel = new JPanel(new BorderLayout());
panel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
panel.setPreferredSize(new Dimension(400, 400));
JScrollPane scrollPane = new JScrollPane(new DrawingPanel());
panel.add(scrollPane, BorderLayout.CENTER);
return panel;
}
public class DrawingPanel extends JPanel {
private static final long serialVersionUID = 1L;
public DrawingPanel() {
this.setBackground(Color.WHITE);
this.setPreferredSize(new Dimension(2000, 2000));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.BLUE);
int x = 100;
int y = 100;
for (int i = 0; i < 10; i++) {
for (int j = 0; j < 10; j++) {
g.fillRect(x, y, 100, 100);
x += 200;
}
y += 200;
x = 100;
}
}
}
}
Edited to add: The OP posted additional questions in a comment.
Thanks for the example but it doesn't show me how to print an image in
a JPanel.
Pretty simple. Read an image using the ImageIO class, save the image in an application model consisting of one or more plain Java getter / setter classes and use the Graphics drawImage method to draw the image.
Your preview has only one scrollbar moved not both - which is my
problem.
Did you actually run the code I provided? I can only move one scrollbar at a time. The drawing JPanel extends both horizontally and vertically.
And it doesn't explain why my example doesn't work.
Your example is riddled with errors. Start over, building a Swing application one Swing component at a time using sound principles. The Oracle tutorial, Creating a GUI With JFC/Swing, will show you the correct way to create a Swing application. You can skip the Netbeans section.

Java JButton two or more icons

I would like to set two or more icons to one JButton (Java, Swing). Is it possible?
I add picture made in drawing. ;-)

The best way to achieve this is by creating a custom class that implements the Icon interface, which simply paints two given icons side by side.
public class TwoIcon implements Icon {
private final int iconGap = 2;
private final Icon icon1;
private final Icon icon2;
public TwoIcon(final Icon icon1, final Icon icon2) {
this.icon1 = icon1;
this.icon2 = icon2;
}
#Override
public void paintIcon(Component c, Graphics g, int x, int y) {
int mid = getIconHeight() / 2;
int y1 = y + mid - icon1.getIconHeight() / 2;
int y2 = y + mid - icon2.getIconHeight() / 2;
icon1.paintIcon(c, g, x, y1);
icon2.paintIcon(c, g, x + icon1.getIconWidth() + iconGap, y2);
}
#Override
public int getIconWidth() {
return icon1.getIconWidth() + icon2.getIconWidth() + iconGap;
}
#Override
public int getIconHeight() {
return Math.max(icon1.getIconHeight(), icon2.getIconHeight());
}
}
The icons will be painted side by side with a padding of 2 and centered vertically.
Play around with the spacing if you want them to be aligned differently.
Icon leftIcon = ...
Icon rightIcon = ...
button.setIcon(new TwoIcon(leftIcon, rightIcon));
Result:
I am simply using Icons that paint a solid colour here. One is 16x16 and the other 20x20 in size to demonstrate the vertical alignment.
In fact this is not restricted to JButton and will for any JComponent that can use an icon e.g. JLabel etc.

Are those two icons (happy / sad) literally the icons required? If so, I'd suggest instead using a JCheckBox and setting the icons as the default and selected icon (so the check box changes between them on selection).
Here's how (using a red icon for happy, and blue icon for sad).
import java.awt.*;
import java.io.IOException;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.net.*;
import javax.imageio.ImageIO;
public class CheckBoxWithIcons {
private JComponent ui = null;
Image happyImage;
Image sadImage;
CheckBoxWithIcons() {
try {
initUI();
} catch (Exception ex) {
ex.printStackTrace();
}
}
public final void initUI() throws MalformedURLException, IOException {
if (ui!=null) return;
happyImage = ImageIO.read(new URL("https://i.stack.imgur.com/wCF8S.png"));
sadImage = ImageIO.read(new URL("https://i.stack.imgur.com/gJmeJ.png"));
ui = new JPanel(new BorderLayout(4,4));
ui.setBorder(new EmptyBorder(4,100,4,100));
JCheckBox checkBox = new JCheckBox("Mood", true);
checkBox.setIcon(new ImageIcon(sadImage));
checkBox.setSelectedIcon(new ImageIcon(happyImage));
ui.add(checkBox);
}
public JComponent getUI() {
return ui;
}
public static void main(String[] args) {
Runnable r = () -> {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (Exception useDefault) {
}
CheckBoxWithIcons o = new CheckBoxWithIcons();
JFrame f = new JFrame(o.getClass().getSimpleName());
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setContentPane(o.getUI());
f.pack();
f.setMinimumSize(f.getSize());
f.setVisible(true);
};
SwingUtilities.invokeLater(r);
}
}

PipeGame -Why are the game objects not moving?

I'm wondering why my game objects are not showing. I am able to draw to the JPanel if I use g.drawRect outside of the for-each loop, but calling PipeObject inside of the loop doesn't seem to work for me. Am I doing something wrong here? Thanks for any help or solutions.
This is an updated version of my old question, which can be found here.
UPDATE - The pipes are drawing correctly, but not moving to the left by calling pipe.move().
Game
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
import javax.swing.JFrame;
import javax.swing.JPanel;
//import javax.swing.border.EmptyBorder;
import javax.swing.SwingUtilities;
public class Game {
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
// the GUI as seen by the user (without frame)
final CardLayout cl = new CardLayout();
final JPanel gui = new JPanel(cl);
// remove if no border is needed
//gui.setBorder(new EmptyBorder(10,10,10,10));
JPanel menu = new JPanel(new GridBagLayout());
JButton playGame = new JButton("Play!");
ActionListener playGameListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cl.show(gui, "game");
}
};
playGame.addActionListener(playGameListener);
Insets margin = new Insets(20, 50, 20, 50);
playGame.setMargin(margin);
menu.add(playGame);
gui.add(menu);
cl.addLayoutComponent(menu, "menu");
final JPanel pipes = new Pipes();
gui.add(pipes);
cl.addLayoutComponent(pipes, "game");
JFrame f = new JFrame("PipeGame");
f.add(gui);
// Ensures JVM closes after frame(s) closed and
// all non-daemon threads are finished
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
// See https://stackoverflow.com/a/7143398/418556 for demo.
f.setLocationByPlatform(true);
// ensures the frame is the minimum size it needs to be
// in order display the components within it
f.pack();
// should be done last, to avoid flickering, moving,
// resizing artifacts.
f.setVisible(true);
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency
SwingUtilities.invokeLater(r);
}
}
Pipes
import java.util.*;
import java.awt.Graphics;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Pipes extends JPanel {
boolean gameNotOver = true;
int x1 = 754;
int y1 = setHeightVal();
int y2 = setHeightVal();
int y3 = setHeightVal();
List<PipeObject> pipes = new ArrayList<PipeObject>();
public Pipes() {
pipes.add(new PipeObject(x1, y1));
pipes.add(new PipeObject(x1 + 300, y2));
pipes.add(new PipeObject(x1 + 600, y3));
}
public void drawEndlessPipes() {
if (gameNotOver) {
Timer pipeSpeed = new Timer(10, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
for (PipeObject pipe : pipes) {
pipe.move();
}
}
});
pipeSpeed.start();
}
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (PipeObject pipe : pipes) {
pipe.drawPipe(g);
}
}
public int setHeightVal() { //Get a random number and select a preset height
int num = (int)(9*Math.random() + 1);
int val = 0;
if (num == 9)
{
val = 295;
}
else if (num == 8)
{
val = 246;
}
else if (num == 7)
{
val = 216;
}
else if (num == 6)
{
val = 185;
}
else if (num == 5)
{
val = 156;
}
else if (num == 4)
{
val = 125;
}
else if (num == 3)
{
val = 96;
}
else if (num == 2)
{
val = 66;
}
else
{
val = 25;
}
return val;
}
public Dimension getPreferredSize() {
return new Dimension(751,501);
}
}
PipeObject
import java.awt.Graphics;
public class PipeObject {
//Declare and initialiaze variables
int x1;
int x2 = 75; //pipe width, total is 83
int y1 = -1; // Y should be -1
int y2;
int gap = 130; //gap height
public PipeObject(int x, int y) {
this.x1 = x;
this.y2 = y;
}
public void drawPipe(Graphics g/*, int x1, int y2*/) {
g.drawRect(x1,y1,x2,y2); //Draw part 1
g.drawRect(x1-3,y2-1,x2+6,25); //Draw part 2
g.drawRect(x1-3,y2+25+gap,x2+6,25); //Draw part 3
g.drawRect(x1,y2+25+gap+25,x2,500-y2-49-gap); //Draw part 4
}
public void move() {
x1--;
}
public int getMyX() { //To determine where the pipe is horizontally
return x1-3;
}
public int getMyY() { //To determine where the pipe is vertically
return y2+25;
}
}

You are painting the pipes beyond the visual bounds of the panel. The dimension of Pipes panel is 751x501, but the pipes begin at x1 = 754. Try changing x1 to 1 in Pipes and you should see the three pipes. Or, you can maximize the frame, and you should see the missing pipes far on the right side.

As CyberStorm said, you never called drawEndlessPipes() to start the swing timer at all.
Also I don't see a repaint() call to Pipes panel inside your timer, just changing the x value won't magically move anything, you need to call repaint() in Pipes.java to make it repaint the screen and show animation.
So here it goes:
Modified Runnable in Game.java
Runnable r = new Runnable() {
#Override
public void run() {
// the GUI as seen by the user (without frame)
final CardLayout cl = new CardLayout();
final JPanel gui = new JPanel(cl);
// remove if no border is needed
//gui.setBorder(new EmptyBorder(10,10,10,10));
JPanel menu = new JPanel(new GridBagLayout());
JButton playGame = new JButton("Play!");
ActionListener playGameListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cl.show(gui, "game");
}
};
playGame.addActionListener(playGameListener);
Insets margin = new Insets(20, 50, 20, 50);
playGame.setMargin(margin);
menu.add(playGame);
gui.add(menu);
cl.addLayoutComponent(menu, "menu");
final JPanel pipes = new Pipes();
gui.add(pipes);
cl.addLayoutComponent(pipes, "game");
JFrame f = new JFrame("PipeGame");
f.add(gui);
// Ensures JVM closes after frame(s) closed and
// all non-daemon threads are finished
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
// See http://stackoverflow.com/a/7143398/418556 for demo.
f.setLocationByPlatform(true);
// ensures the frame is the minimum size it needs to be
// in order display the components within it
f.pack();
// should be done last, to avoid flickering, moving,
// resizing artifacts.
f.setVisible(true);
((Pipes) pipes).drawEndlessPipes();
}
};
Modified drawEndlessPipes() in Pipes.java
public void drawEndlessPipes() {
if (gameNotOver) {
Timer pipeSpeed = new Timer(10, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
for (PipeObject pipe : pipes) {
pipe.move();
Pipes.this.repaint();
}
}
});
pipeSpeed.start();
}
}

Scrolling Hyperlinks in java

I'm about to embark on writing a (I think it will be) quick program involving a pulling headlines from a stock website and inserting them into an ArrayList of a class I'm going to create called Funds/Tickers/WhatHaveYou. That's not the huge problem. The main problem I have is this:
I want to have just one window, and that window will just continuously scroll the headlines. You can click on the headlines and that will bring up a browser to the article to read.
I initially thought you could do this with JLabels, but I did a few experiments and I could only get Strings to move accross the screen, not JLabels/JButtons/clickable things. Is there a way I can have JLabels or hyperlinks scroll accross the window in Java?
Cheers,
David

I want to have just one window, and that window will just continuously scroll the headlines.
You can use the Marquee Panel for this.
You can click on the headlines and that will bring up a browser to the article to read.
The above class doesn't support clicking on the components. However, I have been playing around a little with this concept. It seems to work OK when using a JLabel but I don't think it works for other components.
1) First you need to add a couple of methods to the MarqueePanel class that will translate the mouse point to map to the real component on the panel (in case you are using the wrapping option):
#Override
public Component getComponentAt(int x, int y)
{
Point translated = getTranslatedPoint(x, y);
for (Component c: getComponents())
{
if (c.getBounds().contains(translated))
return c;
}
return null;
}
public Point getTranslatedPoint(int x, int y)
{
int translatedX = x + scrollOffset;
if (isWrap())
{
int preferredWidth = super.getPreferredSize().width;
preferredWidth += getWrapAmount();
translatedX = translatedX % preferredWidth;
}
return new Point(translatedX, y);
}
2) Then you can add a MouseListener to the panel. With code like the following you can now access the label that was clicked:
marquee.addMouseListener( new MouseAdapter()
{
#Override
public void mousePressed(MouseEvent e)
{
Component c = marquee.getComponentAt(e.getPoint());
if (c == null) return;
if (c insstanceof JLabel)
{
JLabel label = (JLabel)c;
System.out.println(label.getText());
}
}
});

In this example, entries from an RSS feed are added to a JTextPane. A HyperlinkListener can be added to receive events representing clicks on hyerlinks.

Maybe what you need is a a EditorPane:
http://docs.oracle.com/javase/tutorial/uiswing/components/editorpane.html
Hope it helps.

I was working on this yesterday, when you first posted your question. I got tired and stopped messing with it. Basically what I did was use JPanel, and set their locations with each timer tick. I doubt it's the most optimal way, and I got really tired of trying to fix some of the problem, so I just stopped. You're free to play around with it, see if you can get any better results from it. The most frustrating part is when you click the panel, everything shifts for a quick second. Hopefully you can do something with it, or at least get some ideas. I just didn't want to scrap it, in case maybe you could make something of it.
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.LinkedList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class TestLabelMove {
List<MovingLabel> labels;
private int count = 1;
private JLabel statusLabel;
private final int SEPARATION = 100;
private final int SCREEN_W = 800;
int XLOC = SCREEN_W;
public TestLabelMove() {
statusLabel = new JLabel("Status");
statusLabel.setHorizontalAlignment(JLabel.CENTER);
JFrame frame = new JFrame("Test Labels");
frame.add(statusLabel, BorderLayout.CENTER);
frame.add(new LabelPanel(), BorderLayout.SOUTH);
frame.setSize(800, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private class LabelPanel extends JPanel {
private static final int INC = 5;
public LabelPanel() {
labels = new LinkedList<>();
for (int i = 0; i < 8; i++) {
MovingLabel label = new MovingLabel(XLOC);
labels.add(label);
XLOC -= SEPARATION;
add(label);
}
Timer timer = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
for (MovingLabel label : labels) {
if (isWrap(label.getXLoc())) {
label.setXLoc(SCREEN_W);
label.setLocation(label.getXLoc(), 0);
} else {
label.setLocation(label.getXLoc(), 0);
label.setXLoc(label.getXLoc() - INC);
}
}
}
});
timer.start();
}
}
public boolean isWrap(int x) {
return x <= -40;
}
private class MovingLabel extends JPanel {
int xLoc;
String phrase;
public MovingLabel(int xLoc) {
this.xLoc = xLoc;
phrase = "Panel " + count;
count++;
this.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
statusLabel.setText(phrase);
repaint();
}
});
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Font font = new Font("Helvetica", Font.BOLD, 14);
FontMetrics fm = g.getFontMetrics(font);
int w = fm.stringWidth(phrase);
int h = fm.getAscent();
g.setFont(font);
g.drawString(phrase, getWidth()/2 - w/2, getHeight()/2 + h/2);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(100, 20);
}
public void setXLoc(int xLoc) {
this.xLoc = xLoc;
}
public int getXLoc() {
return xLoc;
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new TestLabelMove();
}
});
}
}

Optimal location for a modal JDialog to avoid stuck

My Swing application has to show a modal dialog to the user. Sorry for not posting SSCCE.
topContainer might be JFrame or JApplet.
private class NewGameDialog extends JDialog {
public NewGameDialog () {
super(SwingUtilities.windowForComponent(topContainer), "NEW GAME", ModalityType.APPLICATION_MODAL);
//add components here
getContentPane().setLayout(new BoxLayout(getContentPane(), BoxLayout.Y_AXIS));
//TODO:
setSize(new Dimension(250, 200));
setLocation(650, 300);
}
}
I start the dialog like this on network event
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
NewGameDialog dialog = new NewGameDialog();
dialog.setVisible(true);
}
});
The problem is to set optimal location for my dialog.
1) If it is set as absolute value, and I move the app frame to the second screen, then dialog is shown on the first screen which is weird.
2) If it is set a relative value to JFrame, it might appear that user moved the app frame outside of the screen and the dialog being relatively located would not be visible to the user. And because it is modal, the game would be stuck.
What is the best solution considering two above mentioned issues?

This reminded me of a very favourite post of mine, using Window.setLocationByPlatform(true), on StackOverflow.
How to best position Swing GUIs
EDIT 1 :
You can add a FocusListener to your JDialog and on focusGained(...) method, you can use setLocationRelativeTo(null) for both the JFrame and the JDialog, so that they both come to the center of the screen no matter where they are before.
import java.awt.*;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
/**
* Created with IntelliJ IDEA.
* User: Gagandeep Bali
* Date: 1/14/13
* Time: 7:34 PM
* To change this template use File | Settings | File Templates.
*/
public class FrameFocus
{
private JFrame mainwindow;
private CustomDialog customDialog;
private void displayGUI()
{
mainwindow = new JFrame("Frame Focus Window Example");
customDialog = new CustomDialog(mainwindow, "Modal Dialog", true);
mainwindow.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
JPanel contentPane = new JPanel();
JButton mainButton = new JButton(
"Click me to open a MODAL Dialog");
mainButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (!customDialog.isShowing())
customDialog.setVisible(true);
}
});
contentPane.add(mainButton);
mainwindow.setContentPane(contentPane);
mainwindow.pack();
mainwindow.setLocationByPlatform(true);
mainwindow.setVisible(true);
}
public static void main(String... args)
{
EventQueue.invokeLater(new Runnable()
{
#Override
public void run()
{
new FrameFocus().displayGUI();
}
});
}
}
class CustomDialog extends JDialog
{
private JFrame mainWindow;
public CustomDialog(JFrame owner, String title, boolean modal)
{
super(owner, title, modal);
mainWindow = owner;
JPanel contentPane = new JPanel();
JLabel dialogLabel = new JLabel(
"I am a Label on JDialog.", JLabel.CENTER);
contentPane.add(dialogLabel);
setContentPane(contentPane);
pack();
addFocusListener(new FocusListener() {
#Override
public void focusGained(FocusEvent e) {
mainWindow.setLocationRelativeTo(null);
setLocationRelativeTo(null);
}
#Override
public void focusLost(FocusEvent e) {
/*
* Nothing written for this part yet
*/
}
});
}
}
EDIT 2 :
I searched a bit here and there, and it turns out, in my opinion, that actually on which Monitor Screen your application comes at the first instance, will determine it's GraphicsConfiguration. Though as I roamed through the API, there is only a getter method for the said GraphicsConfiguration thingy and no setter methods for the same (Still You can specify one through the constructor of any top level Window i.e. JFrame(...)/JDialog(...)).
Now you can occupy your head with this code, which can be used to determine the appropriate location, that you want to set, again, you might have to use focusGain() method in my opinion, to satisfy condition 2 of your question. Have a look at the code attached, though no need to create a new JFrame/JDialog, just watch how to get coordinates for the screen (that you can add in the focusGain() method to determine the location of the whole Application.)
GraphicsEnvironment ge = GraphicsEnvironment.
getLocalGraphicsEnvironment();
GraphicsDevice[] gs = ge.getScreenDevices();
for (int j = 0; j < gs.length; j++) {
GraphicsDevice gd = gs[j];
GraphicsConfiguration[] gc =
gd.getConfigurations();
for (int i=0; i < gc.length; i++) {
JFrame f = new
JFrame(gs[j].getDefaultConfiguration());
Canvas c = new Canvas(gc[i]);
Rectangle gcBounds = gc[i].getBounds();
int xoffs = gcBounds.x;
int yoffs = gcBounds.y;
f.getContentPane().add(c);
f.setLocation((i*50)+xoffs, (i*60)+yoffs);
f.show();
}
}
EDIT 3 :
Try to change this :
int x = loc.getX() + (mainWindow.getWidth() - getWidth()) / 2;
int y = loc.getY() + (mainWindow.getHeight() - getHeight()) / 2;
setLocation(x, y);
to just :
setLocationRelativeTo(mainWindow);
To test the above thingy, I used my FrameFocus Class as is, though I had added your changes to my CustomDialog method, as shown in this modified CustomDialog Class.
class CustomDialog extends JDialog
{
private JFrame mainWindow;
public CustomDialog(JFrame owner, String title, boolean modal)
{
super(owner, title, modal);
mainWindow = owner;
JPanel contentPane = new JPanel();
JLabel dialogLabel = new JLabel(
"I am a Label on JDialog.", JLabel.CENTER);
contentPane.add(dialogLabel);
setContentPane(contentPane);
pack();
addFocusListener(new FocusListener() {
#Override
public void focusGained(FocusEvent e) {
//mainWindow.setLocationRelativeTo(null);
//setLocationRelativeTo(null);
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice[] gs = ge.getScreenDevices();
for (int j = 0; j < gs.length; j++) {
GraphicsDevice gd = gs[j];
GraphicsConfiguration[] gc = gd.getConfigurations();
for (int i=0; i < gc.length; i++) {
Rectangle gcBounds = gc[i].getBounds();
Point loc = mainWindow.getLocationOnScreen();
if (gcBounds.contains(loc)) {
System.out.println("at " + j + " screen");
int x = gcBounds.x + (gcBounds.width - mainWindow.getWidth()) / 2;
int y = gcBounds.y + (gcBounds.height - mainWindow.getHeight()) / 2;
mainWindow.setLocation(x, y);
//x = (int) (loc.getX() + (mainWindow.getWidth() - CustomDialog.this.getWidth()) / 2);
//y = (int) (loc.getY() + (mainWindow.getHeight() - CustomDialog.this.getHeight()) / 2);
//CustomDialog.this.setLocation(x, y);
CustomDialog.this.setLocationRelativeTo(mainWindow);
break;
}
}
}
}
#Override
public void focusLost(FocusEvent e) {
/*
* Nothing written for this part yet
*/
}
});
}
}

I think, best would be to center the dialog in the middle of the current screen as described here.
Toolkit toolkit = Toolkit.getDefaultToolkit();
Dimension screenSize = toolkit.getScreenSize();
int x = (screenSize.width - d.getWidth()) / 2;
int y = (screenSize.height - d.getHeight()) / 2;
d.setLocation(x, y);
This always works and how it can be invisible to the user if it is right in the center of the screen? And setLocationRelativeTo can also be used but you need to invoke it at the right time.

use JDialog.setLocation() for moving JDialog on desired Point on the screen
import java.awt.GridLayout;
import java.awt.Point;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.EmptyBorder;
public class JDialogAtPoint {
private JFrame frame = new JFrame();
private JPanel panel = new JPanel();
private JDialog dialog;
private Point location;
public JDialogAtPoint() {
createGrid();
createDialog();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(panel);
frame.setLocation(100, 100);
frame.pack();
frame.setVisible(true);
}
private void createGrid() {
panel.setLayout(new GridLayout(3, 3, 4, 4));
int l = 0;
int row = 3;
int col = 3;
JButton buttons[][] = new JButton[row][col];
for (int i = 0; i < row; i++) {
for (int j = 0; j < col; j++) {
buttons[i][j] = new JButton("");
buttons[i][j].putClientProperty("column", i + 1);
buttons[i][j].putClientProperty("row", j + 1);
buttons[i][j].setAction(updateCol());
panel.add(buttons[i][j]);
l++;
}
}
}
private void createDialog() {
dialog = new JDialog();
dialog.setAlwaysOnTop(true);
dialog.setModal(true);
dialog.setDefaultCloseOperation(JDialog.HIDE_ON_CLOSE);
JPanel pane = (JPanel) dialog.getContentPane();
pane.setBorder(new EmptyBorder(20, 20, 20, 20));
dialog.pack();
}
public Action updateCol() {
return new AbstractAction("Display JDialog at Point") {
private static final long serialVersionUID = 1L;
#Override
public void actionPerformed(ActionEvent e) {
JButton btn = (JButton) e.getSource();
System.out.println("Locations coordinates" + btn.getLocation());
System.out.println("clicked column "
+ btn.getClientProperty("column")
+ ", row " + btn.getClientProperty("row"));
if (!dialog.isVisible()) {
showingDialog(btn.getLocationOnScreen());
}
}
};
}
private void showingDialog(final Point loc) {
dialog.setVisible(false);
location = loc;
int x = location.x;
int y = location.y;
dialog.setLocation(x, y);
Runnable doRun = new Runnable() {
#Override
public void run() {//dialog.setLocationRelativeTo(frame);
dialog.setVisible(true);
}
};
SwingUtilities.invokeLater(doRun);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JDialogAtPoint cf = new JDialogAtPoint();
}
});
}
}

With the help of all 3 answerers I have come up with code which seems exactly what I need. First, JFrame got placed in the middle of current screen and then JDialog accordingly.
GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice[] gs = ge.getScreenDevices();
for (int j = 0; j < gs.length; j++) {
GraphicsDevice gd = gs[j];
GraphicsConfiguration[] gc = gd.getConfigurations();
for (int i=0; i < gc.length; i++) {
Rectangle gcBounds = gc[i].getBounds();
Point loc = mainWindow.getLocationOnScreen();
if (gcBounds.contains(loc)) {
System.out.println("at " + j + " screen");
int x = gcBounds.x + (gcBounds.width - mainWindow.getWidth()) / 2;
int y = gcBounds.y + (gcBounds.height - mainWindow.getHeight()) / 2;
mainWindow.setLocation(x, y);
int x = loc.getX() + (mainWindow.getWidth() - getWidth()) / 2;
int y = loc.getY() + (mainWindow.getHeight() - getHeight()) / 2;
setLocation(x, y);
break;
}
}
}