Develop Reference

cannot always load the picture on click and hover

I am making a launcher application, i wish to change the button depending on the action taken, right now i want to change the button when the following actions happen, either the player hovers over the image, clicks on the image, releases the image click or exits the hover. The issue i have is that it doesn't always load correctly, which is odd.
package LostStory;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.SystemTray;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.io.IOException;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JComponent;
#SuppressWarnings("serial")
public class LaunchPanel extends JComponent {
Image image;
JButton play;
SystemTray tray;
ImageIcon icon = new ImageIcon("res/images/buttons/playNonHover.png");
ImageIcon iconHover = new ImageIcon("res/images/buttons/playHover.png");
ImageIcon iconClick = new ImageIcon("res/images/buttons/playClick.png");
public LaunchPanel(Image img) {
this.image = img;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(image, 0, 0, this);
init();
}
public void init() {
play = new JButton("Play Lost Story", icon);
play.setBounds(85, 210 - 75, getWidth() - 165, 50);
play.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
Runtime run = Runtime.getRuntime();
try {
run.exec("notepad");
if (SystemTray.isSupported()) {
tray = SystemTray.getSystemTray();
play.setIcon(play.getIcon());
// Main.getClient().getJFrame().setVisible(false);
// tray.add(img);
}
} catch (IOException e) {
e.printStackTrace();
}
}
});
play.addMouseListener(new MouseListener() {
#Override
public void mouseClicked(MouseEvent arg0) {
} // no use
#Override
public void mouseEntered(MouseEvent e) {
if (iconHover.getImageLoadStatus() == 8) {
play.setIcon(iconHover);
play.setIcon(play.getIcon());
System.out.println("Entered");
}
System.out.println(iconHover.getImageLoadStatus());
} // use
#Override
public void mouseExited(MouseEvent arg0) {
if (icon.getImageLoadStatus() == 8) {
play.setIcon(icon);
play.setIcon(play.getIcon());
System.out.println("Exited");
}
System.out.println(icon.getImageLoadStatus());
} // use
#Override
public void mousePressed(MouseEvent arg0) {
if (iconClick.getImageLoadStatus() == 8) {
play.setIcon(iconClick);
play.setIcon(play.getIcon());
System.out.println("Pressed");
}
System.out.println(iconClick.getImageLoadStatus());
} // use
#Override
public void mouseReleased(MouseEvent arg0) {
if (icon.getImageLoadStatus() == 8) {
play.setIcon(icon);
play.setIcon(play.getIcon());
System.out.println("Released");
}
System.out.println(icon.getImageLoadStatus());
} // use
});
add(play);
}
}
The first button always loads (because it is the default one) it returned an '8' when i tried using the IconImage.getImageLoadStatus() so i expected that to be '8' if it was succesfully loaded. (This is not the case though, it will always return 8 as far as i know).
So TL;DR: How do i make sure the ImageIcons are always loaded and will apply correctly?

Don't try to manipulate the icon using the setIcon() method.
A JButton has methods to set the icon for various states setRolloverIcon, setPressedIcon, etc.
Read the API for other properties.
Also, a painting method is for painting only. Never create components from a painting method. Get rid of the init() method from your paintComponent() method.
Components should be created and added to the panel in the constructor of the panel.

Why does my AWT/swing GUI JAR capture stylus event data only in a specific region of the screen on a Windows 8.1 tablet?

QUESTION SUMMARY: I generated a .JAR file using Netbeans 7.2.1 for a Java Swing/AWT program developed on Windows 7 (Java version 1.8.0_40), that helps collect user handwriting from the screen. It runs fine on a Windows 7 notebook PC but due to some reason captures handwriting data only on a specific region of the screen on a Windows 8.1 tablet (Java version 1.8.0_45). Could someone kindly tell me why this is happening?
DETAILS: I have a requirement of collecting online handwriting samples (i.e. those acquired from electronic devices like a tablet PC using a pen/stylus and writing surface) for some analysis
Being new to developing programs of this nature, I read up about it on the web and decided to use the Java Swing/AWT toolkits
A person's handwriting is composed of strokes which are in turn composed of points. My objective was to capture:
- the X- and Y-coordinates of a point on the screen
- the timestamp of creation of this point
- the stroke's start-time, end-time and color (color not too important)
To this end I wrote the following program using Netbeans 7.2.1 IDE with Java 1.8.0_40 on a Windows 7 Home Basic OS
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package handwritingsamplerawt;
import java.awt.AWTException;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.*;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class HandwritingSamplerAWT {
static JFrame frame;
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
CreateAndShowGUI();
}
});
}
private static void CreateAndShowGUI() {
frame = new JFrame("Writing Surface v0.1");
frame.getContentPane().setLayout(new FlowLayout(FlowLayout.RIGHT));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBackground(Color.LIGHT_GRAY);
frame.pack();
frame.add(new MyPanel());
frame.setVisible(true);
}
}
class MyPanel extends JPanel{
private int x,y;
static int strokeIndex;
private long reducedMillis;
private ArrayList<StrokeInfo> strokes;
private JButton btnSave;
public MyPanel() {
MyPanel.strokeIndex=0;
this.reducedMillis = 1435800000000L;
this.strokes = new ArrayList<>();
this.btnSave = new JButton("SAVE SAMPLE");
this.btnSave.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
WriteCoordinates();
}
});
this.add(this.btnSave);
addMouseListener(new MouseAdapter() {
public void mousePressed(MouseEvent e) {
x=e.getX();
y=e.getY();
SaveCoordinates(x,y,"PRESSED");
repaint();
}
});
addMouseMotionListener(new MouseAdapter() {
public void mouseDragged(MouseEvent e) {
x=e.getX();
y=e.getY();
SaveCoordinates(x,y,"DRAGGED");
repaint();
}
});
addMouseListener(new MouseAdapter() {
public void mouseReleased(MouseEvent e) {
x=e.getX();
y=e.getY();
SaveCoordinates(x,y,"RELEASED");
repaint();
}
});
}
void SaveCoordinates(int xCoordinate, int yCoordinate, String actionIndicator){
try {
Calendar cal = Calendar.getInstance();
Date currDate = cal.getTime();
double timeStamp=(double)(currDate.getTime()-reducedMillis);
PointInfo pointObj = new PointInfo(xCoordinate, yCoordinate, timeStamp);
switch (actionIndicator) {
case "PRESSED":
StrokeInfo newStroke = new StrokeInfo();
newStroke.points.add(pointObj);
strokes.add(newStroke);
break;
case "DRAGGED":
strokes.get(strokeIndex).points.add(pointObj);
break;
case "RELEASED":
strokeIndex+=1;
break;
}
} catch (Exception ex){
String errMsg = ex.getMessage();
System.out.println(errMsg);
}
}
void WriteCoordinates() {
try {
Calendar cal = Calendar.getInstance();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");
String currTimeString = dateFormat.format(cal.getTime());
DecimalFormat decFormat = new DecimalFormat("#");
decFormat.setMaximumFractionDigits(2);
FileWriter writer = new FileWriter("D:\\HandwritingCaptures\\HandwritingText\\"+currTimeString+".txt");
SetStrokeAttributes(strokes);
ListIterator<PointInfo> pointItr;
if (strokes.isEmpty()==false) {
for (int index = 0; index < strokeIndex; index++) {
writer.write(strokes.get(index).colour);
writer.append('\t');
writer.write(decFormat.format( strokes.get(index).startTime));
writer.append('\t');
writer.write(decFormat.format( strokes.get(index).endTime));
writer.append('\n');
pointItr = strokes.get(index).points.listIterator();
while (pointItr.hasNext()) {
PointInfo currPoint = pointItr.next();
writer.write(String.valueOf(currPoint.x));
writer.append('\t');
writer.write(String.valueOf(currPoint.y));
writer.append('\t');
writer.write(decFormat.format(currPoint.timestamp));
writer.append('\n');
}
writer.append('#');
writer.append('\n');
}
}
writer.close();
SaveScreenshot("D:\\HandwritingCaptures\\Screenshots\\"+currTimeString+".png");
} catch (IOException ex) {
System.out.println(ex.getMessage());
}
}
void SetStrokeAttributes(ArrayList<StrokeInfo> strokeList) {
double startTime, endTime;
String colour;
StrokeInfo tmpStroke;
ArrayList<PointInfo> points;
if (strokeList.isEmpty() == false) {
for (int index = 0; index < strokeList.size(); index++) {
tmpStroke = strokeList.get(index);
points = tmpStroke.points;
tmpStroke.colour = "black";
tmpStroke.startTime=points.get(0).timestamp;
tmpStroke.endTime=points.get(points.size()-1).timestamp;
strokeList.set(index, tmpStroke);
}
}
}
void SaveScreenshot(String imgFilePath){
try {
Rectangle screenRect = new Rectangle(Toolkit.getDefaultToolkit().getScreenSize());
BufferedImage capture = new Robot().createScreenCapture(screenRect);
ImageIO.write(capture, "png", new File(imgFilePath));
} catch (IOException | AWTException ex) {
System.out.println(ex.getMessage());
}
}
public Dimension getPreferredSize() {
return new Dimension(1366,768);
}
protected void paintComponent(Graphics g) {
super.paintComponents(g);
g.setColor(Color.BLACK);
g.drawLine(x, y, x, y);
}
}
class PointInfo {
int x,y;
double timestamp;
public PointInfo(int px, int py, double ts) {
this.x=px;
this.y=py;
this.timestamp=ts;
}
}
class StrokeInfo {
ArrayList<PointInfo> points;
double startTime, endTime;
String colour;
public StrokeInfo() {
points= new ArrayList<>();
}
}
I generated the .jar file using the IDE itself (Project Properties-> Build-> Packaging-> Compress JAR file)
Then copied the .jar file to a HP EliteBook 2730P Notebook PC with JRE 1.7.0.800 and Windows 7 Pro OS (32-bit) where it ran fine collecting handwriting strokes from all areas of the screen
But when I copied the same .jar to a HP Elite x2 1011 G1 tablet with JRE 1.8.0_45 and Windows 8.1 (64-bit) and ran it, I found that strangely it captures stylus inputs ONLY from a specific region of the screen - more specifically towards the upper right. It is completely non-responsive on the other areas
Could someone please help me understand why this is happening? Would have posted couple screenshots here but my low reputation prevents me from doing so.
ADDITIONAL THOUGHTS: Would it be better to use .NET or Java FX for developing such a tool for using in a Windows 8.1 environment?

Your panel seems to have a fixed size:
return new Dimension(1366,768);
Is the resolution of your tablet bigger than that?
Edit:
This should help:
private static void CreateAndShowGUI() {
frame = new JFrame("Writing Surface v0.1");
// Using the default BorderLayout here.
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBackground(Color.LIGHT_GRAY);
frame.getContentPane().add(new MyPanel(), BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
However there are still problems with your layout, like the "Save" button jumping around. You should take a look at this tutorial:
https://docs.oracle.com/javase/tutorial/uiswing/layout/index.html

The fact that the problem could be related to the hardcoded dimensions became clear on seeing the behavior of the .jar file upon running
The tablet had a higher resolution (1920 x 1080 pixels - found by checking the screen resolution through a right click on the desktop) than the machine I had initially run the program on (1366 x 768 pixels). The dimensions of the writable area towards the upper right corner were infact true to the hardcoded dimensions
Ergo, I modified the overridden method getPreferredSize() in the following manner:
public Dimension getPreferredSize() {
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
return new Dimension((int)screenSize.getWidth(),(int)screenSize.getHeight());
}
This causes the preferred size components to take on the effective height and width of the screen of the device the .jar is executed on. This is important because depending on the layout manager used the treatment of the above method by it does differ
The "SAVE SAMPLE" button intermittently still seems to cast its images (non-clickable) on other areas of the screen - this probably might have something to do with the layout manager handling of the UI components. Shall add an edit for that issue too once I find a solution

Multiple instances of the same animated GIF in a Canvas (Java)

So I'm making a game where you can put bombs on the location of your character. Each bomb is associated with a GIF image when the bomb is displayed and eventually go BOOM (think about Bomberman).
The problem was, when i tried to paint more than one bomb on the screen, it was painted from the last frame of the GIF. Investigating, I found the method image.flush() to reset the GIF cicle but now the problem is that every time I paint a second bomb on the screen, the GIF cycle is reset for all previously bombs on screen.
Here is my constructor for each bomb:
public Tnt(int x, int y){
this.x = x;
this.y = y;
ImageIcon ii = new ImageIcon("src/main/resources/modelObjects/tnt.gif");
image = ii.getImage();
image.flush();
}
Every bomb i create enters an ArrayList (listTnt) and is removed after 6 secs, so i only paint the bombs already active.
Here is my method for drawing:
public void draw(Graphics2D g2d, JPanel board){
for(Tnt tnt: listTnt){
g2d.drawImage(tnt.getImage(), tnt.getX(), tnt.getY(), board);
}
}
EDIT: Seems that the problem was ImageIcon, since it reuses the image using Toolkit.getImage. Instead, Toolkit.createImage create a not reusable image.
Here is my new constructor for Tnt that worked perfectly:
public Tnt(int x, int y){
this.x = x;
this.y = y;
Toolkit t = Toolkit.getDefaultToolkit ();
image = t.createImage("src/main/resources/modelObjects/tnt.gif");
}
I dont even need image.flush() now. Thank you all.

The underlying Image is being reused amongst each ImageIcon.
Judging by the OpenJDK source code, it appears to be due to the fact that each simply requests the Image via Toolkit.getImage.
This method has a nifty caveat, however, which explains the issue at hand:
The underlying toolkit attempts to resolve multiple requests with the same filename to the same returned Image.
Instead, you should skip the ImageIcon step completely (since it's inappropriate to be using a Swing class unnecessarily in the first place), and instead call Toolkit.createImage, which states in the documentation:
The returned Image is a new object which will not be shared with any other caller of this method or its getImage variant.
Good luck.

As I did not know how to solve this, I tried #super_ solution and it works quite nicely. I share the code for anyone who wants an example. +1 to him
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.MalformedURLException;
import java.net.URL;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class TestAnimatedGif {
private static final int IMAGE_COUNT = 9;
protected void initUI() {
JFrame frame = new JFrame(TestAnimatedGif.class.getSimpleName());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final JPanel panel = new JPanel();
frame.add(panel);
frame.setSize(600, 400);
frame.setVisible(true);
final Timer t = new Timer(1000, null);
t.addActionListener(new ActionListener() {
int count = 0;
#Override
public void actionPerformed(ActionEvent e) {
if (count < IMAGE_COUNT) {
try {
JLabel image = new JLabel(new ImageIcon(Toolkit.getDefaultToolkit().createImage(
new URL("http://www.sitevip.net/gifs/bomba/BOMB-B_animado.gif"))));
panel.add(image);
count++;
panel.revalidate();
panel.repaint();
System.err.println("image added");
} catch (MalformedURLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
} else {
t.stop();
}
}
});
t.start();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new TestAnimatedGif().initUI();
}
});
}
}

How to change the mouse pointer to finger pointer in swing?

In html when we create a hyperlink and point over it ,then it automatically changes to a finger pointer.
So I was wondering can we achieve the same in java swings.
Suppose I have a label on clicking which a new form pops-up.But I want that when the user points over the label it should change to finger pointer,showing that something will pop-up if its clicked.In this way we can differentiate that label with normal labels on the form i guess :).
But how to do something like this?

You can set cursor of JLabel to Cursor.HAND_CURSOR using below code :
JLabel label = new JLabel("https://stackoverflow.com");
label.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));

go to the properties of the button or the label and scroll down you will find a column of cursor you can change to hand or whatever you want

As said you'd want to call the setCursor() method on the JLabel and set it to Cursor.Hand_CURSOR to further this you can also underline the text to make it an HTML look alike link if you want :):
import java.awt.Color;
import java.awt.Cursor;
import java.awt.Desktop;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.net.URI;
import javax.swing.JLabel;
/**
*
* #author ludovicianul
*/
public class URLLabel extends JLabel {
private String url;
public URLLabel() {
this("","");
}
public URLLabel(String label, String url) {
super(label);
this.url = url;
setForeground(Color.BLUE.darker());
setCursor(
new Cursor(Cursor.HAND_CURSOR));
addMouseListener(
new URLOpenAdapter());
}
public void setURL(String url) {
this.url = url;
}
//this is used to underline the text
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.blue);
Insets insets = getInsets();
int left = insets.left;
if (getIcon() != null) {
left += getIcon().getIconWidth() + getIconTextGap();
}
g.drawLine(left, getHeight() - 1 - insets.bottom, (int) getPreferredSize().getWidth()
- insets.right, getHeight() - 1 - insets.bottom);
}
private class URLOpenAdapter extends MouseAdapter {
#Override
public void mouseClicked(MouseEvent e) {
if (Desktop.isDesktopSupported()) {
try {
Desktop.getDesktop().browse(new URI(url));
} catch (Throwable t) {
//
}
}
}
}
}
Reference:
CREATING A URL JLABEL IN SWING

Hossein Mobasher
answer is good and mine answer is very late but i just want to add up you can also use it like this below.
JLabel label = new JLabel("http://stackoverflow.com");
label.setCursor(Cursor.HAND);
It will also work i have tried it in Java 1.8

ButtonName.SetCursor(new Cursor(12));
This one works definitely!

Java: Strange behavior of JEditorPane wrapped inside JScrollPane

I'm trying to build a simple help system to my software.
The help system built from JEditorPane(Loaded with HTML file) wrapped inside of JScrollPane, inside of the same window there is a JLabel.
When the user move the mouse over the JEditorPane on a specific word - more explanations appear in the JLabel.
I succeed doing it, but the problem is, that for some reason it work just on the beginning of the text.(the HTML file is long and must be scrolled...)
After i scroll down the page and hover over a word, it throw me BadLocationException.
On the code below there is a JEditorPane wrapped inside JScrollPane.
When the user move the mouse it print the current letter which the mouse point on.(on the help system i find the value of the word by this position and print explanations to the JLabel according to it)
But, as i said it work just on the beginning of the text.
Why ?
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.LayoutManager;
import java.awt.Point;
import java.io.IOException;
import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.text.BadLocationException;
public class JEditorPaneTestApp extends JFrame {
private JEditorPane editorPan;
private JScrollPane scrollPan;
public JEditorPaneTestApp() {
super();
try {
editorPan = new javax.swing.JEditorPane("file:///path/toHTML/file/helpFile.html");
}
catch (IOException e) {e.printStackTrace();}
scrollPan = new JScrollPane(editorPan);
this.add(scrollPan);
editorPan.addMouseMotionListener(new java.awt.event.MouseMotionAdapter() {
public void mouseMoved(java.awt.event.MouseEvent evt) {
Point p = new Point(evt.getX(), evt.getY());
int pos = editorPan.viewToModel(p);
try {
System.out.println(editorPan.getText(pos--, pos).charAt(0));
}
catch (BadLocationException e1) {
System.out.println("Invalid location");/* e1.printStackTrace();*/
}
}
});
scrollPan.setViewportView(editorPan);
this.add(scrollPan);
//
this.getContentPane().setLayout(new LayoutManager() {
#Override public Dimension preferredLayoutSize(Container arg0) {return null;}
#Override public Dimension minimumLayoutSize(Container arg0) {return null;}
#Override public void removeLayoutComponent(Component arg0) {}
#Override public void addLayoutComponent(String arg0, Component arg1) {}
#Override public void layoutContainer(Container conter) {
scrollPan.setBounds(0, 0, conter.getWidth(), conter.getHeight());
}
});
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
}
public static void main(String[] args) {
JEditorPaneTestApp test = new JEditorPaneTestApp();
}
}
Thanks

System.out.println(editorPan.getText(pos--, pos).charAt(0));
should be:
System.out.println(editorPan.getText(pos--, 1).charAt(0));