No refreshing, every time the same Image - java

Basically, I am trying to create an app, that displays images.
filename variable is a path to an image that I want to display. After I start an app, an Image is displayed, but then, when I remove the image from a hard drive (or change other image to the filename name) I don't get any other Image, just the same as before.
public static void main(final String[] args) {
String filename = "C:\\temp\\1.jpeg";
JFrame frame = new JFrame();
frame.getContentPane().add(new JLabel(new ImageIcon(filename)));
frame.pack();
frame.setVisible(true);
// Mouse Listener is only to display another JFrame after mouseClicked event
frame.addMouseListener(new MouseListener() {
public void mouseClicked(MouseEvent e) {
main(args);
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
});
}

The image is cached. You need to force it to reload by doing either:
// This works using ImageIO
imageLabel.setIcon( new ImageIcon(ImageIO.read( new File(imageName) ) ) );
// Or you can flush the image
ImageIcon icon = new ImageIcon(imageName);
icon.getImage().flush();
imageLabel.setIcon( icon );

If this is all the code there is, and you are moving files around on the OS, your application will not pick up the changes.
The image has been loaded and will always be told to draw the same way.
You could use a WatchService to watch for changes on the file (I think) or just periodically check to see if the file has changed.

That behaviour you are trying to achieve seems a bit unusual. If that is what you want to do you could set a timer that triggers an event periodically (every "n" seconds or whatever is appropriate), deletes the image icon object and adds a new one. Don't forget to call "pack()" at the end.

Related

Jslider can not tick when its value changed from JButton periodically

I am working on a swing project. There is a map, I have raster images of a given data for different times. Normally I change the time via a JSlider and it requests server for raster image. Then I add response image to map. There is a Play JButton, when pressed it will add those images one by one to raster layer of the map. It will be seen as an animation. In that JButton's actionPerfomed method I change the JSlider's value in a for loop.
My problem is when I press Play JButton, I can't see the data is played but I know code block works because I record each image(from server). I found out that it is becuse of JButton does not release Focus until its actionPerformed method ends. Because JButton looked like it was pressed until the end. So I only see the last image in the map.
First, I tried JButton.setFocusable(false) etc. but to no good.
Second, I tried using SwingWorker. I added it like this:
class PlayMvgmLayerWorker extends SwingWorker<Void, Void> {
public PlayMvgmLayerWorker(String title) {
super(title);
}
#Override
protected void done(Void aVoid) {
}
#Override
protected Void doInBackground() {
try{
BufferedImage[] image = new BufferedImage[24];
for(int i=0; i<24; i++) {
final int value = i - 48 + 24;
timeSlider.setValue( value );
Thread.sleep(10000l);
}
} catch(Exception ex) {
ex.printStackTrace();
}
return null;
}
}
private JButton animation = new JButton("");
animation.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
new PlayMvgmLayerWorker("title").execute();
}
});
private JSlider timeSlider = new JSlider();
timeSlider.addChangeListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent e) {
// time consuming processes ( server call, add image to map, etc)
}
});
I tried to simplify it.
It is much better than before, but I still can not see the data played properly. Sometimes data is played after JSlider ticks. Could it be because my time consuming process is in the second components(JSlider) stateChanged event? Should I use a second SwingWorker in JSlider's event too? Any suggestions about what can I do?
Moreover, what would be the best way to disable all components before playing data, and enable them after playing data?
Thank you very much in advance
If you have two activities Activity A and Activity B which have to be run simultaneously, you need to create a thread for the second activity - the first activity will already be run in its own thread (the main program).
The scheme is as follows:
Program A:
create new Thread: Activity B
run allother tasks for Activity A
In more specific terms the following program will run your simulation and update the tick of the slider:
public P() {
animation.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
doInBackgroundImp();
}
});
setSize(500, 500);
setLayout(new FlowLayout());
add(animation);
add(timeSlider);
setVisible(true);
}
protected void doInBackgroundImp() {
Thread th=new Thread() {
public void run() {
try{
for(int i=0; i<24; i++) {
final int value = i - 48 + 24;
timeSlider.setValue( i );
System.out.println(timeSlider.getValue()+" "+value);
Thread.sleep(1000);
}
} catch(Exception ex) {
ex.printStackTrace();
}
}
};
th.start();
}
private JButton animation = new JButton("");
private JSlider timeSlider = new JSlider();
}

Tray icon simply not showing in java

I've been trying all day to get my tray icon added, but it doesnt work. I have the icon file stored within the netbeans src/myproject/
I have tried a gazillion different paths, even direct ones to my files, but none seem to work. I'm pretty sure something in my code doesnt work, I simply can't see it.
public void createSystemTrayIcon() {
if (SystemTray.isSupported()) {
SystemTray tray = SystemTray.getSystemTray();
Image img = Toolkit.getDefaultToolkit().getImage("smallicon.ico");
PopupMenu popup = new PopupMenu();
final MenuItem menuExit = new MenuItem("Quit");
MouseListener mouseListener =
new MouseListener() {
public void mouseClicked(MouseEvent e) {
show();
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
};
ActionListener exitListener =
new ActionListener() {
public void actionPerformed(ActionEvent e) {
Runtime r = Runtime.getRuntime();
System.out.println("Exiting...");
r.exit(0);
}
};
menuExit.addActionListener(exitListener);
popup.add(menuExit);
final TrayIcon trayIcon = new TrayIcon(img, "ESOLeaderboards", popup);
ActionListener actionListener =
new ActionListener() {
public void actionPerformed(ActionEvent e) {
trayIcon.displayMessage("ESOLeaderboards ","version: EU 1.0",
TrayIcon.MessageType.INFO);
}
};
trayIcon.setImageAutoSize(true);
trayIcon.addActionListener(actionListener);
trayIcon.addMouseListener(mouseListener);
try {
tray.add(trayIcon);
} catch (AWTException e) {
System.err.println("TrayIcon could not be added.");
}
} else {
// System Tray is not supported
}
}
Toolkit.getDefaultToolkit().getImage("smallicon.ico"); supports only JPG, PNG and GIF images.
It doesn't support ico images. Use another image.
In windows 10, I've been able to view a 16 pixels PNG in the tray this way:
final URL resource = getClass().getResource("icon16.png");
final TrayIcon trayIcon = new TrayIcon(Toolkit.getDefaultToolkit().getImage(resource), "Application v0.1 tooltip");
It's "expected" that other OSes would down-scale a big icon, but I haven't tested it.
The standard method of embedding images (and any other non-class resources) is to just put them in a package in the project, e.g. if you project is using com.myproject.myapp, then create a package (just a folder, really) images (under myapp) and put you image files there.
Access to those images (resources) is gained by using the ClassLoader methods getResource(name) and/or getResourceAsStream(name). For simplicity to get the right ClassLoader instance many prefer to also create a class (e.g. "Images") in that same package and define static constants there to access the resources by name (as simple as Images.CONSTANT_NAME). Project structure may look like this:
com.myproject.myapp
images
Images.class
MyImage1.png
In the images class, constants can be defined either for the resource handle or the resources themselves:
public final static URL MY_IMAGE_1 = Images.class.getResource("MyImage1.png");
(The URL could then be passed to Toolkit). If an eager load of everything is desired/feasible the loaded images themselves:
public final static Image MY_IMAGE_1 = loadImage("MyImage1.png");
private static Image loadImage(String name) {
URL url = Images.class.getClassLoader().getResource(name);
Image img = Toolkit.getDefaultToolkit().getImage(url);
// possible hack to force pre-loading of (toolkit) image in next line
// new ImageIcon(img);
return img;
}
Obviously I omitted all error handling from the examples, loading methods should include detailed error handling and reporting (logging/System.out and/or throwing appropiate exceptions) when something goes wrong.
These approaches will work in IDE as well as after creating a jar file for the program.

Java Swing, restore from system tray not working in Linux

I am creating an application in Java and I would like that when you minimize to an icon, the application will have to "hide" in the system tray.
The code I use is this: (the significant part of the code)
myFrame = new JFrame();
myFrame.addWindowListener(new WindowAdapter() {
#Override
public void windowIconified(WindowEvent e) {
PutTray();
}
#Override
public void windowDeiconified(WindowEvent e) {
System.out.println("Deiconified");
}
});
This is a "PutTray" function:
private void PutTray()
{
try
{
tray.add(trayIcon); // Initialized elsewhere
myFrame.setVisible(false);
} catch (AWTException e) {
System.err.println(e);
}
}
To restore (via option in the pop-up menu when you press the icon minimized):
MenuItem show = new MenuItem("Show");
show.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
myFrame.setVisible(true);
myFrame.setState(JFrame.NORMAL);
tray.remove(trayIcon);
}
});
The code works perfectly on Windows 8, but it does not work on Linux (Kali Linux and even Ubuntu).
Why Windows yes and Linux no?
EDIT:
On Linux, after you press the command to show the application, it appears for a very small moment, and then minimizes again. Basically is triggered the event "windowDeiconified" and immediately after the event "windowIconified" without taking the time to do something else and then the application is shown in the system tray.
As Dan Getz suggests, I also thought the order of setVisible and setState should be inverted since the javadoc for setState says:
If the frame is not visible on the
* screen, the events may or may not be
* generated.
but this didn't help.
The one thing that did help though was replacing setVisible(false) with dispose(). They are similar in that you can use setVisible(true) to reopen a disposed window. You can read more about it here: JDialog setVisible(false) vs dispose()
I'll try to find an explanation and come back with it :)
SSCCE to simulate OP problem:
public class Test {
private JFrame myFrame;
public Test() {
myFrame = new JFrame();
myFrame.setVisible(true);
myFrame.setSize(300, 300);
myFrame.addWindowListener(new WindowAdapter() {
#Override
public void windowIconified(WindowEvent e) {
PutTray();
}
});
}
private void PutTray() {
myFrame.setVisible(false); //replace with dispose(); and it's ok
Timer t = new Timer(1000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent actionEvent) {
myFrame.setVisible(true);
}
});
t.setRepeats(false);
t.start();
}
public static void main(String[] args) {
new Test();
}
}
I think you are getting it wrong!
Maybe you are confused about deiconified and visibility
windowIconified()
will be called when we click minimize button
and
windowDeiconified()
is called when we restore it from taskbar and not system tray!
In order to restore from system tray you need to use this
trayIcon.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
window.setVisible(true);
}
});
Basically i don't think the difference between dispose() & setVisible() will bother you in this specific problem
Still, my recommendation is to use setVisible() here

Hows to open an .bmp/.jpeg image using Java

I am working on a JFrame/panel that will contain a button. When the user clicks the button, I want an image (which will be stored in the computer hard disk beforehand) to open on the front screen.
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
//here i want a code that will somehow open the image from a given directory
}});
Any suggestions on how to go about this ? I have to tell where the image is stored and trigger a virtual 'double click' for the image to pop up on the front screen. Is that even possible using java to synchronize such computer functions?
I don't know a very short way, but I would use something like this (as qick hack to get an impression):
try {
// this is a new frame, where the picture should be shown
final JFrame showPictureFrame = new JFrame("Title");
// we will put the picture into this label
JLabel pictureLabel = new JLabel();
/* The following will read the image */
// you should get your picture-path in another way. e.g. with a JFileChooser
String path = "C:\\Users\\Public\\Pictures\\Sample Pictures\\Koala.jpg";
URL url = new File(path).toURI().toURL();
BufferedImage img = ImageIO.read(url);
/* until here */
// add the image as ImageIcon to the label
pictureLabel.setIcon(new ImageIcon(img));
// add the label to the frame
showPictureFrame.add(pictureLabel);
// pack everything (does many stuff. e.g. resizes the frame to fit the image)
showPictureFrame.pack();
//this is how you should open a new Frame or Dialog, but only using showPictureFrame.setVisible(true); would also work.
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
showPictureFrame.setVisible(true);
}
});
} catch (IOException ex) {
System.err.println("Some IOException accured (did you set the right path?): ");
System.err.println(ex.getMessage());
}
I think this will work ...
Code:
process = new ProcessBuilder("mspaint","yourFileName.jpeg").start();
This will open your image file with mspaint.....
and also use *Java Advanced Imaging (JAI)*
Try this code
try
{
// the line that reads the image file
BufferedImage image;
// work with the image here ...
image = ImageIO.read(new File("C://Users//Neo//Desktop//arduino.jpg"));
jLabel1.setIcon(new ImageIcon(image));
}
catch (IOException e)
{
// log the exception
// re-throw if desired
}
I'm not sure but try this...
try
{
JLabel picture=new JLabel();
ImageIcon ic=new ImageIcon(Toolkit.getDefaultToolkit().getImage(getClass().getResource("C:\\Users\\Desktop\\xyz.jpg")));
picture.setIcon(ic);
}
catch(Exception)
{
}

Unable to receive grab event by using GRAB_EVENT_MASK?

I added an AWTEventListener to process grab event. So this listener just use sun.awt.SunToolkit.GRAB_EVENT_MASK
mark.
But This listener can not capture UngrabEvent. The tricky thing is, when a JComboBox popuped its menulist, it can capture this event.
I use the following code for testing.
Start the program, click on the empty area of the frame, click on the frame title. Then there should be an UngrabEvent. But the listener does not capture it.
Start the program, click on the combobox and make its menulist popuped. click on the
frame title. Then there should be an UngrabEvent. And the listener captures it.
It is very strange...Is there any relationship between UngrabEvent and JComboBox?
public class ComboboxLearn {
public static void main(String[] args) {
// TODO Auto-generated method stub
Toolkit toolkit = Toolkit.getDefaultToolkit();
toolkit.addAWTEventListener(new AWTEventListener() {
#Override
public void eventDispatched(AWTEvent event) {
System.out.println(event);
}
}, sun.awt.SunToolkit.GRAB_EVENT_MASK);
JComboBox box = new JComboBox(new Object[] { "AAA", "BBB", "CCC" });
box.addPopupMenuListener(new PopupMenuListener() {
#Override
public void popupMenuCanceled(PopupMenuEvent e) {
System.out.println(e);
}
#Override
public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
System.out.println(e);// Set a breakpoint here
}
#Override
public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
System.out.println(e);
}
});
JFrame f = new JFrame();
f.getContentPane().setLayout(new FlowLayout());
f.getContentPane().add(box);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(new Dimension(100, 100));
f.setVisible(true);
}
}
I sense you're experimenting; but generally, you shouldn't rely on Sun/Oracle's undocumented APIs.
I want a popup that will hide when the
mouse is pressed outside the popup but
not hide when the mouse is pressed on the popup.
Why not bring up a JDialog when you see isPopupTrigger() and hide it when you see it deactivating, as another window activates? The notion is discussed here.
Although trashgod's reasoning is understandable, it doesn't answer the question: What you are actually trying to do won't work because for the grab even to fire, you need to have a window grabbed: ((SunToolkit)Toolkit.getDefaultToolkit()).grab(someWindow);.
You could change your code as follows
class ComboboxLearn {
public static void main(String[] args) {
// TODO Auto-generated method stub
Toolkit toolkit = Toolkit.getDefaultToolkit();
toolkit.addAWTEventListener(new AWTEventListener() {
#Override
public void eventDispatched(AWTEvent event) {
System.out.println(event);
}
}, sun.awt.SunToolkit.GRAB_EVENT_MASK);
JComboBox box = new JComboBox(new Object[] { "AAA", "BBB", "CCC" });
JFrame f = new JFrame();
box.addPopupMenuListener(new PopupMenuListener() {
#Override
public void popupMenuCanceled(PopupMenuEvent e) {
System.out.println(e);
}
#Override
public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
System.out.println(e);// Set a breakpoint here
//UNGRABBING WINDOW
((SunToolkit) toolkit).ungrab(f);
}
#Override
public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
System.out.println(e);
//GRABBING WINDOW
((SunToolkit) toolkit).grab(f);
}
});
f.getContentPane().setLayout(new FlowLayout());
f.getContentPane().add(box);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(new Dimension(100, 100));
f.setVisible(true);
}
}
Then you will get your grab events but at the level you are working on you don't need them.
Then when would I need them?
Assuming you run into this nasty bug which although closed, I could still reproduce it, you need to implement your own popup mechanism. You did everything fine you attached your AWT listeners to close the popup whenever there is a click outside it but something is missing. You click everywhere and the popup disappears except on the window captions and outside your application! Shoot you think! How does JPopupmenu do it. And after you spend some time reading jdk code and trying various stuff, you realize that it's this undocumented event that does the trick.
I don't know the internals of this grab() method and I don't have time to investigate so there might be side effects not very obvious. Call it on your own risk.

Categories

Resources