Jprogressbar not working - java

I am trying to upload a few files over the network. while uploading it will take an indeterminate time. so wish to display an indeterminate jprogressbar during the upload. The problem, however is that my jprogressbar and upload does not work simultaneously. I tried the upload in a separate thread while keeping the jprogressbar in the EDT. I tried a few different ways. some of them are:
1) implemented Runnable and in run() I uploaded the file. The progressbar was in the EDT all this time. (did not work.)
2) had two separate threads and put both upload and progressbar handling in each. (not working). the code for this is :
Thread oThread = new Thread(new Runnable() {
#Override
public void run()
{
progressBar.setIndeterminate(true);
progressBar.setVisible(true);
progressBar.validate();
}
});
Thread oThread1 = new Thread(new Runnable()
{
#Override
public void run() {
logger.info("Upload result from ***: "+ newport.upload(textbyte, wavbyte,xmlbyte, filename));
}
});
3) then I rewrote the entire thing and tried a different approach using Executor like this:
executor.execute(new Runnable() {
#Override
public void run() {
upload actions
SwingUtilities.invokeLater(new Runnable() {
progBar.setVisible(false);
});
}});
but none of these techniques worked. I am new to this and am wondering if all this has to be done to have a jprogressbar (indeterminate) displayed. I would like to know if there is a simpler and easier way to do this.

You aren't actually setting the value of the progress bar at any point in the code you have posted.
Additionally this looks like a good case for using SwingWorker, it will perform the work on a different thread and then call you back with progress. The good thing being those callbacks happen already on the Swing thread.
This SwingWorker example even includes setting a progress bar:
http://docs.oracle.com/javase/6/docs/api/javax/swing/SwingWorker.html

you must use setValue() for change progressbar
below code example for work with jporgressbar
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
public class Tets {
public static void main(String [] args) {
JFrame frame =new JFrame();
JPanel panel=new JPanel();
JProgressBar bar=new JProgressBar();
bar.setMaximum(100);
bar.setMinimum(0);
panel.add(bar);
frame.getContentPane().add(panel);
frame.pack();
frame.setVisible(true);
for(int i=0;i<100;i++){
bar.setValue(i);
try {
Thread.sleep(100);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
good luck

Related

JProgressBar update and thread scheduling

Hello stack exchangers,
I have a problem with progress bars in java Swing. I think my confusions arise from my poor understanding of threads and the Swing event queue (I don't know much about java Threads, and exactly what is happening on the AWTEventQueue, although I generally understand what multithreading is about).
The context is that a JButton is pressed to start a long calculation. Before the calculation starts, I make a progress bar in a JFrame, which I thought would be painted, but it isn't. The frame appears, but it is just grey. The button, in this example has "clickMe" written on it.
In the "clickMe" action listener, I first make and display a JFrame in a subtask which is "run" (I'm not clear on when this is scheduled TBH). Then, I call doTask() which is running in the same thread as the action listener (which I think is the AWTEventThread??). The doTask() runs, printing out numbers to the Console. Intermixed with the doTask() output are iteration counts of the progressbar (from when the action listener started makeProgressBar()).
So, from the output, it looks like both the progress bar is running and the AWTEventThread, but the value set in the JProgressBar GUI is never updated.
How can I change my code so that the GUI gets updated? I've tried understanding the JProgressBar tutorial and hunted around the web, but I think my problem is more a conceptual understanding of Java Tasks.
This is my code:
package problemclass;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import javax.swing.SwingUtilities;
public class ProblemClass
{
void progressBarButtonClick()
{
JFrame buttonInAFrame = new JFrame();
JPanel buttonInAFramePanel = new JPanel();
JButton clickMe = new JButton("Click me!");
buttonInAFramePanel.add(clickMe);
clickMe.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e)
{
JFrame progBarFrame = makeProgressBar();
doTask();
progBarFrame.dispose();
}
});
buttonInAFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
buttonInAFrame.add(buttonInAFramePanel);
buttonInAFrame.pack();
buttonInAFrame.setVisible(true);
}
private void doTask()
{
for(int i = 0; i < 20000; i++)
{
if (i % 100 == 0)
{
System.out.println("TASK iteration " + i);
try
{
Thread.sleep(1000);
}
catch (InterruptedException e) {}
}
}
}
private JFrame makeProgressBar()
{
JFrame progBarFrame = new JFrame();
JPanel progBarPanel = new JPanel();
JProgressBar progressBar = new JProgressBar();
progBarPanel.add(progressBar);
progressBar.setValue(0);
progressBar.setStringPainted(true);
progressBar.setIndeterminate(true);
new Thread(new Runnable()
{
public void run()
{
for (int i = 0; i <= 100; i++)
{
final int j = i;
System.out.println("Progress Iteration " + j);
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
progressBar.setValue(j);
}
});
try
{
java.lang.Thread.sleep(100);
}
catch(Exception e) { }
}
}
}).start();
progBarFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
progBarFrame.add(progBarPanel);
progBarFrame.pack();
progBarFrame.setVisible(true);
return progBarFrame;
}
public static void main(String[] args)
{
EventQueue.invokeLater(() ->
{
new ProblemClass().progressBarButtonClick();
});
}
}
JFrame progBarFrame = makeProgressBar();
doTask();
Not sure exactly what you are trying to do.
The above code has two loops:
In the makePrgressBar() method you start a Thread and invoke SwingUtilities.invokeLater(…), to update the progress bar, which is correct.
but then in doTack() you start another loop. This time you don't start a Thread so the code is invoked on the EDT and since you use Thread.sleep, the EDT will sleep and the GUI will not repaint itself until the entire loop is finished.
I would suggest you get rid of the doTask() method since I don't know why you need two blocks of code that loop. Or if you really need it, then you also need to use a Thread and invokeLater(…).
Just like you, I recently did some work on progress bars and threading and went nuts until I realized that it is just so simple.In a nutshell this is the code I have when my button is clicked:
// Create 2 threads. One handles your GUI. Other does the task
Thread t1 = new Thread(new Runnable() {
#Override
public void run() {
// code goes here.
//In here I choose to hide the button, display the progress bar
}
});
t1.start();
Thread t2 = new Thread(new Runnable() {
#Override
public void run() {
// code goes here.
//In here I get the task done, then hide the progress bar
}
});
t2.start();
Works like a charm every time. Hope it helps!

Not getting the output as expected in Swing

i know multithreading a bit but not in vast and i think the problem is of multithreading. I am calling a method to set label's text by invoking a new thread and leaving it blank after a specified time. I am getting the desired output every time but not only the place which i am going to show you by my piece of code. I am expecting that message should be set and disappeared after the specified time and the window should be minimized after that time. But what actually happening is when it is going to the other thread main thread execution starts and goes for sleep for 5 sec and the message is not appearing and after 5 sec window is getting minimized without showing the message which i am setting on the label.
(Main thread)
Validation.setMessageOnLabel("Username and password has been copied", jLabel15,1.5F);
try {
Thread.sleep(5000);
} catch (InterruptedException ex) {
Logger.getLogger(PasswordManager.class.getName()).log(Level.SEVERE, null, ex);
}
setState(ICONIFIED);
validation.java (setMessageOnLabel())
static public void setMessageOnLabel(final String msg, final JLabel label, final float time)
{
new Thread(new Runnable() {
#Override
public void run() {
label.setText(msg);
try {
Thread.sleep((long) (time*1000));
} catch (InterruptedException ex) {
Logger.getLogger(PasswordManager.class.getName()).log(Level.SEVERE, null, ex);
}
label.setText("");
}
}).start();
}
Since you're calling setState() directly, I assume the first code snippet is part of a JFrame. In that case you're most probably sending the event dispatch thread to sleep for 5 seconds and thus prevent screen updates during that time.
Put the sleep into another thread or use a swing worker instead and call setState() on the EDT in the worker's callback method, since setState() is not labelled as thread-safe and calling it on a thread other than the EDT might result in unexpected behavior.
From the linked tutorial:
Some Swing component methods are labelled "thread safe" in the API specification; these can be safely invoked from any thread. All other Swing component methods must be invoked from the event dispatch thread. Programs that ignore this rule may function correctly most of the time, but are subject to unpredictable errors that are difficult to reproduce.
Don't use Thread.sleep(5000);, that block EDT.
For that purposes you can use swing Timer, examine next example:
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.Timer;
public class TestFrame extends JFrame {
private JLabel lbl;
public TestFrame() {
init();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
setLocationRelativeTo(null);
setVisible(true);
}
private void init() {
lbl = new JLabel(" ");
JButton setText = new JButton("setText");
setText.addActionListener(getActionListener());
add(lbl);
add(setText,BorderLayout.SOUTH);
}
private ActionListener getActionListener() {
return new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
lbl.setText("wait...");
Timer t = new Timer(5000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
lbl.setText("");
setState(JFrame.ICONIFIED);
}
});
t.setRepeats(false);
t.start();
}
};
}
public static void main(String args[]) {
new TestFrame();
}
}
When dealing with Swing components you shuld not use threads like that. Launch your own SwingWorker instead.
public class MySwingWorker extends SwingWorker<Object, Object> {
#Override
public Object doInBackground() {
//your code here
//dont forget to repaint changed component or validate parent of it,
//if your text dont shows up.
return null;
}
}
you can also execute your own runnable via SwingUtilites
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
//again your code here...
}
});

Log during methodeGUI java

I wrote a java program and made a GUI (my first one jeej).
This is my main methode:
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
ui frame = new ui();
frame.setVisible(true);
} catch (Exception e) {
ui.log("Something went wrong: " + e.getMessage());
}
}
});
}
The methode ui.log let's me write to a textArea.
My gui has one button which starts a pretty long methode which takes several minutes to complete.
In this long methode I want to be able to log to my textArea using ui.log().
It works, but It is only displayed when the methode ends and I want to see the results while the methode is running.
Both the button and the buttonEvent listener are made inside new ui();
JButton btnNewButton = new JButton("button1");
btnNewButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
thveryLongMethodeThatIwantToLogDuringExecution();
}
});
Does anyone knows how I can log while the methode is running?
EDIT: I think it has something to do with threads but I'm not sure. I never done something with threads.
Don't perform your work on the EDT. Use the javax.swing.SwingWorker to run time-consuming background tasks.

Show / update components before process finished

I currently have a java program with swing gui that lets the user choose various files (xsl-fo and xml) and generates PDFs using Render X. I have trying for a while to get a pop up JFrame to appear when a button is pressed, which would then show a progress bar, or label to keep the user informed of the progress. However when instantiating a new frame it will appear black, or without components, which then show after the processes have completed.
private void RunButtonActionPerformed(java.awt.event.ActionEvent evt) {
ExecutorService executor = Executors.newFixedThreadPool(8);
//for reach file to process)
for (int i = 0; i < count; i++) {
Runnable worker = new ProcessThreader(conf, i);
executor.execute(worker);
}
executor.shutdown();
JFrame PercentageFrame = new JFrame();
PercentageFrame.setVisible(true);
PercentageFrame.setSize(200, 200);
PercentageFrame.repaint();
while (!executor.isTerminated()) {
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
NarrowOptionPane.errorMessage("Interrupted: ", ex.getMessage());
}
}
System.out.println("Complete");
}
The run button is located in a JPanel, which is located in a JFrame and the Main Frame is instantiated in the main method, and wrapped in the invoke later method
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new MainFrame("PDF Producer");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.setSize(710, 530);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
}
});
}
I'm fairly new to threading / executors and java swing, so go easy! Thanks
Code executed from within a listener is executed on the Event Dispatch Thread. So the Thread.sleep() is causing the EDT to sleep which means the GUI can't respond to events or repaint itself.
Read the section from the Swing tutorial on Concurrency In Swing for more information. One solution as described in the tutorial is to use a SwingWorker for the long running task and to publish results as they become available.
Your while loop block EDT, delete that and your code will be work.
See next example with ExecutorService and JProgressBar :
import java.awt.BorderLayout;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
public class Example extends JFrame {
private static JProgressBar progress;
public static void main(String[] args) {
final JFrame f = new JFrame();
progress = new JProgressBar();
progress.setStringPainted(true);
progress.setIndeterminate(true);
ExecutorService newCachedThreadPool = Executors.newFixedThreadPool(1);
for( int i =0; i<10;i++){
final int j = i;
Runnable r = new Runnable() {
#Override
public void run() {
progress.setString(j+"");
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
newCachedThreadPool.submit(r);
}
f.getContentPane().add(progress,BorderLayout.CENTER);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.pack();
f.setVisible(true);
}
}
Here JFrame show number of Runnable which executed in ExecutorService. Also if you need to get result from your Runnables, try to use Callable instead of Runnable. With that when you submit Callable you get Future instance from which you can get result.
Read about Executors, Callable and Future.

How do I make a thread wait for JFrame to close in Java?

When the program starts, a new JFrame is created. Once the user clicks the start button a thread is created and started. Part of this threads execution is to validate the data on the form and then execute with that data. Once the data has been validated the thread calls dispose() on the original frame and then creates a new JFrame that acts as a control panel.
There is also an automatic mode of the program that doesn't display any GUI at all, this mode reads data from a configuration file and then starts the execution thread and runs everything but without the control panel.
I want the program to end once the thread completes, but in GUI mode, only if the user has closed the control panel as well.
Is it possible to make the thread wait for the frame to close. I assuming that the frame is run from it's own Thread? or is that not the case.
Thanks.
The answer you chose is a little awkward. Using Thread.sleep(1000) will check for window state every second. It is not a performance issue, but just bad coding style. And you may have a one second response time.
This code is a little bit better.
private static Object lock = new Object();
private static JFrame frame = new JFrame();
/**
* #param args
*/
public static void main(String[] args) {
frame.setSize(300, 300);
frame.setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
frame.setVisible(true);
Thread t = new Thread() {
public void run() {
synchronized(lock) {
while (frame.isVisible())
try {
lock.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Working now");
}
}
};
t.start();
frame.addWindowListener(new WindowAdapter() {
#Override
public void windowClosing(WindowEvent arg0) {
synchronized (lock) {
frame.setVisible(false);
lock.notify();
}
}
});
t.join();
}
You can make reference from your thread to the JFrame. Then set the default close operation of JFrame to HIDE_ON_CLOSE. If the JFrame is closed, you can stop the thread.
Example code:
import java.awt.Dimension;
import javax.swing.JFrame;
public class FrameExample extends JFrame {
public FrameExample() {
setSize(new Dimension(100, 100));
setDefaultCloseOperation(HIDE_ON_CLOSE);
setVisible(true);
}
private static class T implements Runnable {
private FrameExample e;
public T(FrameExample e) {
this.e = e;
}
#Override
public void run() {
while (true) {
if (e.isVisible()) {
// do the validation
System.out.println("validation");
try {
Thread.sleep(1000);
} catch (InterruptedException e1) {
break;
}
}
}
}
}
public static void main(String[] args) {
FrameExample frameExample = new FrameExample();
new Thread(new T(frameExample)).start();
}
}
All Swing components, including JFrame, are managed by a single thread, called the Event Dispatch Thread, or EDT. (It's possible to call methods on Swing objects from other threads, but this is usually unsafe, except in a few cases not relevant here.)
You'll probably accomplish what you want here by putting the data validation and execution code in its own object which is otherwise completely unaware of the outside world. Then, call it from one of two other objects: one that manages a GUI, and another that runs in "automatic mode".

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