I want to make a ProgressBar move gradually using a Jbutton. To achieve this I am using a for loop and the method Thread.sleep. The problem is that insted of moving a tiny bit every second (the progress bar) after pressing the button, the program waits until the loop finishes and then does instantly move the progress up. When I take the loop outside of the button listener it works as I want but I really need it to work when pressing the button. Here is the code:
progressBar.setOrientation(SwingConstants.VERTICAL);
progressBar.setMinimum(0);
progressBar.setMaximum(100);
progressBar.setValue(50);
panel1.setLayout(null);
panel1.add(progressBar);
progressBar.setBounds(40,6,100,100);
button1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
int counter = 5;
for (int i = 0; i < 5; i++) {
progressBar.setValue(progressBar.getValue() + counter);
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
throw new RuntimeException(ex);
}
}
}
});
If anyone can help me I will be very grateful!
Your code runs on the Event Dispatcher Thread (EDT). That thread is responsible for handling events, but also for repainting. Because it's just one thread, the repainting only occurs after your method ends.
There are some ways to solve this. In your case, a javax.swing.Timer would probably be easiest. Instead of running the loop in a single method, the button click starts a timer that runs every second. When it's done the timer can cancel itself. A slightly more difficult alternative is to use a SwingWorker. You could publish data in the doInBackGround method, and override process to perform the updates to the progress bar.
For more information, please read Concurrency in Swing.
Related
I am using freeTTS to speak out some text, in the background i want a animated gif to keep playing
When i try this: as soon as the voice starts speaking, the image in background gets hanged even if i keep it in some other JFrame... and after the speech is completed it starts moving. I want it to run properly without pauses.
I am placing a animated gif in a label by importing it to my application and changing the icon to that image in label' properties.
Edit
Here is my code:
private void RandomjBActionPerformed(java.awt.event.ActionEvent evt) {
Voice voice;
voice = voiceManager.getVoice(VOICENAME);
voice.allocate();
voice.speak("Daksh");
}
I am actually using a lot of setVisible, setText, declaration of integers, calculating on them but i have removed them to simplify the code for you to understand. Still it gives the same problem if executed.
The button 'RandomjB' is clicked from another button by the following code:
final Timer timer = new Timer(zad, new ActionListener() {
int tick = 0;
#Override
public void actionPerformed(ActionEvent e) {
System.out.println("Success" + ++tick);
RandomjB.doClick();
final int col = Integer.parseInt(t3.getText());;
if (tick >= col) {
((Timer) e.getSource()).stop();
for(int g=0; g<col; g++){
jButton2.setVisible(true); // Check Button -> Visible
}
}
}
});
timer.setInitialDelay(0);
System.out.format("About to schedule task.%n");
timer.start();
System.out.format("Task scheduled.%n");
It is hard to tell without the code, I however assume that you loop the speech synthesis within the one and only Swing-Thread and therefore block all kind of window updates as long as the speech loop is in progress.
As stated by Shaun Wild: you need to use a second Thread for the speech loop.
You may want to do some research on Threads and Concurrency
These allow two things to operate simultaneously, this is just my assumption.
Assuming that you instantiate some kind of class for the FreeTTS you may want to do something like this
FreeTTSClass tts;
new Thread(new Runnable(){
public void run(){
tts = new FreeTTSClass();
}
}).start();
I was programming a GUI today, which is doing longer calculations when pressing a button. While the calculations are running, I wanted to use intermediate results of the still running calculation and write them to a JLabel. The GUI however, should not be operable by the user before the calculation has finished.
At first I was doing something like this:
(1)
public class GUI extends JFrame {
JLabel label = new JLabel("Status: ");
public GUI(){...}
public void calculate() {
for(int i = 0; i < 10; i++) {
String one = calculationPartOne(i);
label.setText("Status: " + one);
label.repaint(); //*
calculationPartTwo(i);
}
}
}
This did not work, the JLabel would only update after the calculation has finished. I also tried to .repaint() and .validate() all components involved at the line commented *, but it did nothing.
So, after trying and searching Google/StackoOverflow the whole day I finally have a working solution, but I still do not understand why above does not work. I wanted the GUI to block, so naturally I ran the calculation in the same thread. However, calling any methods to repaint the GUI -inbetween- the calculation (making the calculation stop while the GUI is updated) did not work, and I do not understand why. Can someone explain?
In the end, I used the SwingWorker class to do my calculations, and use it's functions to update the JLabel while calculating. However, as I need the GUI to block, I now disable -all- the components before excuting the SwingWorker and have the SwingWorker re-enable all the components after finishing the calculation.
So, I use SwingWorker, to not block the EDT, but then "fake" to block the EDT by disabling everything? This seems really paradox to me.
Here is an outline of what I have now:
public class GUI extends JFrame {
JLabel label = new JLabel("Status: ");
//I didn't use a list, but it works to illustrate it here
List<Component> GUIComponents = ...;
public GUI() {...}
public void calculate() {
SwingWorker<Void, String> worker = new SwingWorker<Void, String>() {
protected Void doInBackground() throws Exception {
for(int i = 0; i < 10; i++) {
String one = calculationPartOne(i);
publish(one);
calculationPartTwo(i); //**
}
}
protected void done() {
setEnableGUI(true);
}
protected void process(List<String> chunk) {
label.setText(chunk.get(chunk.size() - 1));
}
};
setEnableGUI(false);
worker.execute();
}
public void setEnableGUI(boolean e) {
for(Component c : GUIComponents) {
c.setEnabled(e);
}
}
//**
public void calculationPartTwo() {...}
}
This works.
I hope someone can clarify. This solutions feels wrong.
why wrong? the gui thread is for responding to user events only - so you should be doing your heavy lifting in the background - which is what youre doing with a SwingWorker.
also, the best way to prevent a user from changing a componenet is to do exactly that - disable the component before starting the heavu lifting, and enable once its done.
only thing you might want to consider is displaying the results of your calculation in a modal dialog - a JDialog that will pop above the parent window and block it. you could display the intermediate results and progress in this dialog and then once the calculation is done the dialog will close and unblock the UI obscured by it. this will save you fron having to disable all gui components indiviually in a loop and will also give you an option to have a "cancel" button to halt the work immediately.
However, calling any methods to repaint the GUI -inbetween- the calculation (making the calculation stop while the GUI is updated) did not work, and I do not understand why. Can someone explain?
repaint() requests are handled by the RepaintManager and are not done immediately. The RepaintManager basically schedules the repaint. Since repainting is done on the EDT, it can't be done until the EDT is free.
So, I use SwingWorker, to not block the EDT, but then "fake" to block the EDT by disabling everything? This seems really paradox to me.
You can always use an indeterminated JProgressBar. See How to Use Progress Bars.
Or maybe you would prefer to use the Disabled Glass Pane approach.
In some cases you can use:
label.paintImmediately(...);
to force the repainting of a component. But you still have the issue of disabling the GUI so its probably not a solution you should really be using.
I'm having an issue with my GUI when I try to change the color of a button after 2 seconds when its has been clicked. What I want to do is to click on a white square button, then a color comes up, after 2 seconds I want it to return to it's original color (white). How can achieve this?
My code on click:
cards[index].setBackground(cards[index].getTrueColor());
try
{
Thread.sleep(2000);
cards[cardPos.get(0)].setBackground(Color.white);
}
catch(Exception e) {}
So this goes back to color white, but in an instance, doesn't wait to seconds.
Really appreciate a little help here.
Thanks!
This calls for a Timer instead of Thread.sleep. You'll want to set the timer with a delay of 2 seconds, and then have it reset the color of your button. For example, in Swing:
// onButtonClick
final Card card = cards[index];
card.setBackground(card.getTrueColor());
new Timer(2000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// Change color back
card.setBackground(Color.WHITE);
}
}).start();
How to Use Swing Timers
You can use the AsynkTask class in Android. You can use the onPreExecute method to execute the initial task, and then you can wait and change the button color after 2 sec, this can be done in doInBackground method and you can publish the results to UI by calling publish progress method, and finally you can use the onPostExecute method.
http://developer.android.com/reference/android/os/AsyncTask.html
I have problem with refreshing swing components inside Mouse action event handler. Problem is that all jLabels which are changed in this function that their changes are visible after jButton1MouseClicked() is done. Here is my function:
private void jButton1MouseClicked(java.awt.event.MouseEvent evt) {
int cycles = Integer.parseInt(c.settings.get("cycles"));
statusMessageLabel.setText("Data collection in progress...");
for(int i=1;i <= Integer.parseInt(c.settings.get("cycles"));i++) {
jLabelCycle.setText(Integer.toString(i));
//here are some functions which are implementing data collection
if(i < cycles){
int counter = Integer.parseInt(c.settings.get("interval"));
while(counter >= 0){
jLabelTimer.setText(Integer.toString(counter));
try {
Thread.sleep(1000);
} catch (InterruptedException ex) {
Logger.getLogger(AppCView.class.getName()).log(Level.SEVERE, null, ex);
}
counter--;
}
}
}
statusMessageLabel.setText("Data collection has been finished.");
}
Can you please help me ? I really need this changes to be visible immidiaetly because one jLabel visualize counting till next cycle and second one is visualizating actual cycle number. I tried call function repaint() on all jLabels after i changed them but it didnt help.
Thank you all for any help.
In AWT, much like most other GUI systems, all events including repaints are done on a single thread, the AWT Event Dispatch Thread (EDT). You are blocking that thread in the event listener, so the repaint events on the label cannot get through.
I suggest rewriting your code to use use javax.swing.Timer instead of Thread.sleep.
In general, long running operations should be handled on a separate thread. Any operations touching AWT or Swing components should be queued for running on the AWT EDT using java.awt.EventQueue.invokeLater.
This jSlider code causes the application to hang.
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
try {
for(int i=0;i<100;i++)
{
jSlider1.setValue(i);
Thread.sleep(3000);
}
} catch (InterruptedException ex) {
Logger.getLogger(AsdView.class.getName()).log(Level.SEVERE, null, ex);
}
}
thank you guys i am updating the answer
Timer time = new Timer(100, new ActionListener() {
int percent = 0;
#Override
public void actionPerformed(ActionEvent e) {
percent++;
if (percent>100)
percent = 0;
jSlider1.setValue((int)(100*(percent/600.0)));
}
});
time.start();
I am guessing you are trying to do some kind of smooth scroll.
That code freezes because the event thread that handles the window painting, sizing, etc..., is being frozen by you executing Thread.sleep(3000), 100 times.
I would recommend that you use a Swing timer that changes the scroll bar little by little.
i don't know why you put the sleep for 3 secs and that too in for loop of 100
3*100 = 5 mins so it will hang upto 5 mins
remove Thread.sleep(3000);
it will work fine and won't hang
When you say your application 'hangs', that generally means that you have some sort of deadlock that prevents your threads from making progress. Is that what you're observing in your program? The way it's currently written, the current thread of execution will take at least 300 seconds to complete. Is this work being done on the main thread of execution? If so, you may want to consider creating a new Thread to do this work.