I'm creating a java program that involves a button that gives a bunch of problems. I'm wondering how can I create a delay between the times a user can click a button (to prevent button spamming). Here is what I tried.
public void ButtonActionPerformed(java.awt.event.ActionEvent evt) {
Thread DelayTHREAD = new Delay();
if(DelayTHREAD.isAlive()) {
/*do nothing*/
}
else {
/*some other code*/
DelayTHREAD.start();
}
}
public static class Delay extends Thread /*Prevents user from spamming buttons*/ {
#Override
public void run() {
try {
Thread.sleep(5000); /*sleeps for the desired delay time*/
}catch(InterruptedException e){
}
}
}
OK so here is the problem, it doesn't matter whether or not the delay thread is started or not, the program still goes on and continues to perform the action performed as if the delay thread never even existed.
Someone please tell me how can I create a delay, so that a user cannot spam button in a program? Thanks :)
You might just create a little method that disables the button for a period of time after the user clicks on it, and then enables it afterward, like so:
static void disable(final AbstractButton b, final long ms) {
b.setEnabled(false);
new SwingWorker() {
#Override protected Object doInBackground() throws Exception {
Thread.sleep(ms);
return null;
}
#Override protected void done() {
b.setEnabled(true);
}
}.execute();
}
Then call it from your actionPerformed method like this:
disable(button, 5000);
Just make sure you call it from the EDT.
Use a SwingTimer to inject a delay between the button click and the activation of the associated action....
import javax.swing.Timer;
/*...*/
private Timer attackTimer;
/*...*/
attackTimer = new Timer(5000, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
// Do attack...
}
});
attackTimer.setRepeats(false);
/*...*/
public void ButtonActionPerformed(java.awt.event.ActionEvent evt) {
// Restart the timer each time the button is clicked...
// In fact, I would disable the button here and re-enable it
// in the timer actionPerformed method...
attackTimer.restart();
}
Related
Having a "next" Button, when I press keyboard enter key with the button selected, the widgetSelected event of the button is being repeatedly called once and once and doing a super fast next. It's exactly the behaviour I want, but only happens with keyboard enter key.
I want to have that behaviour with mouse click when holding the click. When trying to do the same with the mouse click, the behaviour is not the same, it only makes one event call, and when the click is end (UP). How to simulate the same behaviour with the mouse click?
I tried it doing this, but it blocks the UI (can't understand why) and mouseUp is never being called, it blocks forever in the while:
button.addMouseListener(new MouseAdapter() {
boolean mouseDown;
#Override
public void mouseDown(MouseEvent e) {
System.out.println("mouseDown");
mouseDown = true;
Display.getDefault().asyncExec(new Runnable() {
#Override
public void run() {
while (mouseDown) {
System.out.println("Doing next in mouseDown");
next(composite, label_1);
synchronized(this){
try {
wait(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
});
}
#Override
public void mouseUp(MouseEvent e) {
System.out.println("mouseUp");
mouseDown = false;
}
});
The Runnable you give to asyncExec runs in the UI thread. You must never do any sort of wait in the UI thread as that will block the UI until it completes.
So you cannot run a loop like this as it just blocks the UI. Since the loop never returns to the main SWT readAndDispatch loop no UI actions are done.
Instead use the timerExec method of Display to schedule a Runnable to run after a given interval. This runnable should do one step of the action and use timerExec to schedule the next step later.
I remember there was another question a few days ago regarding a long mouse click behaviour but I can't find it anymore. I put this code based on greg-449 solution to use timerExec method, after my failed attempts to use asyncExec in the UI thread. :)
button.addMouseListener(new MouseAdapter() {
boolean mouseDown;
#Override
public void mouseDown(MouseEvent e) {
mouseDown = true;
Display.getCurrent().timerExec(1000, () -> {
if (mouseDown) {
button.notifyListeners(SWT.Selection, new Event());
button.notifyListeners(SWT.MouseDown, new Event());
}
});
}
#Override
public void mouseUp(MouseEvent e) {
mouseDown = false;
}
});
button.addSelectionListener(SelectionListener.widgetSelectedAdapter(
e -> System.out.println("Do next")));
I have some labels that become visible when the letter a is pressed.
private void formKeyPressed(java.awt.event.KeyEvent evt) {
// TODO add your handling code here:
if(evt.getKeyCode()==KeyEvent.VK_A){
jLabel7.setVisible(true);
jLabel8.setVisible(true);
jLabel9.setVisible(true);
myBlink();
}
I have Label8 on a timer myBlink()
public void myBlink()
{
new Timer(1000, new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("begin");
jLabel8.setVisible(false);
jLabel8.setVisible(true);
System.out.println("Timer");
}
}).start();
}
I have placed printlns to see if timer begins and ends and when I press key "a" my output shows begin Timer multiple times but my label does not appear and disappear. What tweak does this code need? What am I missing? Thanks for the extra set of eyes.
This is probably because you call successively setVisible(false) and setVisible(true) which is done too fast to be seen, you should use a variable and modify its value any time the action of the Timer is called as next:
public void myBlink()
{
new Timer(1000, new ActionListener() {
boolean visible = true;
public void actionPerformed(ActionEvent e) {
jLabel8.setVisible(visible = !visible);
}
}).start();
}
I use Swing Application Framework in my program. And I have some long-time work. I use org.jdesktop.application.Task for it. Another programmer wrote two Tasks before I took this project (I can not ask him about the programm). When Tasks are executing user sees progress bar without showing percent complete, but what shows "Wait" message and user can not click to a main window while Task does not ended. It is fine! But I could not find place where ProgressBars was created. May be it is described in some xml-file or property-file?
Also I wrote another Tasks and when they run, progress bar which I created is not displayed or displayed incorrectly. I read about ProgressBar and ProgressMonitor, but it does not help me.
Programm continue to run after someTask.execute(), but I want to it displays ProgressBar, ProgressMonitor or something else and user can not click the main window and window will display correctly. Now window has black "blocks" when user change it.
May be I need use org.jdesktop.application.TaskMonitor. I try to use it as here https://kenai.com/projects/bsaf/sources/main/content/other/bsaf_nb/src/examples/StatusBar.java?rev=235 , but my main window is displayed incorrectly and my ProgressBar is not displayed.
I need to when Task is running program waits it, but user can see ProgressBar, can cancel the operation and can not click to the main window. How can I do it?
Here my code:
public class A{
#Action(name = "ActionName", block = Task.BlockingScope.APPLICATION)
public RequestInfoTask requestInfo() {
RequestInfoTask task = new RequestInfoTask(Application.getInstance());
isSuccessedGetInfo=false;
task.addTaskListener(new TaskListener.Adapter<List<InfoDTO>, Void>() {
#Override
public void succeeded(TaskEvent<List<InfoDTO>> listTaskEvent) {
isSuccessedGetResources=true;
}
});
//Here I want to the program shows ProgressMonitor and user can not click to the main window.
//But small window with message "Progress..." is displayed for several seconds and disappear.
ProgressMonitor monitor = new ProgressMonitor(getMainView(), "Wait! Wait!", "I am working!", 0, 100);
int progress = 0;
monitor.setProgress(progress);
while(!task.isDone()){
monitor.setProgress(progress+=5);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
}
}
monitor.setProgress(100);
//This code must run after "task" finishes.
if(isSuccessedGetInfo){
MyTask2 task2 = new MyTask2(Application.getInstance());
isSuccessedTask2=false;
task2.addTaskListener(new TaskListener.Adapter<Map<?,?>, Void>(){
#Override
public void succeeded(TaskEvent<Map<String, ICredential>> arg0) {
isSuccessedTask2=true;
}
});
//Do something with results of task2.
}
return task;
}
}
public class RequestInfoTask extends Task<List<InfoDTO>, Void> {
public RequestInfoTask(Application application) {
super(application);
}
#Override
protected List<InfoDTO> doInBackground() throws Exception {
List<InfoDTO> result = someLongerLastingMethod();
return result;
}
}
Part of your problem sounds like it comes from not using the EDT correctly. Any long running task needs to be started in it's own thread to keep the GUI responsive and repainting.
Ideally you'd be following a MVC pattern. In that case you place your Progress Bar in the view, your flag (that indicates whether the task should be running still) in the control, and your long running task in in the Model.
From that point, if your model checks periodically if it should stop (Probably at good stopping points), you can reset everything.
Here's an example with MVC:
import java.awt.BorderLayout;
import java.awt.event.*;
import javax.swing.*;
public class ProgressBarDemo{
public static class View extends JPanel{
Controller control;
public JProgressBar progressBar = new JProgressBar(0, 100);
JButton button = new JButton("Start Long Running Task");
public View(Controller controlIn){
super();
this.control = controlIn;
setLayout(new BorderLayout());
button.addActionListener(new ActionListener(){
#Override
public void actionPerformed(ActionEvent e) {
//Toggle between running or not
if(control.isRunning){
control.isRunning = false;
button.setText("Canceling...");
button.setEnabled(false);
} else{
control.isRunning = true;
button.setText("Cancel Long Running Task");
control.startTask();
}
}});
progressBar.setStringPainted(true);
add(progressBar);
add(button, BorderLayout.SOUTH);
}
}
//Communications gateway
public static class Controller{
View view = new View(this);
boolean isRunning = false;
public void updateProgress(final int progress){
SwingUtilities.invokeLater(new Runnable(){
#Override
public void run() {
view.progressBar.setValue(progress);
}});
}
public void reset(){
SwingUtilities.invokeLater(new Runnable(){
#Override
public void run() {
isRunning = false;
view.button.setText("Start Long Running Task");
view.progressBar.setValue(0);
view.button.setEnabled(true);
}});
}
public void startTask(){
LongRunningClass task = new LongRunningClass(this);
new Thread(task).start();
}
}
public static class LongRunningClass implements Runnable{
Controller control;
public LongRunningClass(Controller reference){
this.control = reference;
}
#Override
public void run() {
try {
for(int i = 0; i < 11; i++){
//Monitor the is running flag to see if it should still run
if(control.isRunning == false){
control.reset();
break;
}
control.updateProgress(i * 10);
Thread.sleep(3000);
}
control.reset();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
public static void main(String[] args) throws InterruptedException {
// Create and set up the window.
JFrame frame = new JFrame("LabelDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
// Add content to the window.
frame.add(new Controller().view);
// Display the window.
frame.pack();
frame.setVisible(true);
}
}
I am trying to call a method repeatedly for as long as a button is pressed. But I get an infinite loop. Could anyone help me?
private void jButton6MousePressed(java.awt.event.MouseEvent evt) {
pressed = true;
while(pressed) {
car.accelerator();
}
}
private void jButton6MouseReleased(java.awt.event.MouseEvent evt) {
pressed = false;
}
Thanks.
You get an infinite loop because you have written an infinite loop, you need
JButton.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
car.accelerator();
}
});
If you want it to repeat the action while it's held own this is more difficult, here is an example of how you do that. In short you need to use threads.
I am pretty sure that once pressed is set to true, you never exit the while loop, so the fact that the button isn't being pressed never registers, the program is stuck. The only thing I can think of is using a timer to check periodically the state of the JButton. Alternatively, you can use multi-threading. That is, have PRESSED be a field in thread 1 that is set by the JButton (as you've done), and have the loop in a thread 2, checking on the status of PRESSED in thread 1.
Edit: Whoops, I see that bmorris591 has already suggested multithreading.
Swing thread enters an infinite loop.
You should run your loop in another thread:
private class BooleanHolder{
bool pressed;
};
final BooleanHolder pressed = new BooleanHolder();
private void jButton6MousePressed(java.awt.event.MouseEvent evt) {
presed.pressed=true;
Thread t = new Thread( new Runnable(){
public void run(){
while(pressed.pressed)
{
car.accelerator();
}
}
}
t.start();
}
private void jButton6MouseReleased(java.awt.event.MouseEvent evt) {
pressed.pressed=false;
}
Without knowing what car.accelerator(); does, it's impossible to make a accurate suggestion.
If car.accelerator() is interacting with the UI in any way, you need to be careful, you should never update the UI from any Thread other then the EDT.
Instead, you could use a rapid firing javax.swing.Timer
private Timer accelerateTimer;
//** ... **//
accelerateTimer = new Timer(15, new ActionListener() {
public void actionPerformed() {
car.accelerator();
}
});
accelerateTimer.setRepeats(true);
//** ... **//
public void mousePressed(MouseEvent me) {
accelerateTimer.restart();
}
public void mouseReleased(MouseEvent me) {
accelerateTimer.stop()
}
I have a save button in a JFrame ;on clicking save the 'save' text sets to 'saving....'; I need to set that text as 'saved' after a delay of 10 seconds.How is it possible in java?
Please help...
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
e.printStackTrace();
}
This is what i did...but this wont shows as 'saving' during that delayed time.
If you want to provide the user with visual feedback that something is going on (and maybe give some hint about the progress) then go for JProgressBar and SwingWorker (more details).
If on the other hand you want to have a situation, when user clicks the button and the task is supposed to run in the background (while the user does other things), then I would use the following approach:
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
button.setEnabled(false); // change text if you want
new SwingWorker<Void, Void>() {
#Override
protected Void doInBackground() throws Exception {
// Do the calculations
// Wait if you want
Thread.sleep(1000);
// Dont touch the UI
return null;
}
#Override
protected void done() {
try {
get();
} catch (Exception ignore) {
} finally {
button.setEnabled(true); // restore the text if needed
}
}
}.execute();
}
});
Finally, the initial solution that was using the Swing specific timer:
final JButton button = new JButton("Save");
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// Take somehow care of multiple clicks
button.setText("Saving...");
final Timer t = new Timer(10000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent evt) {
button.setText("Saved");
}
});
t.setRepeats(false);
t.start();
}
});
This question & first 3 answers are heading down the wrong track.
Use a JProgressBar to show something is happening. Set it to indeterminate if the length of the task is not known, but presumably you know how much needs to be saved and how much is currently saved.
Don't block the EDT (Event Dispatch Thread) - the GUI will 'freeze' when that happens. Use a SwingWorker for long running tasks. See Concurrency in Swing for more details.
The best is to use a timer and its method execute with a delay : http://developer.apple.com/library/mac/documentation/java/reference/javase6_api/api/java/util/Timer.html#schedule(java.util.TimerTask, long). Use a timertask to wrap your runnable and that's it.