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Trying To Delay In Java Multiple Times

Need To Do One Animation, Sleep 1000 Then Do The Next Sleep 1000 And So On, Instead It Sleeps For The Entire Time Then Plays All Animations At Once. No Idea What Im Doing.
Tried Timers, Running The Animation Before The tread.sleep And Using A While Loop Instead Of A For.
private void playLaunchAnimation()
{
final Animation animation = AnimationUtils.loadAnimation(this, R.anim.fadein);
for(int i=0; i < buttons.size();i++)
{
try {
Thread.sleep(1000);
buttons.get(i).startAnimation(animation);
} catch (Exception e){
/*
main declares that it throws InterruptedException. This is an exception that sleep throws when another thread interrupts the current thread while sleep is active. Since this application has not defined another thread to cause the interrupt, it doesn't bother to catch InterruptedException.
*/
}
}
}

Hi, Make sure this code helps you
public static void main(String[] args) throws Exception {
for(int i=0; i < 10;i++) {
try {
Thread.sleep(1000);
System.out.println(i);
if(i==9) {
i=0;
}
} catch (Exception e){
System.out.println("error");
}
}
}

(Answer assumes Android which wasn't entirely clear in OP.)
This is somewhat of a lazy way to do it - but maybe get you thinking. It would
be more interesting to have the handler invoke the next handler so only one handler is declared - but that would be a little more work.
private void playLaunchAnimation() {
final Animation animation = AnimationUtils.loadAnimation(this, R.anim.fadein);
for(int i=0; i < buttons.size();i++)
{
// Create a handler on the UI thread to execute after a delay.
// The delay is a function of loop index.
//
// It may be necessary to declare buttons final - but your
// OP did not list where it is defined.
new Handler(Looper.getMainLooper()).postDelayed(new Runnable() {
#Override
public void run() {
buttons.get(i).startAnimation(animation);
}
}, ((i+1)*1000));
}
}
References:
How to call a method after a delay in Android
Android basics: running code in the UI thread

It sounds like you are calling Thread.Sleep from the User Interface thread. This will ultimately result in the entire User Interface freezing up for the duration of the sleep. What you really want is to launch sleep from a background thread.
For example:
AsyncTask.execute(new Runnable() {
#Override
public void run() {
for(int i=0; i < buttons.size();i++)
{
try {
Thread.sleep(1000);
activity.runOnUiThread(new Runnable() {
buttons.get(i).startAnimation(animation);
});
} catch (Exception e){}
}
});
Another way you could do this using post delay:
new android.os.Handler().postDelayed(
new Runnable() {
public void run() {
buttons.get(i).startAnimation(animation);
new android.os.Handler().postDelayed(this, 1000);
}
},
1000);

How to pause program execution without blocking a Timer (Java Swing)?

I have a Timer that shows an animation on the screen when a game event takes place. What I want to do is have the main execution pause until this animation finishes, but everything I try seems to block the Timer from running. I've tried using Thread.sleep() and calling wait() and notify() on a lock object, but with the same result. The Timer listener's actionPerformed() is never called.
This code sets up the timer:
protected void showMovingEffect(int steps, Direction dir, AnimatedImageSet imgs) {
effectsPane.runAnimation(imgs, dir, steps);
waiting = true;
while (waiting) {
synchronized(animationWaitLock) {
try {
animationWaitLock.wait();
} catch (InterruptedException e) {}
}
}
}
And the Timer and listener inside the EffectsPane object:
private void runAnimation(AnimatedImageSet ais, Direction dir, int iters) {
System.out.println("run");
imgs = ais;
top = 0;
left = 0;
topStep = dir.getRowIncrement() * 10;
leftStep = dir.getColIncrement() * 10;
iterations = iters;
index = 0;
active = true;
timer.start();
}
public void actionPerformed(ActionEvent e) {
System.out.println(index);
top += topStep;
left += leftStep;
index++;
currentImage = imgs.getImage(index);
repaint();
if (index == iterations) {
active = false;
timer.stop();
synchronized(animationWaitLock) {
animationWaitLock.notify();
}
waiting = false;
}
}
The System.out.println call at the start of the actionPerformed() is never called, so either the wait() call is also pausing the Timer, or something is blocking it. If I comment out the sleep/wait lines in showMovingEffect(), the animation runs, but the program does not pause.

One approach would be to display a modal dialog while the animation proceeds. As discussed here, user interaction will be foreclosed, but background GUI updates in response to the javax.swing.Timer will continue. You can allow the user to dismiss the dialog at any time, as shown here, but you may want to abandon the animation at that point.
no input from the user is needed.
You can block user interaction without displaying a dialog by entering a SecondaryLoop after the animation starts.
SecondaryLoop loop = Toolkit.getDefaultToolkit()
.getSystemEventQueue().createSecondaryLoop();
timer.start();
loop.enter();
When the animation concludes, exit() the SecondaryLoop:
public void actionPerformed(ActionEvent e) {
…
if (index == iterations) {
timer.stop();
loop.exit ();
…
}
}

You can try this:
timer.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// your code
}
});

Black view when starting new thread

In my android application I want an automatically refresh every 60 seconds. So I tried it like this:
public void refresh_check() {
Thread myThread = new Thread()
{
int counter = 0;
#Override
public void run() {
MyActivity.this.runOnUiThread(new Runnable(){
#Override
public void run() {
while (counter < 60) {
try {
Thread.sleep(1000);
counter += 1;
System.out.println("Counter: " + counter);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
refresh();
}});
super.run();
}
};
myThread.start();
}
This works in the way that it prints the counter into logcat but in my Application I get a black view. refresh() is just a function with a http request, and this works alone, so the mistake has to be in the thread at any place :/ Can someone help?

You are not utilizing the Thread correctly. Running long tasks on the UI thread is just like not using a Thread at all. To accomplish what you need you should do it like this:
public void refresh_check() {
Thread myThread = new Thread()
{
int counter = 0;
#Override
public void run() {
while (counter < 60) {
try {
Thread.sleep(1000);
counter += 1;
System.out.println("Counter: " + counter); //I think this may cause exception, if it does try removing it
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
refresh(); // In refresh(), use TextView.post(runnable) to post update the TextView from outside the UI thread or use handlers
}});
super.run();
};
myThread.start();
}
Also, take a look at AsyncTask class, it enables you to run long tasks outside UI thread (doInBackground()) as well as update UI with the result from (onPostExecute())

display.async and smooth transitions

I have got my custom widget that changes background when hover. It is working nice but I would like to have smooth transition between no background and hover background. It will work with GC.setAlpha(), but:
Display.getDefault().asyncExec(new Runnable() {
public void run() {
for (int i=0;i<255;i++) {
setBG(BGHelper(imgHover,i)); //i - alpha
try {
Thread.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
This code wait until i == 255, but it doesn't display a smooth transition. Why?

This can not work, because as long as you are in your Code SWT will not repaint or change the component.
You should do the work in a separate Thread and call Display.asyncExec for every change.
for (int i = 0; i < 255; i++) {
final int x = i;
Display.getDefault().asyncExec(new Runnable() {
public void run() {
setBG(BGHelper(imgHover,x)); //x - alpha
}
});
try {
Thread.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}

calling a time consuming method from a JButtonActionPerformed

In the following lines of code when Button1 is pressed the Jframe becomes unresponsive till the execution of the encode() method is completed. But I need to update a progress bar in the Jframe displaying the progress.
private void Button1ActionPerformed(java.awt.event.ActionEvent evt) {
try {
if (flagState == 0) {
WavFile.decode(readWavFile, msg.getText(), key.getText().hashCode());
} else if (flagState == 1) {
WavFile.encode(readWavFile, msg.getText(), key.getText().hashCode());
}
} catch (WavFileException | IOException e) {
notes.setText(e.getMessage());
}
}
I thought of doing this
private void Button1ActionPerformed(java.awt.event.ActionEvent evt) {
try {
if (flagState == 0) {
Thread t = new Thread(new Runnable() {
public void run() {
WavFile.decode(readWavFile, msg.getText(), key.getText().hashCode());
}
};)
t.start();
} else if (flagState == 1) {
Thread t = new Thread(new Runnable() {
public void run() {
WavFile.encode(readWavFile, msg.getText(), key.getText().hashCode());
}
};)
t.start();
}
} catch (WavFileException | IOException e) {
notes.setText(e.getMessage());
}
}
and update the progress bar from the encode() method.
But I understand that it will a strong coupling between the modules and i dont want that.
I also dont think that calling a new thread every time is a good idea ( thought of ExecutorService but not sure how to use it).
What should I do to make this into a decent piece code??

Threading is definitely something you have to introduce here. Anything that takes a significant amount of time to complete should not be run in the awt event thread.
Spawning a new thread each time the button is clicked is not inherently a problem. You should consider, though, that it may be possible to spawn many threads doing the same thing before even the first completes. You could use an Executor if you want, but it probably is not necessary.
As for tracking progress, I would add another thread that periodically queries the other thread and updates the progress bar as necessary. Here's how I would structure it:
private void Button1ActionPerformed(java.awt.event.ActionEvent evt) {
disableButton1();
final Thread t;
if (flagState == 0) {
t = new Thread(new Runnable() {
public void run() {
try {
WavFile.decode(readWavFile, msg.getText(), key.getText().hashCode());
} catch (WavFileException | IOException e) {
notes.setText(e.getMessage());
}
}
});
} else if (flagState == 1) {
t = new Thread(new Runnable() {
public void run() {
try {
WavFile.encode(readWavFile, msg.getText(), key.getText().hashCode());
} catch (WavFileException | IOException e) {
notes.setText(e.getMessage());
}
}
});
}
Thread monitor = new Thread(new Runnable() {
public void run() {
try {
while (notComplete(t)) {
setProgressBar(getProgress(t));
Thread.sleep(SLEEP_TIME);
}
t.join();
} finally {
enableButton1();
}
}
});
t.start();
monitor.start();
}

n the following lines of code when Button1 is pressed the Jframe becomes unresponsive till the execution of the encode() method is completed. But I need to update a progress bar in the Jframe displaying the progress.
you have issue with Concurency in Swing, you block the EDT, caused unresponsive GUI, until code ended
have look at SwingWorker for JProgressBar
use most scallable Swing Action instread of ActionListener
use implemented setEnabled() instead of if (flagState == 0) {

Multithreading is what you need, there is no other nice way i can think of don't worry about calling new threads, that's what they are there for, jvm has a thread pool ready to be used, this sort of things runs really good with threads, try it out!
Create a class that extends Runnable, implement the run method or make it call your current method, that should be enough to do this.
Also you could just make it sleep for a short time and check the status each time the sleep time goes out, if the process finished you can continue, if not, back to sleep for another short time, that way you don't have to ask that many times.
I hope it helps.