public void playPanel() throws IOException{
for(int i = 0; i<listData.size(); i++){
try {
Thread.sleep(1000L);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
ascii.setText(listData.get(i));
}
}
What I'm trying to do is play through the listData ArrayList type, which was copied from the ascii JTextArea. Its supposed to be an animation, so when they hit play the function displays the first slide, waits a second, then the next slide, etc.
When I run this the only thing that happens is a pause with nothing on the screen changing until it displays only the final slide. I'm not sure what's wrong with it
You should never call Thread.sleep(...) on the Swing event thread unless your goal is to put the entire application to sleep, rendering it useless. Instead, get rid of the for loop, and "loop" using a Swing Timer. Something like this should work, or be close to a functioning solution (caveat: code has not been compiled nor tested):
int delay = 1000;
new Timer(delay, new ActionListener() {
private int i = 0;
#Override
public void actionPerformed(ActionEvent e) {
if (i < listData.size()) {
ascii.setText(listData.get(i));
} else {
((Timer) e.getSource()).stop();
}
i++;
}
}).start();
Related
The problem that I have in my code is that when it runs the button.setVisible(true); it won't set the button to visible until all the other if statements are passed through which really confuses me.
I'm trying to make simon says, and what this try-catch does is that it makes the button in the sequence order blink so that the user can know which button it is that follows.
I'm new to programming so any tips and advises are welcome.
Thank you for taking a look!
try {
inputOrder.clear();
// System.out.println("THIS IS INPUT" + inputOrder);
Sequence.add(randomNumber());
int f = 0;
for (; f < Sequence.size(); f++) {
//Thread.sleep(2000);
if (Sequence.get(f) == 1) {
try {`
btnNewButton.setVisible(false);
Thread.sleep(1000);
} catch (InterruptedException e1) {
}
Thread.sleep(1000);
System.out.println("it ran here");
btnNewButton.setVisible(true);
}
if (Sequence.get(f) == 2) {
try {
btnBlue.setVisible(false);
Thread.sleep(1000);
} catch (InterruptedException e1) {
}Thread.sleep(1000);
System.out.println("it ran here");
btnBlue.setVisible(true);
}
if (Sequence.get(f) == 3) {
try {
btnYellow.setVisible(false);
Thread.sleep(1000);
} catch (InterruptedException e1) {
}Thread.sleep(1000);
System.out.println("it ran here");
btnYellow.setVisible(true);
}
if (Sequence.get(f) == 4) {
try {
btnGreen.setVisible(false);
Thread.sleep(1000);
} catch (InterruptedException e1) {
}
Thread.sleep(1000);
System.out.println("it ran here");
btnGreen.setVisible(true);
}
System.out.println(Sequence);
// Order.add(getColor(Sequence.get(f)));
System.out.println(Order);
text.setText(String.valueOf(Order.size()));
}
btnNextRound.setVisible(false);
} catch (InterruptedException e1) {
e1.printStackTrace();
}
Looks like this happens because you are doing this operation in the UI thread, and it does not have time to execute EventQueue since you force to sleep the UI thread, due to this thread gets chance to actually do the paint once it finish all the sleep calls.
In order to get desired output, I think you should move the sleep logic into a separate thread or to a SwingWorker. If you moved the logic to a separate thread you need to use the EventQueue.InvokeLater to enable buttons.
The way that the Java Swing GUI works is that everything happens one after another. Only when the entire method you posted is finished will the next GUI events (such as the repainting events that need to occur to show that the button's not visible anymore). Doing a Thread.sleep just makes your method take longer to finish. The result is that your UI is frozen because no other events (such as mouse, keyboard, or repainting events) are able to run until after all of your sleep calls.
To perform animation in Java, you should use the javax.swing.Timer class rather than using Thread.sleep. Below I've posted a quick example of a timer that, when started, will cause a button to flash. This doesn't completely solve your problem (you're also looping, but you really need another timer to actually schedule when the buttons will flash so that they don't all happen at once).
import javax.swing.Timer
/**
* Timer that causes a button to flash (become invisible for 1 second, and then become visible again).
*/
public class ButtonFlashTimer extends Timer {
private final JButton buttonToFlash;
public ButtonFlashTimer(JButton button) {
super(1000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// This method is called every 1000 ms (until we tell
// it to stop). This allows us to perform the next "step"
// in the animation.
boolean isVisible = buttonToFlash.isVisible();
if (isVisible) {
buttonToFlash.setVisible(false);
} else {
buttonToFlash.setVisible(true);
// Once we've flashed, stop the timer (don't keep flashing).
stop();
}
}
});
buttonToFlash = button;
// Become invisible immediately; the 1000 ms will be the time between the first
// call to the actionPerformed (which will set it as invisible) and the second
// call (which makes it visible again).
setInitialDelay(0);
setRepeats(true);
}
}
I am attempting to make an application that retrieves images and .mp3 files and transitions from one image to the next once the audio has finished. The underlying framework of how I transition between these images is a little convoluted, but I have managed to get an action in SWT that successfully enables me to manually transition from one to the next. However, a problem has arisen when I've tried to automate it; when placed into a loop, my playAudio() method begins before all of the calls I make in my displayShow() method have resolved, which results in a blank window, despite the audio still playing.
Here is the run method for the action that I want to start the show:
Action startAction = new Action("Start") {
public void run() {
//do {
displayShow();
playAudio();
//} while(true);
}
};
Here is playAudio(). I am able to PLAY the audio without incident:
public void playAudio() {
final String audio = "Happy_Birthday.mp3";
audioLatch = new CountDownLatch(1);
audioThread = new Thread() {
public void run() {
try {
Player player = new Player
(new BufferedInputStream
(new FileInputStream(audio)));
player.play();
audioLatch.countDown();
} catch (JavaLayerException e) {
} catch (FileNotFoundException e) {
} catch (Exception e) {
}
}
};
audioThread.start();
try {
audioLatch.await();
} catch (InterruptedException e) {
}
}
And here is displayShow():
private void displayShow() {
new Thread() {
public void run() {
Display.getDefault().asyncExec(new Runnable() {
public void run() {
Control[] children = container.getChildren();
for (int i = 0; i < children.length; i++) {
children[i].dispose();
}
show.showSlide(container);
container.layout();
}
});
}
}.start();
}
show.showSlide returns a composite whose parent is container, which is the immediate child of the highest parent composite. Within the newly created composite, an image is added to a label and the label's parent is assigned to composite. I realize whether displayShow() is in a separate thread or not seems to be immaterial; this was just the last thing I tried.
It is not solely the addition of the loop that causes the refresh to not execute. The only way I can get the manual transition to work is if I remove the CountDownLatch from the playAudio() method. Were I to remove this latch, the only way to encase these two methods in a loop would be embedded while loops, which seem to hog a fair amount of the CPU and still does not solve my problem. Am I missing anything?
The audioLatch.await() is blocking the main program thread, this is the thread that all SWT operations run on so the Display.asyncExec runnables are just being queued until the thread is available.
If you really must wait in the playAudio method you could run the display event loop there until the background thread is finished:
while (! background thread finished)
{
if (!display.readAndDispatch())
display.sleep();
}
I want to display different images in a same frame within a loop. String pathName[] contains the different paths of the images. When running this code, only last image i.e image at path pathname[last] is getting displayed on frame instead I want all images to be displayed in a continuous way (have given delay of 1sec ). Help is appreciated.
public void actionPerformed(ActionEvent event) {
int i=0;
while(i<5){
if(i>0){
Container labelParent = receiverImageLabel.getParent();
labelParent.remove(receiverImageLabel);
labelParent.validate();
labelParent.repaint();
}
try {
imageR = ImageIO.read(new File(pathName[i++])).getScaledInstance(512,512 , BufferedImage.SCALE_SMOOTH);
receivedImage = new ImageIcon(imageR);
}catch (IOException e) {
e.printStackTrace();
}
receiverImageLabel = new JLabel(receivedImage);
receiverFrame.getContentPane().add(BorderLayout.EAST,receiverImageLabel);
receiverFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
receiverFrame.setSize(800,700);
receiverFrame.setVisible(true);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
Your problem is a common one: you're calling Thread.sleep(...) in a Swing GUI on the event thread and are essentially thus putting the entire GUI to sleep.
Solution: Google the Swing Timer and use this in place of your while loop/Thread.sleep(...)
Also, if the images aren't too big, then consider reading them all in at once (in a background thread), putting them into ImageIcons, and then swapping out a JLabel's ImageIconsand in your Swing Timer.
For example, you could do something like:
ImageIcon[] icons = new ImageIcon[IMAGE_COUNT];
for (int i = 0; i < IMAGE_COUNT; i++) {
BufferedImage img = ImageIO.read(...); // read in the appropriate image
// ...... here manipulate the image if desired such as re-size it
icons[i] = new ImageIcon(img); // put it into an icon
}
elsewhere:
int timerDelay = 1000;
new Timer(timerDelay, new ActionListener(){
int count = 0;
#Override
public void actionPerformed(ActionEvent e) {
if (count < IMAGE_COUNT) {
someLabel.setIcon(icons[count]);
count++;
} else {
// stop the timer
((Timer)e.getSource()).stop();
}
}
}).start();
Note: code not compiled nor tested and is posted only as a general example of steps to consider.
On button click I am calling following function.
private void badButtonHandler() {
Camera.Parameters params = mCamera.getParameters();
params.setColorEffect(Camera.Parameters.EFFECT_NEGATIVE);
mCamera.setParameters(params);
if(thread != null){
thread = null;
}
thread = new Thread()
{
#Override
public void run() {
try {
while(true) {
sleep(5000);
Camera.Parameters params = mCamera.getParameters();
params.setColorEffect(Camera.Parameters.EFFECT_NONE);
mCamera.setParameters(params);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
thread.start();
}
This function is intended to change the Color Effect of Camera after 5 seconds of button click. When pressing the related button for the first time it behaves as expected. But additional calls to this function do not behave as expected. I.e., the second time it waits for 2 seconds, after which it decreases to lower values with every click.
You should not be relying on sleep() as an accurate timer. It won't automatically wake up at the designated time and become the currently active thread, because of the simple fact that all threads are at the mercy of the thread scheduler. Which undoubtedly will vary from OS to OS based on the given JVM.
I have always relied on custom timer functions for these types of scenarios. So, for example:
myTimer(System.nanoTime());
public static void myTimer(long startTime) {
while (startTime + 5000000000 > System.nanoTime()) { //Wait for 5 seconds
try {
Thread.sleep(50); //Sleep at ~50 millisecond intervals
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
}
You won't need to create an entirely new thread as you have done in your example, since Thread.sleep() will put the current thread to sleep. Also, using a while(true) loop is just poor programming practice.
Using nanoTime() is preferred since it is the most precise system timer available in Java.
See this documentation for additional info on the unreliability of the sleep() function.
try this
Thread timer = new Thread(new Runnable() {
#Override
public void run() {
// TODO Auto-generated method stub
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
//Your desired work
}
}
});
timer.start();
private class MultipleGensListener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
for(int i = 0; i < 25; i++)
{
game.runSimulationOneGen();
changeGrid();
}
}
}
//this is the loop. The changeGrid method displays a game grid on a GUI but
// only the 25th iteration is visible on screen. I would like each one to be
// visible for about a half a second before the loop continues.
// I have seen some questions answered on here that are very close to what I'm asking,
// but I just don't really understand how to apply it to my program..
// thanks for any help.
If the code performed by the simulation is quick and does not consume too much CPU and time, then consider using a Swing Timer to do your looping and delay. Otherwise, you'll need to use a background thread such as can be done with a SwingWorker object.
For e.g. if using both Swing Timer and SwingWorker:
private class MultipleGensListener implements ActionListener {
protected static final int MAX_INDEX = 25;
public void actionPerformed(ActionEvent e) {
int timerDelay = 500; // ms delay
new Timer(timerDelay, new ActionListener() {
int index = 0;
public void actionPerformed(ActionEvent e) {
if (index < MAX_INDEX) { // loop only MAX_INDEX times
index++;
// create the SwingWorker and execute it
new SwingWorker<Void, Void>() {
#Override
protected Void doInBackground() throws Exception {
game.runSimulationOneGen(); // this is done in background thread.
return null;
}
#Override
protected void done() {
changeGrid(); // this is called on EDT after background thread done.
}
}.execute(); // execute the SwingWorker
} else {
((Timer) e.getSource()).stop(); // stop the timer
}
}
}).start(); // start the Swing timer
}
}
NEVER BLOCK THE GUI EVENT THREAD
you can use a timer for that and have it only fire 25 times
final Timer t = new Timer(500,null);
t.addActionListener(new ActionListener(){
int i=0;
public void actionPerformed(ActionEvent e){
game.runSimulationOneGen();//run 1 iteration per tick
changeGrid();
if(i>25){t.stop();}
i++;
}
});
t.setRepeats(true);
t.start();
btw the reason only the last iteration is shown is that gui updates (redraws) are done in a separate event, but to let another event trigger you need to return from the listener method which you didn't
the Timer I showed is a more elaborate iteration which lets other events run in between iterations allowing the gui to show the changes
check my post that shows both methods java.swing.Timer#setDelay(int)
and
correct usage of Thread.sleep(int)
java wait cursor display problem