How to stop the timer function after the object has been shot? - java

I am making a simple target shooting game.I have a countdownTimer inside the label and an object that blinks in a random position inside the panel. Every time I click on the object,. the object's timer stops which makes that object stop too, but the countdown timer doesn't and that is my problem. I want the countdown timer should stop also.
Could someone help me about this matter?
Here's the code :
private void starting()
{
new Timer(TIMER_PERIOD, new ActionListener()
{
#Override
public void actionPerformed(ActionEvent e)
{
if (count++ < MAX_COUNT)
{
String text = "Time remaining: (" + (MAX_COUNT - count) + ") seconds left";
setCountDownLabelText(text);
Date date = new Date();
setCountDownPanelText(date);
}
else
{
((Timer) e.getSource()).stop();
randomTimer.stop();
JOptionPane.showMessageDialog(null, "Game Over");
System.exit(0);
}
}
}).start();
}

It strikes me that you don't understand the code at all, that you are unaware of the anonymous class created that is extending Timer, which (if you'd seen the documentation) has a function stop() which does what you ask.
You need to store a reference to the Timer.
private javax.swing.Timer timer;
private void starting() {
timer = new Timer(TIMER_PERIOD, new ActionListener()
{
#Override
public void actionPerformed(ActionEvent e)
{
// do stuff
// stop the timer
timer.stop();
// do other stuff
}
}
}

Related

Java Timer object error: Timer already cancelled

I have a JButton that starts a countdown timer when pressed. When I press the button, it begins, and when I press it again (Button will say "Stop"), it stops. However when I press it again to start the time again I get an error saying:
Exception in thread "AWT-EventQueue-0" java.lang.IllegalStateException: Timer already cancelled.
Here is my code:
final static Timer t = new Timer();
static void startTimer(JButton b) {
t = new Timer(); // Solved: I needed to create a new Timer object.
t.scheduleAtFixedRate(new TimerTask() {
double timeleft = calcShutterSpeed;
#Override
public void run() {
String s = secondsToMinutes(timeleft);
time.setText(s);
timeleft--;
if (timeleft < 0) {
t.cancel();
b.setText("START TIMER");
b.setForeground(Color.BLACK);
}
}
}, 0, 1000);
}
static void stopTimer() {
t.cancel();
}
/**
* Creates the timer if "Start" is pressed.
*
* #param b
*/
static void timer(JButton b) {
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// If start button is pressed, change text to display stop
if (b.getText() == "START TIMER") {
startTimer(b);
b.setText("STOP TIMER");
b.setForeground(Color.RED);
}
// If stop button is pressed, cancel timer and change text to start
else if (b.getText() == "STOP TIMER") {
stopTimer();
b.setText("START TIMER");
b.setForeground(Color.BLACK);
}
}
});
}
Any tips or suggestions that can fix this problem would be much appreciated. Thanks in advance!
EDIT: Really really simple fix for the curious. The fix is in the code.
I think that the "cancel" method on timer still keeps scheduled task with a cancel status.
The call to "purge" method, directly after the cancel should clean the queue and maybe solve this issue.

Stopping Java timer

new Timer(1000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
timeout--;
if(timeout>=1){
status1.setText("Time out: " + timeout);
}else{
patient1.setText("Patient: ");
status1.setText("Status: Available");
doctor.get(0).setStatus(true);
countDoc++;
setDoc.setText(avDoc + countDoc);
timeout = 24;
}
}
}).start();
How to stop this piece of timer at the end of the else statement? I really scratched my head for this and searched almost everywhere
If you're trying to stop the Timer from within its ActionListener, then you can get the reference to the Timer object from the ActionEvent's getSource() method, and then stop it by calling stop() on the reference:
((timer) e.getSource()).stop();
or to break it down:
// assuming an ActionEvent variable named e
Timer timer = (Timer) e.getSource();
timer.stop();
and in context:
public void actionPerformed(ActionEvent e) {
timeout--;
if(timeout>=1){
status1.setText("Time out: " + timeout);
}else{
patient1.setText("Patient: ");
status1.setText("Status: Available");
doctor.get(0).setStatus(true);
countDoc++;
setDoc.setText(avDoc + countDoc);
timeout = 24;
((timer) e.getSource()).stop();
}
}
define the timer first as in:
Timer tim = new Timer(......)
tim.start();
tim.stop();
this will allow you yo stop the timer anywhere (providing you make it global)
you can also change it's attributes easily if you tie it to a var rather than creating an object like that..

Thread.sleep() to swing Timer conversion

I am trying to implement a Thread.sleep(6000) line but it seems to freeze in the applet. When I tried to use Timers, I wasn't sure how to use because I am not very good with event listeners. I am basically trying to call a method fetchUrl() every 6 seconds, after the user clicks the enter button. How can I implement this?
public void init() {
c = getContentPane();
c.setLayout(flow);
c.setBackground(forum);
question.setForeground(Color.white);
question.setFont(tnr);
question2.setForeground(Color.white);
question2.setFont(tnr);
result.setForeground(Color.white);
result.setFont(tnr);
resp.setBorder(BorderFactory.createBevelBorder(0));
timeLength.setBorder(BorderFactory.createBevelBorder(0));
c.add(question);
c.add(resp);
c.add(question2);
c.add(timeLength);
c.add(enter);
c.add(result);
resp.requestFocus();
enter.addActionListener(this);
t = new Timer(DELAY, this);
t.setInitialDelay(DELAY);
}
public void actionPerformed(ActionEvent e) {
final String n1;
int timeMin, timeSec, count = 0, maxCount;
timeMin = Integer.parseInt(timeLength.getText());
timeSec = timeMin * 60;
maxCount = (int)(timeSec/6);
if (e.getSource() == enter) { //user clicks enter
n1 = resp.getText();
while (count < maxCount) {
fetchUrl(n1); //this method called every 6 seconds
t.start();
count++;
}
}
}
First I would start by separating the ActionListener for the Timer and for the JButton.
Second nothing is happening logically with the Timer because you're swallowing it with the button source check.
Third you should understand how the timer works. Basically for every "tick" (in your case six seconds) the actionPerformed of the timer ActionListener is called. So if you want the fetch() method called, then that's what you should be visible/accessible to the in the Timer's actionPerformed.
The button's ActionListener should only handle the starting of the timer I believe. So just separate the listeners. Give each one an anonymous ActionListener and no need to make the class implement ActionListener.
For example
timer = new Timer(DELAY, new ActionListener(){
public void actionPerformed(ActionEvent e) {
// do some stuff every six seconds
fetchURL();
}
});
enter = new JButton(...);
enter.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
timer.start();
}
});
If you want some automatic stopping feature for the timer, you could do something like
timer = new Timer(DELAY, new ActionListener(){
public void actionPerformed(ActionEvent e) {
if (someStoppingCondition()) {
timer.stop();
} else {
// do some stuff every six seconds
fetchURL();
}
// do some stuff every six second
}
});
You need to call a method after user clicks on button every 6 seconds, but you have not said how many times you want to call it.
For infinite number of times, try something like the following,
while(true){
new Thread(){
#Override
public void run(){
try{
Thread.sleep(6000);
fetchUrl(n1);
}catch(InterruptedException e){}
}
}.start();
}
If you will use Thread.sleep() in your applet, then your applet will be hanged for 6 seconds and so create a new thread for it.

How stop object in TimerTask?

I have 6 objects in the class GUI which are moving through the code:
Anim anim = new Anim();
Timer timer = new Timer();
timer.scheduleAtFixedRate(anim, 30, 30);
When an object comes to a point I want to stop it. In class Anim I'm doing:
public class Anim extends TimerTask {
#Override
public void run() {
if (t1.x == 300 && t1.y == 300) {
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
It stops application, and I want have stayed at a concrete object. How to do it?
EDIT:
Ok, now it works well, does not interfere with other objects. But the object is moving on and after 1 second back to the starting position. I wish the whole time he was in the same position when a sleep.
if (Main.auto1.x == 700 && Main.auto1.y == 350) {
timer = new javax.swing.Timer(1000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
Main.auto1.x = 700;
Main.auto1.y = 350;
}
});
timer.setRepeats(false);
timer.start();
Use Swing Timer instead of Thread.sleep() and Java Timer in a Swing application that sometime hangs the Swing applicaion.
Read more How to Use Swing Timers
Sample code:
private Timer timer;
...
timer = new javax.swing.Timer(3000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
//do what ever you want to do
// call timer.stop() when the condition is matched
}
});
timer.setRepeats(true);
timer.start();
EDIT
Please have a look at my another post How to fix animation lags in Java?

How to display a Swing timer's remaining time in one second intervals?

I've been working on a simple game using a Java Applet in which the player's goal is to get as many points as possible within a 30 second timeframe. Right now, I'm using a Swing timer to count down from 30 seconds, and once the 0 mark is reached, a "game over" screen is displayed with the player's score. I have these instance variables:
ActionListener listener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
screenState = 0;
repaint();
}
};
Timer displayTimer = new Timer(30000, listener);
When the player clicks the "play" button, I execute displayTimer.start();.
Then, I have this within the appropriate case in my paint class:
g.drawString("Time Remaining: " + displayTimer.getDelay()/1000, 650, 100);
So, obviously, right now it's just displaying a static "Time Remaining: 30", and the screens switches after 30 seconds. What I'm trying to figure out is how I can repaint this value every one second so that it's a live timer. The only help I've been able to find thus far is for people use components.
ActionListener listener = new ActionListener() {
int count = 0;
#Override
public void actionPerformed(ActionEvent e) {
if (count++==30) {
screenState = 0;
}
repaint();
}
};
Timer displayTimer = new Timer(1000, listener); // make it 30 times faster
You can use the a Thread that sleep it every one second using the sleep method of it
Here is a little sample that count to 30 with 1 second interval
public static void main(String[] args) {
Thread t = new Thread(new Runnable() {
#Override
public void run() {
int count = 0;
while(true)
{
if(count == 30) //end at 30 second
break;
try {
Thread.sleep(1000);
System.out.println("updated");
++count;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
t.start();
}

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