I'm developing a game where LittleMan can move from block to block, and certain blocks are moving. I'm trying to detect when he moves to a new moving block, if that block is beneath him or if it has moved. I'm using Andengine's TimerHandler to check every 0.1 seconds but it is not working. Here's the code:
private void OnMovingBlock(final int CurrentPosRow, final int CurrentPosColumn) {
this.getEngine().registerUpdateHandler(new TimerHandler(0.1f, true, new ITimerCallback() {
#Override
public void onTimePassed(final TimerHandler pTimerHandler) {
if (LittleManPos[0] == CurrentPosRow && LittleManPos[1] == CurrentPosColumn) {
if (!LittleMan.collidesWith(MapRectangles[CurrentPosRow][CurrentPosColumn])) {
RestartScene();
}
}
}
}));
}
It seems he can move to the block and sit there with it moving in and out beneath him but it doesn't call RestartScene() UNTIL I move him again. Any idea where I am going wrong? Or is there another way to do this?
Why don't create a Timer?
TimerTask task = new TimerTask(){
#Override
public void run(){
// your code goes here
}
};
Timer timer = new Timer();
timer.sechedule(task, 0, 100); // 100 --> 0.1 second
To cancel the Timer, call timer.cancel();.
Related
I am still a very early coder and still don't know everything about java so my code is still a bit messy, sorry about that. I am making a simple platformer game with the graphics g class and I'm trying to figure out how to delay a method without pausing the entire script.
I have tried Thread.sleep() and TimeUnit.SECONDS.sleep() but both of these freeze other methods running at the time, and the Timer that keeps the game running.
private static Timer timer;
private int delay = 10;
public Gameplay() {
addKeyListener(this);
setFocusable(true);
setFocusTraversalKeysEnabled(false);
timer = new Timer(delay, this);
timer.start();
}
public void moveDown() {
if (play == true) {
Playsound("drop");
dropping = true;
//pause here for 1 second without freezing timer or other running methods
dropping = false;
}
}
I want the program to continue running while waiting, but the things I have tried always freeze the entire program
One trick from my side
public void moveDown() {
if (play == true) {
Playsound("drop");
dropping = true;
//create a thread which will execute your method and set sleep on that thread
dropping = false;
}
try this
...
Thread thread = new Thread(() -> moveDown());
thread.run();
...
void moveDown() {
//do some work
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
//continue your work
}
explanation
you need to stop thread , but you dont want to stop current thread :)
that means you need to run your work on background thred and stop only it,
this is not best solution , its just for explanation how you can do it.
Lets say I have a ImageView that executes at a click of a Button:
final ImageView ball = new ImageView(v.getContext());
ball.setImageResource(R.drawable.ball_1);
gameConstraintLayout.addView(ball);
When I click that button, it first off makes the ball appears , creates and runs another thread that tell itself to sleep 1000 milliseconds sleep(long millis) then removes the ball by calling ConstrainLayout.removeView(view)
Here is the full minimal code:
final ImageView ball = new ImageView(v.getContext());
currentBullet.setImageResource(R.drawable.ball_1);
gameConstraintLayout.addView(ball);
ballAppears.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(final View v) {
final ImageView ball = new ImageView(v.getContext());
currentBullet.setImageResource(R.drawable.ball_1);
gameConstraintLayout.addView(ball);
Thread thread = new Thread() {
#Override
public void run() {
try {
sleep(1000);
contraintLayout.removeView(ball)
} catch (InterruptedException e) {
e.printStackTrace();
}
});
}
});
Problem is;
The ball appears on screen, the other thread successfully sleeps for 1000 milliseconds, but, It crashes when It tries to remove the ball from the constraint layout in the other thread.
Logcat:
android.view.ViewRootImpl$CalledFromWrongThreadException: **Only the original thread that created a view hierarchy can touch its views**.
at android.support.constraint.ConstraintLayout.removeView(ConstraintLayout.java:645)
at com.mobilegames.***.******.GameActivity$1$1.run(GameActivity.java:51)
The code that causes the problem is:
gameConstraintLayout.removeView(ball_1);
AS it seems,I cant access the Constraint layout from the other thread but, I can still change the X and the Y of the ball.
I even tried running that piece of code in the UI theard runOnUIThread(...), but to no avail.
Here is the runONUIThread code:
shootTank.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(final View v) {
final ImageView currentBullet = new ImageView(v.getContext());
currentBullet.setImageResource(R.drawable.bullet_model1);
gameConstraintLayout.addView(currentBullet);
Thread thread = new Thread() {
#Override
public void run() {
try {
sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
runOnUiThread(new Runnable() {
public void run() {
gameConstraintLayout.removeView(currentBullet);
}
});
}
};
thread.start();
}
});
Any possible solutions? Keep in mind that I change the X and Y's of the ball after every second.
AND YES, I did check other Questions. The answer in those ones said to simply run it on the UI thread, but of course I already tried that. If i run the sleep(long millis) into the UI thread, obliviously, the whole app would be irresponsible.
(This is not the full app; it was broken down into a much more simpler and understandable Question. I end up changing the ball's X and Y in the separate thread, but that inst what is causing the problem. Please tell me in comments if editing is necessary)
Sorry for small grammar mistakes
Use handler to perform your actions with some delay. For example:
Handler h = new Handler();
h.postDelayed(new Runnable() {
public void run() {
gameConstraintLayout.removeView(currentBullet);
}
}, 1000); // here 1000 is delay in milliseconds (1sec)
I need to make a GUI where a worker enters a station (a spot on the panel) and stays there for a set amount of seconds, shown in a countdown about the workers head (so, once the workers moves to the spot, the station's label shows 3s -> 2s -> 1s and then the worker leaves, and the label reverts back to "OPEN"). I'm having trouble with making this happen, as I'm not too good with the Timer(s?) that Java has. I tried with something like this:
Timer timer = new Timer(1000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e)
{
//change label text/color, decrement countdown
panel.repaint();
Thread.sleep(1000);
}
});
But I can't reach the number of seconds to count down from from inside the timer, and I'm not sure how to pass that value to the timer. If someone can help me out, I'd really appreciate it.
Get rid of the Thread.sleep(). That's what the 1000 in Timer(1000, new ActionListener() does. It sets an interval for each timer event. Every time a timer event is fired, the actionPerformed is called. So you need to determine what needs to happen every "tick", and put that code in the actionPerformed. Maybe something like
Timer timer = new Timer(1000, new ActionListener() {
private int count = 5;
#Override
public void actionPerformed(ActionEvent e) {
if (count <= 0) {
label.setText("OPEN");
((Timer)e.getSource()).stop();
count = 5;
} else {
label.setText(Integer.toString(count);
count--;
}
}
});
You need to decide when to call timer.start().
For general information, see How to Use Swing Timers
Problem #1: You are calling Thread.sleep() from within the Swing GUI thread. That causes the thread to stop taking input and freeze. Delete that line. It does you no good! While you are at it, delete the repaint call as well.
Now that that's said and done, instead of creating an anonymous instance of ActionListener, you can create an actual class that implements ActionListener and provides a constructor. That constructor can have as an argument the number of seconds you want to start counting down. You can declare that class inside the method you are using, or you can declare it inside the class.
Here's a skeletal example:
public class OuterClass {
JLabel secondsLabel = ...;
Timer myTimer;
private void setupTimer(int numSecondsToCountDown) {
secondsLabel.setText(Integer.toString(numSecondsToCountDown));
myTimer = new Timer(1000, new CountdownListener(numSecondsToCountDown));
myTimer.start();
}
// ...
class CountdownListener implements ActionListener {
private int secondsCount;
public CountdownListener(int startingSeconds) { secondsCount = startingSeconds; }
public void actionPerformed(ActionEvent evt) {
secondsLabel.setText(Integer.toString(secondsCount);
secondsCount--;
if (secondsCount <= 0) { // stop the countdown
myTimer.stop();
}
}
}
}
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?
I am trying to use a time that updates a label every second (so it shows a countdown) but it only
appears to be "ticking" once and I can't work out what I'm doing wrong!
public class Puzzle extends UiApplication {
public static void main(String[] args) {
Puzzle puzzle = new Puzzle();
puzzle.enterEventDispatcher();
}
public Puzzle() {
pushScreen(new PuzzleScreen());
}
}
class PuzzleScreen extends MainScreen {
LabelField timerLabel;
Timer timer;
public static int COUNT = 0;
public PuzzleScreen() {
//set up puzzle
VerticalFieldManager vfm = new VerticalFieldManager();
add(vfm);
timerLabel = new LabelField();
timerLabel.setText("00:20");
vfm.add(timerLabel);
StartTimer();
}
void StartTimer() {
timer = new Timer();
timer.schedule(new TimerTick(), 1000);
}
private class TimerTick extends TimerTask {
public void run() {
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
timerLabel.setText((COUNT++) + "");
}
});
}
}
Can anyone see what I am doing wrong..? All that happens is my label get's set to "0" and then doesn't change. I have put a breakpoint on the run in the timer tick class but I don't see it firing!
Bex
You'll need to change your Timer's schedule() call to
timer.schedule(new TimerTick(), 0, 1000);
The way you're calling it right now is saying to run it once after a second delay. This way says to run it now and every second. You probably want to use
timer.scheduleAtFixedRate(new TimerTick(), 0, 1000);
though, because it will make sure that on average your TimerTask is ran every second rather than with a normal schedule() call that says it will try waiting a second then executing, but it could fall behind if something slows it down. If scheduleAtFixedRate() is delayed, it will make multiple calls quicker than on the 1 second delay so it can "catch up." Take a look at http://www.blackberry.com/developers/docs/5.0.0api/java/util/Timer.html#scheduleAtFixedRate(java.util.TimerTask,%20long,%20long) for a more detailed explanation.