delay inside while loop not working - java

i'm trying to make a delay inside while loop using Thread.sleep() method . here is my code :
new Thread(new Runnable() {
#Override
public void run() {
z=0;
while (z<45){
z++;
handler.post(new Runnable() {
#Override
public void run() {
time.setText(Integer.toString(45-z));
}
});
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}).start();
this code was working and suddenly a problem occurred . it started to make a delay less than one minute , sumtimes 500 ms and sumtimes less than that

Instead if using a different thread, Thread.sleep(), Handler and while loop you can try only with Handler like this,
private int timerCount = 0;
private static Handler myHandler = new Handler();
private void runVVRunnable() {
myHandler.postDelayed(runnable, 1000);
}
private Runnable runnable = new Runnable() {
#Override
public void run() {
timerCount++;
if ((time == null)) {
return;
}
if (timerCount <= 45) {
time.setText(Integer.toString(timerCount));
runVVRunnable();
}
}
};
#Override
protected void onDestroy() {
super.onDestroy();
myHandler.removeCallbacks(runnable);
}
you can just call runVVRunnable() it will do the same process which you are doing while loop

Just a guess but when sleeping/waiting on Java thread you need to try-catch InterruptedException.
This exception is thrown when "someone" calls interrupt() on your thread.
This will cause the thread to wake up from sleep early than expected.
Check if you catch InterruptedException before your thread terminated.

Related

Why is not my handler executing?

I have the following code:
int x=0;
private void startTimerThread() {
System.out.println("enter");
System.out.println("percentage"+percentage);
System.out.println("x"+x);
final Handler handler = new Handler();
Runnable runnable = new Runnable() {
public void run() {
for (x = 0; x>= percentage; x++ ) {
try {
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
handler.post(new Runnable(){
public void run() {
textpercentage.animate(x, x++);
System.out.println("enter"+x);
}
});
}
}
};
new Thread(runnable).start();
}
I am trying to animate digits on a textview using timely text view, however when I call startTimerThread from my code which is outside of onCreate neither do I get the text view to display not does the system.out execute. What do I miss here?
try like this
Handler handler = new Handler();
int delay=1000;
Runnable rann=new Runnable() {
#Override
public void run() {
//Write Your logic here which you want to perform periodically
System.out.println("Handler is running : ");
//to call the same thread repeatedly calling handler again
handler.postDelayed(rann, delay);
}
};
private void startHandler() {
//here the handler will executes the rannable after that particulary delay milli seconds
handler.postDelayed(rann, delay);
}
private void stopHandler() {
handler.removeCallbacks(rann);
}

Thread imageView update speeds up

I have a thread that is used to spin an imageview as other things happen in the background. It works great for spinning, but I've noticed as I turn it on and off (based on the spinningMain variable) the button starts to spin faster and faster and faster.
I'm unsure what the cause of this is as the thread is told to sleep every 100ms.
If it helps I also have another thread (runnable thread) which runs the main code in between, which I was wondering whether it was disrupting the thread?
The imageView update thread is:
final Thread t = new Thread() {
#Override
public void run() {
try {
while (!isInterrupted()) {
Thread.sleep(100);
runOnUiThread(new Runnable() {
#Override
public void run() {
if (spinningMain == true) {
// update TextView here!
if (spinningAngleMain >= 360) {
spinningAngleMain = 0;
} else {
spinningAngleMain += 5;
}
imageButton.setRotation(spinningAngleMain);
}
}
});
}
} catch (InterruptedException e) {
}
}
};
t.start();
And the Second thread is pretty much made as follows
new Thread(new Runnable() {
#Override
public void run() {
if (searchStateButton == true) {
//do all my stuff
}
My boolean variables are set to volatile if that helps as well.

I need to stop thread when progress bar reaches 0 in android

I need stop thread and handler when my progress bar reaches 0 from 100 when thread runs the progress bar reaches but the progressStatus value going in negative please help me to stop thread after progress bar reaches 0
new Thread(runn =new Runnable() {
public void run() {
while (progressStatus <= 100) {
progressStatus += doWork();
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
// Update the progress bar
handler.post(runn1=new Runnable() {
public void run() {
bar.setProgress(progressStatus);
i=-1;
if(bar.getProgress()==0)
{
handler.removeCallbacks(runn);
handler.removeCallbacks(runn1);
System.out.println("Reached");
congrats.setVisibility(View.VISIBLE);
restart.setVisibility(View.VISIBLE);
rightbutton.setVisibility(View.GONE);
wrongbutton.setVisibility(View.GONE);
}
}
});
}
}
private int doWork() {
return i;
}
}).start();
your program is not thread safe, you actually reading and writing a variable (progressStatus) from two different threads, you must avoid doing that or if you want to do that you must use synchronized block. In order to solve your problem you can do this way:
Thread t;
progressStatus = 100;
t = new Thread(runn =new Runnable() {
public void run() {
while (!Thread.currentThread().isInterrupted()) {
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
return;
}
// Update the progress bar
handler.post(runn1=new Runnable() {
public void run() {
bar.setProgress(progressStatus);
progressStatus=progressStatus-1;
if(bar.getProgress()==0)
{
handler.removeCallbacks(runn);
handler.removeCallbacks(runn1);
System.out.println("Reached");
congrats.setVisibility(View.VISIBLE);
restart.setVisibility(View.VISIBLE);
rightbutton.setVisibility(View.GONE);
wrongbutton.setVisibility(View.GONE);
t.interrupt();
}
}
});
another way that i recommend you is using ScheduledThreadPoolExecutor with the function scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit). something like:
final ScheduledThreadPoolExecutor myTimer = new ScheduledThreadPoolExecutor(1);
myTimer.scheduleAtFixedRate(new Runnable() {
#Override
public void run() {
getActivity().runOnUiThread(new Runnable(){
#Override
public void run(){
}
});
}
}
}, 0,10, TimeUnit.MILLISECONDS);
and in order to close it use myTimer.shutdownNow();

Thread in android not working as expected

I am following a guide that shows how to create a Pong game. There is a part, where I am supposed to create a Thread, and call a function that moves the ball.
This is the code I created:
package com.ozadari.pingpong;
public class PingPongGame extends Thread {
private Ball gameBall;
private PingPongView gameView;
public PingPongGame(Ball theBall,PingPongView mainView)
{
this.gameBall = theBall;
this.gameView = mainView;
}
#Override
public void run()
{
while(true)
{
this.gameBall.moveBall();
this.gameView.postInvalidate();
try
{
PingPongGame.sleep(5);
}
catch(InterruptedException e)
{
e.printStackTrace();
}
}
}}
The thread is called and working, but it doesn't print anything. I tried to cancel the infinte loop and make the loop run 100 times. After I wait a while, it prints to the screen as it should be after 100 runs, but it doesn't print anything in the middle.
What is the problem? How can I fix it?
Unsure from the code you've posted but anyway, you can use a handler and have it run once every second like so (change the time to what you want):
Handler handler = new Handler();
final Runnable r = new Runnable()
{
public void run()
{
//do your stuff here
handler.postDelayed(this, 1000);
}
};
handler.postDelayed(r, 1000);
http://developer.android.com/reference/android/os/Handler.html
You can also use a normal thread, and call start at the end.
Thread thread = new Thread()
{
#Override
public void run() {
try {
while(true) {
sleep(1000);
handler.post(r);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
thread.start();

I can't finish thread (runnable), how it is?

Thread thread;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_yippi);
final Handler hn=new Handler();
final TextView text=(TextView)findViewById(R.id.TextView01);
final Runnable r = new Runnable()
{
public void run()
{
text.settext("hi");
}
};
thread = new Thread()
{
#Override
public void run() {
try {
while(true) {
sleep(1750);
hn.post(r);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
}
};
thread.start();
thread.stop();}
The code here. I can not stop the runnable thread. Also, thread.stop() and thread.destroy() are deprecated. Can somebody help me? And also I don't understand how to stop the thread with the thread.interrupt() method. What's wrong?
The JavaDoc for Thread.stop() lists the following article as explanation for why stop() is deprecated: http://docs.oracle.com/javase/6/docs/technotes/guides/concurrency/threadPrimitiveDeprecation.html
Most uses of stop should be replaced by code that simply modifies some variable to indicate that the target thread should stop running. The target thread should check this variable regularly, and return from its run method in an orderly fashion if the variable indicates that it is to stop running. To ensure prompt communication of the stop-request, the variable must be volatile (or access to the variable must be synchronized).
interrupt() is more suitable to stop some Thread from waiting for something, that is probably not coming anymore. If you want to end the thread, it's best to let its run() method return.
Create a boolean variable to stop the thread and use it in while(boolean) instead of while(true).
You can use Thread.interrupt() to trigger the InterruptedException within your thread. I've added code below that demonstrates the behavior. The mainThread is where your code would be and the timer Thread is just used to demonstrate delayed triggering of the interrupt.
public class Test {
public static void main(String[] args) {
final Thread mainThread = new Thread() {
#Override
public void run() {
boolean continueExecution = true;
while (continueExecution) {
try {
sleep(100);
System.out.println("Executing");
} catch (InterruptedException e) {
continueExecution = false;
}
}
}
};
mainThread.start();
Thread timer = new Thread() {
#Override
public void run() {
try {
sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Stopping recurring execution");
mainThread.interrupt();
}
};
timer.start();
}
}
You can use interrupt method of Thread to try stop a thread, like below code.
May be it`s useful to you.
public class InterruptThread {
public static void main(String args[]){
Thread thread = new Thread()
{
#Override
public void run() {
try {
while(true) {
System.out.println("Thread is Runing......");
sleep(1000);
}
} catch (InterruptedException e) {
// restore interrupted status
System.out.println("Thread is interrupting");
Thread.currentThread().interrupt();
}
}
};
thread.start();
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Will Interrupt thread");
thread.interrupt();
}
}

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