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CountDownTimer been decreses by 2, which should be just 1 sec

I'm creating a quiz game, and there is a countdown timer. But, the countdown decreases by two seconds, which should be just one second. My code is working okay sometimes, but when I install it again, it decreases again in 2 seconds.
countDownTimer = new CountDownTimer(timer, 1200) {
#Override
public void onTick(long l) {
timeText.setText(String.valueOf(timeValue));
timeValue = timeValue - 1;
if (timeValue == -1){
FLAG = 3;
playAudio.setAudioforEvent(FLAG);
timerDialog.timerDialog();
}
}
#Override
public void onFinish() {
// timerDialog.timerDialog();
}
}.start();

creating second counter in android eclipse

I'm making simple android app which should have counter which counts from 60 seconds down to 0 seconds. I have one idea how to do it, but I'm not sure if it is the smartest way to do it. And I'm not sure how to make it work in the code.
Idea:
In the .xml file I have added textView. I would make MyService class that extends Service which will be called by the .java file inside OnCreate function (because I want that counting starts immediately). MyService will change content of textView every second (I will have int counter which will be decreased every second and then text of textView will be changed).
Is there any better way to do it?
Here is MyService class:
public class MyService extends Service {
//for timer:
int counter = 0;
static final int UPDATE_INTERVAL = 1000;
private Timer timer = new Timer();
#Override
public IBinder onBind(Intent arg0) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
doSomethingRepeatedly();
return START_STICKY;
}
private void doSomethingRepeatedly() {
timer.scheduleAtFixedRate( new TimerTask() {
public void run() {
//code for changing the content
}
}, 0, UPDATE_INTERVAL);
}
#Override
public void onDestroy() {
super.onDestroy();
//za timer
if (timer != null){
timer.cancel();
}
}
}
Do I have to put this code in separate .java file?
I'm not sure how to write code for changing the content of textView, because I'm not sure if I can call id of textView because it is in the separated file?
These would be functions for starting the Services:
public void startService(View view) {
startService(new Intent(getBaseContext(), MyService.class));
}
public void stopService(View view) {
stopService(new Intent(getBaseContext(), MyService.class));
}
Where do I have to put them?

Use a CountDownTimer.
Schedule a countdown until a time in the future, with regular
notifications on intervals along the way. Example of showing a 30
second countdown in a text field:
new CountDownTimer(30000, 1000) {
public void onTick(long millisUntilFinished) {
mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
}
public void onFinish() {
mTextField.setText("done!");
}
}.start();
The calls to onTick(long) are synchronized to this object so that one
call to onTick(long) won't ever occur before the previous callback is
complete. This is only relevant when the implementation of
onTick(long) takes an amount of time to execute that is significant
compared to the countdown interval.

How to add time to a running countdown timer?

Before I start I have looked at lots of threads including:
How to add time to countdown timer?
Android game countdown timer
But I just cant get my timer to work in the way I require. I want the timer to be counting down from say 30 and when and image is pressed (named imageview1 in this case) the timer adds 3 seconds to the timer to give it more time. I know you cannot essentially add the time while its running and you need to cancel and then start a new timer, The code I have so far is :
public void onClick(View v) {
// TODO Auto-generated method stub
//GlobalClass global = new GlobalClass();
Random rand = new Random();
CountDownTimer thetimer = new myTimer(millisInFuture, 1000);
switch(v.getId()) {
case R.id.buttonstart:
btnstart.setVisibility(View.INVISIBLE);
thetimer.start();
break;
case R.id.imageView1:
if (thetimer != null){
thetimer.cancel();
thetimer = new myTimer(countdownPeriod + 3000, 1000).start();
}
break;
with lots of other case references then :
public class myTimer extends CountDownTimer {
public myTimer(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
#Override
public void onTick(long millisUntilFinished) {
timedisplay.setText("Time Left: " + millisUntilFinished / 1000);
countdownPeriod=millisUntilFinished;
}
#Override
public void onFinish() {
timedisplay.setText("Timer Finished");
started = false;
btnstart.setVisibility(View.VISIBLE);
}
}
I think the problem is its not cancelling the original timer so the label that shows the timer does some crazy things, like jumping around on different numbers both up and down as there would appear more than 1 class of thetimer. That is even though I have included the line thetimer.cancel(); The timer works fine if I just let it run to 0.
Any help would be great

You should not create your timer as a local in onClick. Instead create it as a global and start it somewhere else (in onCreate perhaps).
What happens with your current code is that whenever onClick is called a new timer is created and you then cancel the new timer - which has no effect on any previously created timer(s).
Try something like this:
public class MyActivity extends Activity {
CountDownTimer thetimer;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
thetimer = new myTimer(millisInFuture, 1000);
}
public void onClick(View v) {
Random rand = new Random();
switch(v.getId()) {
case R.id.buttonstart:
btnstart.setVisibility(View.INVISIBLE);
thetimer.start();
break;
case R.id.imageView1:
if (thetimer != null) {
thetimer.cancel();
thetimer = new myTimer(countdownPeriod + 3000, 1000).start();
}
break;
}
}
}
You will still have to keep track of the global time somewhere - i.e. the countDonwPeriod used to re-create the timer instance when an image is touched - it should probably be extracted from the timer before canceling it.

Java Timer equivalent in Android

I recently began working with Java and am exploring Android development. I was trying to port over one of the Java programs I made, but I am having some difficulty with getting the java Timer to function the same way in Android. I read through a number of posts and they, for the most part, indicated that it would be better to use the Handler class in android as opposed to Timer.
This was my timer in Java:
playTimer = new Timer(1000/model.getFPS(), new ActionListener() {
public void actionPerformed(ActionEvent evt) {
// do something
...
if( finished everything ) playTimer.stop();
}
});
And once a certain button was clicked, I would simply run "playTimer.start()" to start it.
As you can see, I had it set up so that the user could set the FPS they wanted (by simply setting the first parameter of the Timer class to 1000/model.getFPS()).
Now I've tried to do something similar in Android using handlers, but I am having some difficulty. It appears that the Handler ticks are not firing at the proper intervals. It seems that they are quite slow compared to what I need it to be. This is what I did in android so far:
public void startTimer() {
playHandler = new Handler();
startTime = System.currentTimeMillis();
playHandler.removeCallbacks(updateTimeTask);
playHandler.postDelayed(updateTimeTask, 0);
}
private Runnable updateTimeTask = new Runnable() {
public void run() {
// do something
...
if( finished everything ) playHander.cancel();
else {
playHandler.postDelayed(updateTimeTask, 1000/model.getFPS());
}
}
};
Excuse the semi-pseudocode. Can anyone shed any light? Thanks guys.

You can use a timer as below. The timer runs every second incrementing the counter. Displs the counter value in textview.
Timer runs on a different thread. SO you should set the text on the UI Thread.
The counter runs from 0 to 99. After 99 the timer is cancelled. Also cancel the timer when not required like in onPause().
public class MainActivity extends Activity {
TextView _tv,tv2;
Timer _t;
int _count=0;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
_tv = (TextView) findViewById( R.id.textView1 );
_t = new Timer();
_tv.setText(R.string.app_name);
_t.scheduleAtFixedRate( new TimerTask() {
#Override
public void run() {
_count++;
runOnUiThread(new Runnable() //run on ui thread
{
public void run()
{
_tv.setText(""+_count);
if(_count==99)
{
_t.cancel();
}
}
});
}
}, 1000, 1000 ); //change this value of 1000 to whatever you need.
}
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
_t.cancel();
}
}

If you decide not to use Timer (for whatever reason) you can just write a separate Thread that sleeps for x milliseconds and then wakes up and calls whatever Runnable you want it to call. That's going to be pretty precise. I have it working at the 10 millisecond level and it works quite nicely.
Just remember that it HAS to call a Runnable because a separate Thread can't have direct effect on anything on the main display thread.
public boolean keepPlayingAnimation = true
Handler h = new Handler()
Runnable updateDisplay = new Runnable(){
public void run(){
//do something in my display;
}
}
new Thread(){
public void run(){
while(keepPlayingAnimation){
try{
sleep(10);
}catch(Exception e){
}
h.post(updateDisplay);
}
}
}.start();
Just don't forget to set keepPlayingAnimation to false when you're done with this cause otherwise it will sit there running in the background for ever (or just about).

Take a look at Android Timer
It already has everything you need i guess. From ticking every 1 second to finish handly and so on.
Here is an example how to setup an TimerTask: setup
Not sure if you need such but i just remembered that i made this.

Why is my countdown timer in Android so slow?

I'm trying to make a countdown timer in android for use in a small android app. The app will countdown from some number of seconds to 0, upon which it will do some action. I'm using the coundowntimer supplied by android.os.countdowntimer. Here is my code:
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.quizlayout);
new CountDownTimer(30000, 1000) {
TextView tx = (TextView) findViewById(R.id.textView2);
public void onTick(long millisUntilFinished) {
tx.setText("seconds remaining: " + millisUntilFinished / 1000);
}
public void onFinish() {
tx.setText("done!");
}
}.start();
}
However, this countdown timer is really slow. It takes like 3 real-time seconds for the timer to countdown by one second. I wonder what's going on? The code I have above is more or less copied straight from google (CountDownTimer)
Can anyone help me as per why my timer is so slow, and offer a way to speed it up a bit?
(EDIT): I am running this on an emulator, the intel atom x86. I am emulating an android 2.3.3 environment.

According to Android documentation for countdown timer
The calls to onTick(long) are synchronized to this object so that one call to onTick(long) won't ever occur before the previous callback is complete. This is only relevant when the implementation of onTick(long) takes an amount of time to execute that is significant compared to the countdown interval.
Take a look at this example for countdown timer
Countdown timer example
Alternately you can spawn a new thread and just get that thread to sleep for the interval you want and take actions when it wakes or vice versa.
You can also timertask

use a handler that will post the same runnable . this will remove the need for extra threads :
Handler handler=new Handler();
handler.postRunnable(... , 1000) ;
in the runnable , call the postRunnable again for the same handler (and add a condition for when to stop) .

CountDownTimer is not efficient regardless to ui updating performances. For a flawless ui update, it is better to create a custom countdown. I did my own so here it is. It is flawless on my app.
public abstract class CountDown {
int totalTime = 0;
int tickTime = 0;
Thread thread;
boolean canceled = false;
public CountDown(int totalTime,int tickTime){
this.totalTime = totalTime;
this.tickTime = tickTime;
}
public abstract void onTick();
public abstract void onFinish();
public void start(){
thread = new Thread(new Runnable() {
#Override
public void run() {
// Do in thread
canceled = false;
for (int elapsedTime = 0; elapsedTime < totalTime; elapsedTime += tickTime) {
if(!canceled){
onTick();
try {
thread.sleep(tickTime);
} catch (InterruptedException e) {
e.printStackTrace();
}
}else{
break;
}
}
if(!canceled){
onFinish();
}
}
});
thread.start();
}
public void cancel(){
canceled = true;
}
}
Remember that every time you have to update your ui, call a runOnUiThread, or else you will have an exception, you are not in a handler and not on ui thread.
Here is how to use it in your code, it is identical to CountDownTimer, so you could just rename lines in your code :
CountDown cDown = new CountDown(10000, 20) {
public void onTick() {
// Do something
}
public void onFinish() {
runOnUiThread(new Runnable() {
#Override
public void run() {
myButton.setImageDrawable(drawable);
}
});
}
};