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Android: Task every 10 seconds (exactly)

We have an app who should process a task every 10 seconds. This should be more or less exact, which means that a difference of 1 or 2 seconds is OK, but not gaps of 20 seconds or more.
This should work regardless if the app is open, in foreground or in background.
We implement this via AlarmManager, but it is not working properly. If the smartphone is not plugged in and it is running in background, there are gaps in the execution.
With Android 4.3., we have gaps (about 30 seconds) from time to time, with Android 5.x we have fewer gaps, but gaps about 5 or 10 minutes long!
I think there must be a way to implement this, an alarm clock is also possible and is exact.
More about the app: It works in a service and a broadcast receiver is implemented. This means the service is restarted if I wipe away the app or restart the handy. This works correctly. The only problem is the 10 second task.
Any hints? How is an alarm clock implemented? Which calls, API?
I tried different ways until now without success.
Thanks
Hans

public void callAsynchronousTask() {
final Handler handler = new Handler();
Timer timer = new Timer();
TimerTask doAsynchronousTask = new TimerTask() {
#Override
public void run() {
handler.post(new Runnable() {
public void run() {
try {
PerformBackgroundTask performBackgroundTask = new PerformBackgroundTask();
// PerformBackgroundTask this class is the class that extends AsynchTask
performBackgroundTask.execute();
} catch (Exception e) {
// TODO Auto-generated catch block
}
}
});
}
};
timer.schedule(doAsynchronousTask, 0, 10000); //execute in every 10000 ms
}

You can do it with handler and runnable, which I think is preferred by Android..
public class ActivityMain extends Activity
{
private Handler mainHandler = new Handler();
private Runnable backgroundTask = new Runnable() {
#Override
public void run() {
//do your background task
mainHandler.postDelayed(this, 10000);
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mainHandler.postDelayed(backgroundTask, 10000);
}
}

Use of "AlarmManager" with "broadcast Receiver" and "service". These 3 component will make your requirement fulfill.
Using Alarm Manager to generate a Broadcast Receiver, and from BroadcastReceiver start a Service where you can put your desired code of logic to get your task done in every 10 Seconds.

Android Timer Schedule

Following is the code snippet which I am using in my project to schedule a task
mTimer = new Timer();
mTimer.schedule(new TimerTask() {
#Override
public void run() {
//Do Something
}
}, interval, interval);
This works fine. I get event after mentioned interval. But this fails to send any event if date is set smaller than current from settings.
Does any one know why this behavior is happening?

Timer fails when you change the system clock because it's based on System.currentTimeMillis(), which is not monotonic.
Timer is not an Android class. It's a Java class that exists in the Android API to support existing non-Android libraries. It's almost always a bad idea to use a Timer in your new Android code. Use a Handler for timed events that occur within the lifetime of your app's activities or services. Handler is based on SystemClock.uptimeMillis(), which is monotonic. Use an Alarm for timed events that should occur even if your app is not running.

Use this code.. this will help you..
Timer t;
seconds = 10;
public void startTimer() {
t = new Timer();
//Set the schedule function and rate
t.scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
if (seconds == 0) {
t.cancel();
seconds = 10;
// DO SOMETHING HERE AFTER 10 SECONDS
Toast.makeText(this,"Time up",Toast.LENGTH_SHORT).show();
}
seconds -= 1;
}
});
}
}, 0, 1000);
}

How can I control a timer in android?

I want to make an application about mini game.
Detail : In 2 seconds you must to answer a question if you don't answer or the answer is wrong -> Game Over . But if your answer is true the Timer will reset become 0 and countdown again with diffirent question.
I have already seen many code about timer in website but I don't understand clearly about it :(
So I want to ask : How can i set up a timer run only 2 seconds and how can i reset it and continue with a new question ?
Please help me.

you can use CountDownTimer in android like this:
public class Myclass {
myTimer timer =new myTimer(2000,1000);
public void creatQuestion(){
timer.start();
//method you init question and show it to user
}
public void getUserAnswer(/*evry thing you expected*/)
{
//if answer is true call timer.start()
//else call timer.onFinish(); to run onfinish in timer
}
public class myTimer extends CountDownTimer {
public myTimer(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
#Override
public void onTick(long millisUntilFinished) {
// you can update ui here
}
#Override
public void onFinish() {
this.cancel();
//fire game over event
}
}
}
i hope it make you satisfy

I've done something similar using Thread/Runnable.
Thread t = new Thread(new Runnable() {
public void run() {
final long startTime = getTime();
final long maxEndTime = startTime + 2000L;
try {
while (shouldContinueWaiting()) {
if (getTime() > maxEndTime) {
throw new TimeoutException();
}
sleep();
}
} catch (InterruptedException e) {
handleInterrupt();
} catch (TimeoutException e) {
handleTimeout();
}
}
boolean shouldContinueWaiting() {
// Has the user already answered?
}
void handleInterrupt() {
// The user has answered. Dispose of this thread.
}
void handleTimeout() {
// User didn't answer in time
}
void sleep() throws InterruptedException {
Thread.sleep(SLEEP_DURATION_IN_MILLIS);
}
void getTime() {
return System.currentTimeMillis();
}
then you can start/restart the thread by:
t = new Thread(same as above...);
t.start();
and stop by:
t.interrupt();

We want to use the Timer class.
private Timer timer;
When you're ready for the timer to start counting -- let's say it's after you press a certain button -- do this to start it:
timer = new Timer();
timer.scheduleAtFixedRate(incrementTime(), 0, 100);
The first line is us creating a new Timer. Pretty standard. The second line, however, is the one I wanted you to see.
incrementTime() is a method that is called at the end of every "tick" of the clock. This method can be called whatever you want, but it has to return an instance of TimerTask. You could even make an anonymous interface if you want, but I prefer moving it off into its own section of code.
The 0 is our starting location. We start counting from here. Simple.
The 100 is how large a "tick" of the clock is (in milliseconds). Here, it's every 100 milliseconds, or every 1/10 of a second. I used this value at the time of writing this code because I was making a stopwatch application and I wanted my clock to change every 0.1 seconds.
As for your project, I'd suggest making the timer's task be your question switch method. Make it happen every 2000 milliseconds, or 2 seconds.

You can use a Handler.
Handler h = new Handler();
h.postDelayed(new Runnable() {
#Override
public void run() {
//this will happen after 2000 ms
}
}, 2000);

Maybe this can help you:
Handler handler = new Handler();
handler.post(new Runnable() {
#Override
public void run() {
// FIRE GAME OVER
handler.postDelayed(this, 2000); // set time here to refresh textView
}
});
You can fire your game over after 2000 milliseconds.
If you get the question correct -> remove callback from handler and reset it when the next question starts.

Setting Interval For Activiry and Perform Task

Is there any function in Android that can use to make the activity wait for an interval and continue working?
I mean , for example, I use setContentView() to set a layout , and after 3 seconds it will load another layout, and continue to do another job, I don't need to repeat doing same thing after an interval, just continue do another thing.
Thanks in advanced.

You can Use Following Method to Set Interval
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
// This method will be executed once the timer is over
// Do your code here
}
}, 3000);
Here, 1000 = 1 Second
But Before running this code make sure that you are not in BACKGROUND PROCESS THREAD...otherwise this may cause an error..

Do it at Android Style:
Handler mHandler = new Handler();
mHandler.postDelayed(runnableHandler, 3000);
private Runnable runnableHandler = new Runnable() {
#Override
public void run() {
doSomething()
}
};
private void doSomething() {
// Before do something remove all callbacks from Handler
mHandler.removeCallbacks(runnableHandler);
andFinallyDoWhatYouNeed();
}

How to Delay Execution of Code For X Amount of Time in Android

On button click I want to begin a timer of 5 minutes and then execute a method that will check for certain conditions and set off alerts if conditions are right. I've seen examples with timers and postDelay, but don't really understand why one would use one vs another. What is the best way to accomplish what I am trying to do? I don't want to lock up the UI during the 5 minutes. The user should be free to use the app as normal during the countdown.
EDIT: I am trying the postDelayed suggestion but visual studio is not liking something about my code. It looks exactly like examples I've found. My be a mono for android thing.
Handler h = new Handler();
Runnable r = new Runnable(){
public void run()
{
Dialog d = inst2.showBuilder(this, "test", "test");
d.Show();
}
};
h.postDelayed(r, 5000);
Specifically the code block inside of run throws all kinds of "} expected" and "a namespace cannot directly contain members such as fields or methods" exceptions.

Try using Timer Object :
Timer mTimer = new Timer();
mTimer.schedule(new TimerTask()
{
#Override
public void run()
{
// Your code goes here
}
}, 1000); // 1sec
final Handler handler = new Handler();
Timer timer = new Timer();
timer.schedule(new TimerTask()
{
#Override
public void run()
{
handler.post(new Runnable()
{
public void run()
{
// YOUR Code
}
});
}
}, 1000); // 1sec

You can start a simple Thread that will sleep in background for 5 minutes and then call a function. While the thread sleeps in background the UI will not freeze. When the thread finish executing what you want you can set off alerts by sending some intents as notifications and receive them in some Broadcast Receivers.
Hope this helps

Use Handler.postDelayed(Runnable block); method to execute delay, as android also not recommend to use timer.

Handler h = new Handler();
Action myAction = () =>
{
// your code that you want to delay here
};
h.PostDelayed(myAction, 1000);