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Getting elapsed time from AlarmManager

Pretty new to android, so forgive me if this is a dumb question...
So, I'm making an app with a countdown timer that will ring periodically, and then again when the countdown hits zero - simple enough. However, I want the app to keep running even when the user closes the application or the phone is asleep, so that whenever the timer rings, the app will wake up and display an activity showing the time until the countdown is finished. To do this, I'll need to use a service, and lo and behold, the google devs made the AlarmManager service just for me! Sweet!
However, I noticed 2 things:
1) the AlarmManager class has no default constructor, so I'm assuming I can't just extend it and tack some logic on so that I can get all this done in one shot. Ok, cool - I'll just make a service that instantiates AlarmManager at the start, and implement my logic there.
2) In the documentation, I don't see any way of getting either the elapsed time or the remaining time from AlarmManager once it is running.
So, my question is: does this mean that I will need two timers that I start at the same time? Say, an AlarmManager to wake the phone up and call the activity, and a CountDownTimer contained in the service to hold the remaining time and call the alarm ringtone?
Thanks for helping out my clueless ass.

You could extend AlarmManager. However the common way is to get an instance of it, which is running as a system service.
Get the instance using Context.getSystemService(Context.ALARM_SERVICE) and you will be able to register your PendingIntent to that system service, which is independent to your own app. The PendingIntent can either start an activity or send broadcast with some Intent. You don't monitor the elapsed time constantly in AlarmManager. Rather, you calculate the time difference between the current time of your method call, and the desired time to fire your event. And then you set an alarm in AlarmManager with a PendingIntent representing the action you wish to take at that interval, or a time point.
On the other hand, if you want maximum flexibility, run your service as foreground service and listen for system broadcast like ACTION_TIME_TICK, which is fired every minute. Alternatively if you don't run service in foreground you could also run your service with START_STICKY, which guarantees that your service will be restarted after the system kills it (due to sleep or closing app). Think this as a background service that is constantly running. This provides you a lot of flexibility in your implementation.

Count-down timer/alarm API for android

I'm learning Android and want to write some kind of count-down timer application, so I get a ring-tone after certain minutes are elapsed. The timer also should work if the user has closed the application or switched to another one. If my application is running, it should be able to display the remaining time.
I've tried with CountDownTimer, but this seems only to work when the phone is activated, but not like the alarms which could ring you up at the morning. What other similar API alternatives are there to activate the device if the time is elapsed?

You can use AlarmManager for this purpose.

count-down and alarm are two very different things (even thou both count time).
Count-down you probably want to run a service and put a notification with the flag ongoing = true updating the value of the time.
Alarm you want to use the AlarmManager (as pointed out by #PgmFreek) that you can schedule a specific time that the system will call an Intent for you.

Need to implement a timeout feature when application goes to background

I need to create a timeout feature when my app goes to the background for 5 minutes(anything that fires up onPause() except when activity is finishing). If the user goes back to the application then the timer should be cancelled.
Also, I need the timer to be not dependent on the time set in the phone meaning when the app goes to the background and then the user changes the time the application will still timeout within 5 minutes.
Checking out the documentation of the AlarmManager it states the following:
Note: The Alarm Manager is intended for cases where you want to have your application code
run at a specific time, even if your application is not currently running. For normal
timing operations (ticks, timeouts, etc) it is easier and much more efficient to use
Handler.

Alternatively, you could try setting up bound service - these can operate in background even if user toggles frontmost application. you can communicate with the service using Handler, just as you would do with threads.
the easiest would be to use sendEmptyMessageDelayed of predefined type and use call to removeMessages() once your app is back on top.

You should take a look at the AlarmManager. You can easily program your app to run at a specific time or every 5 minutes with a PendingIntent. You can cancel it with the same PendingIntent.
I don't know about the time dependency but it's easy to test.

in onPause() set an alarm using AlarmManager, like this:
AlarmManager alarmManager = getSystemService(Context.ALARM_SERVICE);
// Alarm time is elapsed time since boot (including sleep) plus 5 minutes
long alarmTime = SystemClock.elapsedRealtime() + 5 * 60 * 1000;
alarmManager.set(AlarmManager.ELAPSED_REALTIME, alarmTime, pendingIntent);
For the pendingIntent() you can use either a broadcast Intent or you can have it start one of your activities. Depends what you want to do when the alarm goes off.
NOTE: Using AlarmManager.ELAPSED_REALTIME ensures that changes the user makes to his date/time settings won't have any effect on your 5 minute timeout.
Make sure to cancel the alarm when your app resumes (in onResume()) and when it finishes (in onDestroy())

I wonder if the easiest solution wouldn't be to just set a value in sharedPreferences when your activity pauses and test this value again onResume. To avoid the value being corrupted by the user changing the clock you could employ SystemClock.elapsedRealtime() or SystemClock.uptimeMillis()

Android: Stopping Alarm at specific time and service clarification

is there any way to stop an alarm at a given time, for example, i started an alarm on 7:45am and it repeats every 5 minutes and then, i wanted to stop that alarm when the time is already 8:00am?
How do i go about this algorithm since alarm manager's cancel() method only accepts an action (PendingIntent)
and Secondly, regarding services, i have an idea to put a checker or an if statement on service to check if its already 8:00a, but im not sure if service always run in the background and if so, does that mean to say that it always checks the time if its 8am? given that meaning of services that once it started i won't stop unless explicitly told to do so.
any of you guys know any way to do this please do share, im kinda confused right now

you will have to start the service when alarm start first time and this service will ring the alarm at 5 min and get the device time and compare it with the time to stop the time
at that (means at 8 AM )stop your service

Why dont you start whatever you need to do at 7:45am with AlarmManager#setRepeating and set another alarm with AlarmManager#set to stop the previous?
AlarmManager#set will be fired off just once, so you can use it cancel the repeating alarm
Edit:
In the implementation of AlarmManager#set, you would retrieve the repeating alarm(AlarmManager#setRepeating) and cancel() it

Android, Is it poosible to use system timer as broadcast receiver?

In my application I need to refresh my data in each 5s or 10s or 1 minute, according to my user preference.
I can create thread and use timer class but i want to know is there any other way? for example timer of system sends flag (broadcast something) and i get it in application (in order to refresh my data)?
Thanks

If you want to refresh the data every serval seconds, you can setup a Hanlder to do this. However, this requires your activity keeps running.
If you want to do something at a specific time, like an Alarm. You can use the AlarmManager. This would lauch your activity or other components even it is not running now.
If you just want to moniter the change in the system time. Well, there is a Intent ACTION_TIME_TICK . You can register a BroadcastReceiver to listent to it and implement your own code when the systemt brocasts it. However, the "TICK" interval is "One Minute" only and can not be changed.

AlarmManager is what you are looking for. It can be used to set up periodic events that are delivered via a PendingIntent (which can be turned into an Intent broadcast).
I would be wary checking for new data on such a regular interval unless the device is always connected to a power source, especially if you are making the check over a network. With that small a poll interval going to the nework the battery will be flat in hours.