Light library to use Timer in Android. The library is implemented via Kotlin Coroutines and Kotlin Flows.

How to use

Add it in your root build.gradle at the end of repositories:

allprojects {
  repositories {
	  maven { url 'https://jitpack.io' }

Include below dependency in build.gradle of application and sync it:

implementation 'com.github.raheemadamboev:timer-flow:1.0.2'

Create an object of Timer:

val timer = Timer()

Set timer duration in milliseconds (default: 10 000):

timer.timerDuration = 5_000L

Start timer:


Observe time of timer:

lifecycleScope.launch {
    timer.time.collectLatest { time ->
      // update UI, do something

Pause timer:


If you pause timer, do not forget to stop() it. Otherwise, it runs forever.

Resume timer:


Reset timer:


Set checkpoint time (default: 3 000) that you will get notified when it is reached. It is implemented via Kotlin Channel and received as Kotlin Flow. So you will only get notified once:

timer.timerCheckpoint = 2_500L

lifecycleScope.launch {
  timer.event.collectLatest { event ->
    when(event) {
      Started -> Unit // timer started
      Checkpoint -> Unit // checkpoint reached
      Finished -> Unit // timer finished naturally, not programmatically

Observe timer states. It is implemented via Kotlin StateFlow so you always get the current timer state:

lifecycleScope.launch {
 timer.state.collectLatest { state ->
  when(state) {
   Idle -> Unit // timer is in idle position, not running
   Ticking -> Unit // timer is ticking, running
   Paused -> Unit // timer is paused, not running
   Finished -> Unit // timer is finished naturally, not programmatically finished, not running
   Stopped -> Unit // timer is stoped programmatically by calling stop() function, not running

After finished using Timer, please do not forget to stop(). Otherwise, it won’t get garbage collected!


Demo application

Very simple Jetpack Compose demo. Download demo

Italian Trulli


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