How to call a function after delay in Kotlin?

You could launch a coroutine, delay it and then call the function:

 /*GlobalScope.*/launch {
   delay(1000)
   yourFn()
 }

If you are outside of a class or object prepend GlobalScope to let the coroutine run there, otherwise it is recommended to implement the CoroutineScope in the surrounding class, which allows to cancel all coroutines associated to that scope if necessary.


You can use Schedule

inline fun Timer.schedule(
    delay: Long, 
    crossinline action: TimerTask.() -> Unit
): TimerTask (source)

example (thanks @Nguyen Minh Binh - found it here: http://jamie.mccrindle.org/2013/02/exploring-kotlin-standard-library-part-3.html)

import java.util.Timer
import kotlin.concurrent.schedule

Timer("SettingUp", false).schedule(500) { 
   doSomething()
}

Many Ways

1. Using Handler class

Handler().postDelayed({
    TODO("Do something")
    }, 2000)

2. Using Timer class

Timer().schedule(object : TimerTask() {
    override fun run() {
        TODO("Do something")
    }
}, 2000)

// Shorter

Timer().schedule(timerTask {
    TODO("Do something")
}, 2000)


// Shortest

Timer().schedule(2000) {
    TODO("Do something")
}

3. Using Executors class

Executors.newSingleThreadScheduledExecutor().schedule({
    TODO("Do something")
}, 2, TimeUnit.SECONDS)

There is also an option to use Handler -> postDelayed

 Handler().postDelayed({
                    //doSomethingHere()
                }, 1000)

Tags:

Android

Kotlin