Emit value if specific time has passed after last item

Question

I've got an observable: Observable.create<Boolean> {emitter = it}, to which I push some values. I want it to publish a 'false' value, as soon as some specific time period has passed without any value being pushed to that emitter.

How is that possible with RxJava/Kotlin 2?

Answer 1

You can try to combine 2 functions: timeout and onErrorReturn.

Observable.create<Boolean> { 
    // use emitter here
}
     .timeout(3, TimeUnit.SECONDS)
     .onErrorReturn { if (it is TimeoutException) false else throw it } 
     .subscribe { println("onNext $it") }

Updated snippet after clarification. repeatWhen will resubscribe to Observable.

Observable.create<Boolean> { 
    // use emitter here
}
    .timeout(3, TimeUnit.SECONDS)
    .onErrorReturn { if (it is TimeoutException) false else throw it }
    .repeatWhen { it }
    .subscribe { println("onNext $it") }