我们如何在每毫秒内缓冲项目并以固定的时间间隔流式传输每个项目

时间:2019-01-11 14:08:06

标签: android kotlin rx-java rx-java2 rx-kotlin2

publishSubject的onNext方法正在连续调用(在不均匀的时间中,大约在1毫秒内) 并且要求每1秒钟发出一次这些项目,并且数据不应该丢失意味着应该发射每个项目。

    publishSubject.onNext("Data1");
    publishSubject.onNext("Data2");
    publishSubject.onNext("Data3");
    publishSubject.onNext("Data4");
    publishSubject.onNext("Data5");
    publishSubject.onNext("Data6");
    publishSubject.onNext("Data7");

,依此类推... 请参阅代码结构以供参考:

var publishSubject = PublishSubject.create<String>()
publishSubject.onNext(stateObject) // Executing at every milliseconds...


publishSubject
        /* Business Logic Required Here ?? */
        .subscribeOn(Schedulers.computation())
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe {
            // Should execute at every 1 second
        }

请帮助,在此先感谢

2 个答案:

答案 0 :(得分:1)

如何将物品存储在双端队列中。然后,使用协程启动挂起功能来每秒获取双端队列的第一个元素?

这里有一些又脏又的代码只是为了确保它能正常工作。 您可以在kotlin website上在线运行此代码。 请记住,我是Kotlin的新手。

val deque: Deque<String> = ArrayDeque()
var refMillisAdd: Long = 0
var refMillisTake: Long = 0

fun main() {

    println(" Delay(ms) -> Action")
    println("---------------------")

    kotlinx.coroutines.runBlocking {

        launch {

            refMillisAdd = currentTimeMillis()
            refMillisTake = currentTimeMillis()

            for(i in 0..20){
               oncePer10ms(i.toString())
               refMillisAdd = currentTimeMillis()
            }

            for(i in 0..6){
                oncePerSecond()
                refMillisTake = currentTimeMillis()
            }
        }
    }
}

suspend fun oncePerSecond(){
    kotlinx.coroutines.delay(1_000L)
    println("  ${currentTimeMillis() - refMillisTake} -> TAKE ${deque.pop()}")
}

suspend fun oncePer10ms(item: String){
    kotlinx.coroutines.delay(10L)
    deque.add(item)
    println("  ${currentTimeMillis() - refMillisAdd} -> ADD $item")
}

上面的代码打印:

 Delay(ms) -> Action
---------------------
  17 -> ADD 0
  11 -> ADD 1
  10 -> ADD 2
  10 -> ADD 3
  10 -> ADD 4
  10 -> ADD 5
  10 -> ADD 6
  10 -> ADD 7
  10 -> ADD 8
  11 -> ADD 9
  10 -> ADD 10
  10 -> ADD 11
  10 -> ADD 12
  11 -> ADD 13
  10 -> ADD 14
  10 -> ADD 15
  11 -> ADD 16
  10 -> ADD 17
  10 -> ADD 18
  10 -> ADD 19
  11 -> ADD 20
  1223 -> TAKE 0
  1000 -> TAKE 1
  1000 -> TAKE 2
  1001 -> TAKE 3
  1000 -> TAKE 4
  1000 -> TAKE 5
  1000 -> TAKE 6

答案 1 :(得分:1)

Observable类的功能扩展正是您需要的:

fun <T> Observable<T>.delayBetweenItems(timeout: Long, unit: TimeUnit): Observable<T> =
    Observable.zip(this, Observable.interval(timeout, unit), BiFunction<T, Long, T> { item, _ -> item })

您可以在项目的某些实用工具类中对其进行声明,然后像其他 RxJava 运算符一样应用它:

publishSubject
    .delayBetweenItems(1000, TimeUnit.MILLISECONDS)
    .subscribeOn(Schedulers.computation())
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe {
        // Should execute at every 1 second
    }