RxJava2：不是的onComplete與所謂flatMapIterable

Question

這裏是代碼一小段：

val subject = BehaviorSubject.createDefault(emptyList<Int>()) 
    subject.onNext(Arrays.asList(1, 2, 3)) 
    subject.flatMapIterable { list: List<Int> -> list } 
      .subscribeBy(
        onNext = { l("on next", it) }, 
        onComplete = { l("on complete") } 
      ) 

爲什麼onComplete沒有不叫嗎？我應該怎麼做這個代碼？因爲在原始代碼中我不能使用.toList()方法。

Answer 1

BehaviorSubject你的形式是一個無限的來源，除非onComplete被稱爲它。因此flatMapIterable將不會完成，並且您的onComplete處理程序將永遠不會被調用。

因此，無論你完成BehaviorSubject：

val subject = BehaviorSubject.createDefault(emptyList<Int>()) 
subject.onNext(Arrays.asList(1, 2, 3)) 
subject.flatMapIterable { list: List<Int> -> list } 
     .subscribeBy(
       onNext = { l("on next", it) }, 
       onComplete = { l("on complete") } 
     ) 

subject.onComplete() // <----------------------------------------------------- 

，或者你

val subject = BehaviorSubject.createDefault(emptyList<Int>()) 
subject.onNext(Arrays.asList(1, 2, 3)) 
subject.take(1) // <---------------------------------------------------------- 
     .flatMapIterable { list: List<Int> -> list } 
     .subscribeBy(
       onNext = { l("on next", it) }, 
       onComplete = { l("on complete") } 
     )