Observable's events not received

Asked Sep 01 '16 at 14:56

Active Sep 01 '16 at 14:56

Viewed 39 times

I have a variable called responses of type Observable[Try[Int]] that emits either:

Success(n), where n is a natural number or Failure(Exception)

I am summing the values of this observable like this:

val sum = responses.foldLeft(0) { (acc, tn) =>
  println("t1 tn: " + tn)
  println("t1 acc: " + acc)
  tn match {
    case Success(n) => acc + n
    case Failure(t) => acc // Failures are 0
  }
}

The print statements show this:

t1 tn: Success(1)
t1 acc: 0
t1 tn: Success(1)
t1 acc: 1
t1 tn: Success(1)
t1 acc: 2
t1 tn: Success(2)
t1 acc: 3
t1 tn: Failure(java.lang.Exception)
t1 acc: 5
t1 tn: Success(3)
t1 acc: 5
t1 tn: Success(3)
t1 acc: 8
t1 tn: Success(3)
t1 acc: 11

Immediately after, I am trying to get the sum from the observable like this:

var total = -1
val sub = sum.subscribe {
  s => {
    println("t1 s: " + s)
    total = s
  }
}

However, here, total is never updated and the print statement never shows anything.

Why is this the case?

Why are events not passed along any more?

asked Sep 01 '16 at 14:56

bsky

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Your sum seems to be an Int type after the fold operation. How are you running a subscribe on an int value? – Samar Sep 01 '16 at 15:24
It's `Observable[Int]`, not `Int` – bsky Sep 01 '16 at 15:28
The result of a fold operation is of the same type as the starting value of the acc which is 0 in your case. So the fold operation should return an Int. I might be missing something here??? – Samar Sep 01 '16 at 15:43
Your code works fine for me, prints t1 s: xx – Nyavro Sep 01 '16 at 16:23
Is it asynchronous? If so, then it may be because the main thread exits. – zsxwing Sep 13 '16 at 22:21

Observable's events not received

0 Answers0