I am using BroadcastChannel as Flow But it is not ...

# coroutines

[Rohan Maity]

I am using BroadcastChannel as Flow
But it is not receiving anything in collect

tunnel.pipe.send("LOPI")

            tunnel.pipe.asFlow().flowOn(Dispatchers.Main).collect {

                tvPUI.text = it.toString()
            }

            delay(2000)

            tunnel.pipe.send("HOLA")

[tseisel]

collect suspends until the source channel is closed, therefore "HOLA" could not be sent

[Rohan Maity]

Ok so If I wanna use it as Hot observable do I have to some other way ?

[Rohan Maity]

AFAIU BroadcastChannel could be used as PublishSubject

[wasyl]

You can use it like this, just launch the collection in a separate coroutine (launch { ..collect { } })

[Rohan Maity]

yes It is working 🙂

[Rohan Maity]

But quite still ambiguous why ?

[Rohan Maity]

Is it because when I did the first send and since its suspend function that whole coroutine was suspended (including collection)

[Rohan Maity]

and it was awaiting for collection

[Rohan Maity]

but then there was no collection since it was kinda suspended forever ?

[wasyl]

When you launch a single coroutine, it runs whatever is inside sequentially. collect { } starts collecting the flow and only completes (returns) when the flow finishes (channel closes). But the new coroutine started with launch runs concurrently, so launch { } call returns immediately, allowing your send to be actually called

[wasyl]

But, with the other launch do you receive tunnel.pipe.send("LOPI")? Because I’m not sure you should, as you send it before flow is collected, and channels are hot, which means LOPI should be lost

[Rohan Maity]

no, I did not. and that is what I was expecting it

[Rohan Maity]

thanks @wasyl 😄

[darkmoon_uk]

Just to clarify - even putting the underlying implementations aside - your example shows a conceptual gap: "LOPI" should be 'lost' as a Flow is hot and there's no receiver at that point.

[Rohan Maity]

flow is cold as far as I have read in medium articles Its channel what are hot
I intended that "LOPI" should be lost as well

[Rohan Maity]

So when I used send "LOPI" (which is suspend) and since I also tried collection in same coroutine. and there was no receiver for "LOPI" that whole coroutine was suspended
therefore collection was never completed in first place