Hi all, I'm currently trying to replace usages of

Channel

with

Flow

in my Android application. But now I'm stuck in a conceptual thinking problem: Right now I use

Channel

to handle UI events on Android views, for instance clicks inside a

RecyclerView.Adapter

. I create an instance of

Channel

in the view (or presenter, it doesn't matter) and pass it to the

RecyclerView.Adapter

. Then inside the adapter I could just pass click events to the channel. But with

Flow

, the flow needs to be created at the place where the data is emitted. However I don't want to have x flows in my Adapter for every view the adapter manages. Is

Flow

even suited for UI events or are UI events classically hot streams? Am I just trying to apply

Flow

where

Channel

is the right choice after all?

Yeah, those UI events are hot since you want the click event itself and the handler to be fully decoupled but listening.

Thanks Bradyn, that's what I tought

Flow

isn't necessarily a replacement for

Channel

-

Channel

is appropriate for 'hot' events like live interactions with your UI.

Thanks Chris, I'm already using

ConflatedBroadcastChannel

🙂 So basically channels are the right choice for hot UI events

Yep

But I might replace

Channel

with

Flow

for my API requests

Yep, or note you can use

asFlow

to gain the Flow-API benefits for any

BroadcastChannel

.

Let’s bikeshed a name: https://github.com/Kotlin/kotlinx.coroutines/issues/1082#issuecomment-525650399

@elizarov

StateFlow

is most incisive, because: - Data Flow implies data in an untyped, raw form, which this is (usually) not. - Value Flow somewhat clashes by name with Kotlins

val

, implying unchanging, or constant, which this is not. - State Flow - as you said yourself, succinctly point to the fact there is an ever-present state of this thing, which can be accessed... but which flows, changes.

One more question: Trying to replace

Channel

with

Flow

for my API requests. Using Firebase Firestore here and want to listen for document updates. As of now I create a

Channel

, then on the Firestore

Query

I call `addSnapshotListener()`and inside the listener I call

channel.offer()

when there are snapshots incoming. Also I call

channel.invokeOnClose { registration.remove() }

where

registration

is the

ListenerRegistration

returned by

addSnapshotListener

. How do I perform the last step with

Flow

, ensuring that no listeners are leaked?

Use

callbackFlow

.