Instead of LiveData, I'm using StateFlow in my Vie...

# flow

[dephinera]

Instead of LiveData, I'm using StateFlow in my ViewModel to emit values to the UI. I realized that StateFlow doesn't emit equal values. How do you approach that? What if you want to emit multiple times the same value to show some message pop-up/toast/smth?

[bezrukov]

you can use SharedFlow, it doesn't conflate equal values

[bezrukov]

one more drawback of using StateFlow for your use case is that StateFlow is also drops emission if collector wasn't able to consume it before new one arrives.
For example:

state.value = Toast("Text A")
state.value = Toast("Text B")
state.value = Toast("Text C")

Collector [most likely, it depends on collector's Dispatcher] will receive only "Text C"

It also can be fixed with shared flow by introducing extra buffer

[dephinera]

Thanks!

[Javier]

if the state is not changing, what is the reason to redraw the scren?

[dephinera]

As I mentioned, this might be a popup. For example a toast message that displays "success" every time an operation success

[Javier]

then you have to wonder if you are going to manage them as state or as event

[dephinera]

You're right that it's more like an event. What would be the proper approach in that case? Is MutableSharedFlow still the way to go

[Javier]

and probably you should use channels instead of shared flow if you go for events

[dephinera]

I see

[Javier]

https://elizarov.medium.com/shared-flows-broadcast-channels-899b675e805c

[Javier]

Channels are used to handle events that must be processed exactly once* (see sidenote below for details).

[Javier]

another option is reset de state

[Javier]

but not sure if toast allow to know when they are disappearing

[dephinera]

After reading the article, MutbaleSharedFlow still sounds as the best fit for the scenario

[Kamil Kalisz]

You can always wrap your event in some generic Event class. ( Or expand your base class) that will contain for example creation timestamp. So each event even with the same message will be different in terms of equality

[dephinera]

This sounds more like a "fighting the framework" solution