This is something I came up ``` private val state = liveData kotlinlang #coroutines

private val _state = liveData<LoginViewState> {
        coroutineScope {
            launch {
                usernamePasswordChannel.consumeEach { (username, password) ->
                    validateLoginDataUseCase.validateLoginData(
                        username,
                        password
                    ).perform(latestValue!!).also { emit(it) }
                }
            }
            launch {
                isLoggingInChannel.consumeEach {
                    usernamePasswordChannel.value.let { (username, password) ->
                        performLoginUseCase.login(
                            username,
                            password
                        )
                    }.perform(latestValue!!).also { emit(it) }
                }
            }
        }
    }

It looks a bit odd, has anyone any suggestion about something I’m misusing or that can be optimised in terms of code?

marstran

10/18/2019, 10:39 AM

I think you can use

select

to read from both channels without having consume them in two launch-tasks.

Dominaezzz

10/18/2019, 10:48 AM

You can use

asFlow

on the

BroadcastChannel

and

consumeAsFlow

on the

Channel

. Then use flow operators to combine them.

alexfacciorusso

10/18/2019, 10:54 AM

and then consume the final flows in the live data block itself?

also, how would you transform a Flow in a way the logic would make sense in the same way as the one I wrote with coroutines?

Dominaezzz

10/18/2019, 11:09 AM

Like,

usernamePasswordChannel.asFlow().map { (username, password) ->
   validateLoginDataUseCase.validateLoginData(
                        username,
                        password
                    ).perform(latestValue!!)
}

alexfacciorusso

10/18/2019, 11:09 AM

yes, that part make sense, indeed it’s what I tried to write, but the real problem is when I have to combine username and password AND the Unit when I press the login button 😄

the logic would be: whenever usernamePasswordChannel, the state changes using the data validator usecase, and when isLoggingInChannel is changed, it gets combined with usernamePasswordChannel and the proper login performs

Dominaezzz

10/18/2019, 11:20 AM

the state changes using the data validator usecase

Where is this in your code?

alexfacciorusso

10/18/2019, 11:21 AM

`validateLoginDataUseCase.validateLoginData(...)`is when the data is validated, and

performLoginUseCase.login(...)

is when the login is performed

Adam Powell

10/18/2019, 1:20 PM

You probably don't want consume for the channels since it will ensure the channel is closed when those blocks exit. You want this LiveData to be able to become active/inactive multiple times.

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