does collecting two flows inside the same coroutineScope inf

Question

does collecting two flows inside the same coroutineScope influence each other when the coroutine context is a `SupervisorJob`

Remy Benza · Answer

example `val scope = CoroutineScope SupervisorJob + Dispatchers Main ` `scope launch ` `flow1 collect code ` `flow2 collect code ` ` `

Remy Benza · Answer

if the collection of flow1 fails does flow2 run normally I think I would because of the SupervisorJob context But I ve experience flow2 does not get collected

Natsuki(开元米粉实力代购) · Answer

there s nothing to do with `SupervisorJob` that s becoz in semantic flow is cold thus when runs `flows2 collect` that indicate `flow1 collect` is done use `launchIn` or fire another `launch` with each collect

KamilH · Answer

`collect` is a suspend function so it suspends until `flow1` finishes It s always better to use `onEach` + `launchIn` combination

Remy Benza · Answer

can you provide a snippet how would you do this

KamilH · Answer

```flow1 onEach handle new value here launchIn scope scope launch flow1 collect handle new value here ```

KamilH · Answer

These two are doing the same lets you launch new coroutine and collect items

KamilH · Answer

The difference is that you can do this ```flow1 onEach launchIn viewModelScope flow2 onEach launchIn viewModelScope ``` without waiting for flow1 to finish while here ```viewModelScope launch flow1 collect flow2 collect ``` `flow2 collect` will be called only after `flow1` finished

Remy Benza · Answer

thnx and does the fact you re using a `Job`or `SupervisorJob`for the context play a role in the outcome

KamilH · Answer

In this context no If I m not mistaken it would make a difference only when one of them collections throw an exception In `Job` case whole job would be cancelled while in `SupervisorJob` it wouldn t

dewildte · Answer

Here you have two flows in a single coroutine If there is an uncaught exception thrown then the coroutine it is in will be canceled and then the scope the coroutine is in will also be canceled If the scope has a `SupervisorJob` then the scope will not be canceled

dewildte · Answer

As for the collection of the two flows influencing the other the answer is yes if they are collected in the same coroutine

dewildte · Answer

` collect` does not start a new coroutine it just suspends the current coroutine until the collection is complete

Remy Benza · Answer

thnx for your explanation