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kotlinlang

Hi, I can't find how to remove a subscriber to a StateFlow since collect never terminates.  I just want to stop listening once a certain state is emitted.  Thanks
```scope.launch { stateFlow.collect { if (it is State) doWork(); /* how do i unsubscribe here? */ } }```

This should do:

```scope.launch {
    stateFlow.takeWhile { it is State }.collect { doWork() }
}```


okay I thought I tried that and transformWhile but i'll double check. I might have been blocking something and it never completed.

You may also be looking for something like:
```scope.launch {
    val item = stateFlow.first() //wait for first item
    if (item is State) {
        doWork()
    }
}```
Not really sure if the code snippet you wrote is exactly what you meant. I read that as "check the first item if work should be done and then stop listening regardless of what it is."

Ah yeah I sort of assumed an else there, but technically you're right <@U026KAV017Z>

I'm looking to listen until a state is emitted and then stop listening

so any number of emissions can be ignored until the correct state is emitted

so the takeWhile is what i was expecting but it never completed in my sample

Then I don't believe `takeWhile` is what you want here. If you want to subscribe and wait for the first item that is a `State` you should use `val state = stateFlow.first { it is State }` . Or if you want to avoid casting to `State` you could use:

```scope.launch {
    val item = stateFlow.filterIsInstance&lt;State&gt;().first()
    doWork()
}```
