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kotlinlang

Hi, I'm trying to pass a variable out of my LaunchedEffect so I can use it. I'm not sure how to accomplish that. Any ideas?

```@Composable
fun CallApi() {
    LaunchedEffect(key1 = {}, block = {
        val retrofitData = retrofitBuilder.getBooks("flower")
    })
    LazyColumn(content = {
        item {
            for (item in retrofitData.items) {
                Text(text = item.volumeInfo.title)
            }
        }
    })
}```


```The problem is getting retrofitData```

Use a `MutableState`, something like this:
```var retrofitData by remember { mutableStateOf(emptyList()) }
LaunchedEffect(retrofit) {
  retrofitData = retrofit.getBooks("flower")
}
LazyColumn(…```
Make sure to pass any dependencies used in your lambda as keys, in this case the retrofit object. This pattern is common enough that there’s a helper for it:
```val retrofitData by produceState(initialValue = emptyList(), key1 = retrofit) {
  retrofit.getBooks("flower")
}```


you'll want a `value =` in there but otherwise yes :slightly_smiling_face:

Most of this is going over my head (mostly due to me being unfamiliar/unsure of my own knowledge on LaunchedEffect)

Nat, just out of curiosity, what are you accomplishing with your code snippet here? I'm intrigued :smile:

I'm retrieving book details from the Google Books api, ie a list of book titles that match the search term "flower", and displaying it in a LazyColumn. :blush:

Why is this being done in a LaunchedEffect though? Wouldn't your ViewModel (or similar) be in charge of fetching?

The interface that does the fetching is a suspend function...

Lol, I'm not an expert at all. I'm trying to work it out myself. :wink: