Problem: Click callback uses outdated data about mapcompose HOT 5 CLOSED

You probably need to update the callback when your state changes. Try with:

@Composable
fun MyMapComposable(modifier: Modifier = Modifier, myData: MyData, mapState: MapState) {
    LaunchedEffect(myData) {
        mapState.onMarkerClick { id, x, y ->
            Log.d("Bug", "my marker state: ${myData.someList.size}")
        }
    }

    MapUI(modifier, state = mapState)
}

from mapcompose.

yep, that works too - but i'm not quite sure why i would need to do that .

shouldn't the lambda access the updated data anyways? (data is correctly updated outside of the callback)

from mapcompose.

That's because LaunchedEffect can take keys as parameters, and whenever one keys changes of value, the composable block is recomposed. By using LaunchedEffect(Unit){..}, you are actually capturing the initial value of your state.

from mapcompose.

thanks, i thought i'm aware of the concept of LaunchedEffect but assumed that the created callback (lambda) would still access the current state - seems it also captures a snapshot of the current state -interesting.

from mapcompose.

Another approach is to call a method from the view-model from the lambda, passing id, x and y values. Since the view-model has all necessary data, you can do necessary operations and state changes from there, without having to worry about updating the lambda.

from mapcompose.