Anyone familiar with MapView + AndroidView. I just...

# compose

[Colton Idle]

Anyone familiar with MapView + AndroidView. I just have a simple map, and I hit a network call to get the lat + long of 5 places. When the network call returns I add those 5 items to a

var list = mutableStateListOf<Location>()

but my map never updates until I reload that page.

I believe I'm doing everything correclty, because if I comment out my MapView code and replace it with a Column + forEach then all of my items show when the network call completes. Is there some sort of thing you need to hook into with AndroidView + mapView to have it respond to mutableState?

[Colton Idle]

Note: I'm not using the compose maps composable because it doesn't support clustering.

[Adam Powell]

@Chris Arriola might be able to help; there's really not enough info here about your own code to go on but re. Maps Compose feature support he's the expert 🙂

[Colton Idle]

Damn. Okay. I might just try to use a TextView in an Android view and see if I can make it react to changes. If so, then it's definitely map view

[yschimke]

What does your AndroidView look like? Are you setting these locations in update lambda?

[Colton Idle]

My code looks pretty much like this SO question: https://stackoverflow.com/questions/70996797/how-to-refresh-cluster-markers-on-a-map-with-jetpack-composite

[yschimke]

I suspect the mapView.getAsync(callback) isn't involved in state tracking. Try doing reads of state in the update lambda outside the getAsync call.

[yschimke]

Can you update state externally when the markers change and then read them from the update lambda before you call mapView.getAsync?

[yschimke]

Docs on this point https://developer.android.com/jetpack/compose/interop/interop-apis

AndroidView(
        modifier = Modifier.fillMaxSize(), // Occupy the max size in the Compose UI tree
        factory = { context ->
            // Creates custom view
            CustomView(context).apply {
                // Sets up listeners for View -> Compose communication
                myView.setOnClickListener {
                    selectedItem.value = 1
                }
            }
        },
        update = { view ->
            // View's been inflated or state read in this block has been updated
            // Add logic here if necessary

            // As selectedItem is read here, AndroidView will recompose
            // whenever the state changes
            // Example of Compose -> View communication
            view.coordinator.selectedItem = selectedItem.value
        }