Ok. I'm dumb as a stump and can't get a list to u...

# compose-desktop

[Trevor Merritt]

Ok. I'm dumb as a stump and can't get a list to update. I've got a window with a lazycolumnfor, but when I update the remembered value, the ui doesn't update. im expecting theres a onUpdate or similar I'm missing. Can someone point me to a sample with a CRUD list?

[theapache64]

Can u paste the code here?

[theapache64]

BTW, there's no onUpdate kinda thing here.

[Trevor Merritt]

Box(modifier = Modifier.fillMaxSize())
{
    LazyColumnFor(
        modifier = Modifier.fillMaxSize(),
        items  = entries,
        state = scrollState,
        itemContent = { Text(it) }
    )
    VerticalScrollbar(ScrollbarAdapter(scrollState, entries.count(), 1f))
}

[Trevor Merritt]

this function is being passed a List<String> of entries

[theapache64]

and where do you update the value?

[Trevor Merritt]

im seeing that im updating a copy of the object. let me sort that out and see if its a monday morning thing. 🙂

[Olivier]

I think you could also check the version of Java you're using. While I used 8 the UI doesn't update every time, but when I moved to 15, everything started to work.

[Trevor Merritt]

I am using openjdk15 good to know though.

[jim]

I find it highly unlikely that the JVM version would be causing the app to behave differently, but if the JVM version is causing the code to behave differently, that is a huge bug, please file a bug with a minimal repro.

[jim]

Also, if you are mutating the list, be sure you are using a SnapshotStateList (probably via mutableStateListOf. Or ensure your list is immutable, but that is not recommended if the list is large as it will be more expensive to recompose on each change.

[Trevor Merritt]

I've now had a chance to go back and apply the changes and use SnapshotStateList as suggested by Jim. I now have a working example and am back in motion making progress. Thanks for your help guys!