How can the parent composable communicate events to the child composable? For example, I want to scr...

# compose

[allan.conda]

How can the parent composable communicate events to the child composable?
For example, I want to scroll-to-top the start destination when the bottom bar is tapped.

[Yashwant Gowla]

Using states in compose
https://developer.android.com/jetpack/compose/state#state-in-composables

[Filip Wiesner]

Ideally the events should go only up and state go down in the view hierarchy.
Try reading specifically the State hoisting chapter in the documentation YG6008 linked.

[Yashwant Gowla]

@Filip Wiesner 👍

[Filip Wiesner]

But if have to do it like this, then you can always pass something like listener callback or some other thing that the child will listen to 🤷 But I would advice against doing that.
Or if you have a ViewModel that you pass to this child, you could pipe the event through it.

[Ben Trengrove [G]]

Hoist a state holder that has a function in it to scroll to the top. For example how LazyList does it

[allan.conda]

Hoist a state holder that has a function in it to scroll to the top. For example how LazyList does it

Ah, that’s what I thought too, just a bit weird to hoist the lazyListState up to the root 😄. I have a feeling it would break the list state somehow too, but I could try a hoist separate state just for scrolling up.

Currently we provide a Scroll event flow in a repository, but I don’t like that we have scroll events at that layer.