Estado de desplazamiento y desplazamiento programático

Sometimes you need to read how far a list has scrolled, or jump it somewhere yourself. That is the job of a scroll state. 🎚️

Create and hold a list state with rememberLazyListState, then pass it to your LazyColumn, LazyRow, or grid.

A grid uses its own holder, rememberLazyGridState. Wire it the same way to track and drive a LazyVerticalGrid.

Ask the state for firstVisibleItemIndex to know which item sits at the top of the viewport right now.

The flag isScrollInProgress tells you whether the user is actively scrolling, handy for hiding a toolbar while they move.

To snap straight to an item with no animation, call scrollToItem from a coroutine scope.

For a gentle glide instead of a jump, use animateScrollToItem. It is great for a back-to-top button.

Scrolling is a suspend operation, so it must run in a coroutine. Grab a rememberCoroutineScope to launch it from a click.

Combine the two ideas: derive a visibility flag from firstVisibleItemIndex, then animate-scroll to zero on tap.

Because the state is remembered, the scroll position survives recomposition. Use rememberSaveable variants to keep it across rotation.

The pattern is consistent: hold a scroll state, read it to react to position, and call its scroll functions to move the list yourself.

You learned to hold a scroll state, read firstVisibleItemIndex, and drive lists with scrollToItem and animateScrollToItem from a coroutine. 🚀