ScalingLazyListState

Class

Android

Deprecated Was moved to androidx.wear.compose.foundation.lazy package. Please use it instead

public class ScalingLazyListState
constructor(
    private var initialCenterItemIndex: Int = 1,
    private var initialCenterItemScrollOffset: Int = 0,
) : ScrollableState

A state object that can be hoisted to control and observe scrolling.

In most cases, this will be created via rememberScalingLazyListState.

If the developer wants custom control over position and spacing they can switch off autoCentering and provide contentPadding.

Note that it is not always possible for the values provided by initialCenterItemIndex and initialCenterItemScrollOffset to be honored, e.g. If initialCenterItemIndex is set to a value larger than the number of items initially in the list, or to an index that can not be placed in the middle of the screen due to the contentPadding or autoCentering properties provided to the ScalingLazyColumn. After the ScalingLazyColumn is initially drawn the actual values for the centerItemIndex and centerItemScrollOffset can be read from the state.

Parameters


initialCenterItemIndex	the initial value for `ScalingLazyListState.centerItemIndex`, defaults to 1. This will place the 2nd list item (index == 1) in the center of the viewport and the first item (index == 0) before it.
initialCenterItemScrollOffset	the initial value for `ScalingLazyListState.centerItemScrollOffset`

Functions

public suspend fun scrollToItem(
        /*@IntRange(from = 0)*/
        index: Int,
        /*@IntRange(from = 0)*/
        scrollOffset: Int = 0,
    )

Instantly brings the item at index to the center of the viewport and positions it based on the anchorType and applies the scrollOffset pixels.

Parameters


index	the index to which to scroll. Must be non-negative.
scrollOffset	the offset that the item should end up after the scroll. Note that positive offset refers to forward scroll, so in a top-to-bottom list, positive offset will scroll the item further upward (taking it partly offscreen).

public suspend fun animateScrollToItem(
        /*@IntRange(from = 0)*/
        index: Int,
        /*@IntRange(from = 0)*/
        scrollOffset: Int = 0,
    )

Animate (smooth scroll) the given item at index to the center of the viewport and position it based on the anchorType and applies the scrollOffset pixels.

Parameters


index	the index to which to scroll. Must be non-negative.
scrollOffset	the offset that the item should end up after the scroll (same as `scrollToItem`) - note that positive offset refers to forward scroll, so in a top-to-bottom list, positive offset will scroll the item further upward (taking it partly offscreen)

Companion Object

Properties

Android

public val Saver: Saver<ScalingLazyListState, Any>

The default Saver implementation for ScalingLazyListState.