scrollable2D

Common

Modifier in Compose Foundation

Configure touch scrolling and flinging for the UI element in both XY orientations.

Users should update their state themselves using default [Scrollable2DState] and its consumeScrollDelta callback or by implementing [Scrollable2DState] interface manually and reflect their own state in UI when using this component.

If you don't need to have fling or nested scroll support, but want to make component simply draggable, consider using [draggable2D]. If you're only interested in a single direction scroll, consider using [scrollable].

This overload provides the access to [OverscrollEffect] that defines the behaviour of the over scrolling logic. Use [androidx.compose.foundation.rememberOverscrollEffect] to create an instance of the current provided overscroll implementation.

Last updated:

Installation

dependencies {
   implementation("androidx.compose.foundation:foundation:1.9.0-alpha03")
}

Overloads

@Stable
fun Modifier.scrollable2D(
    state: Scrollable2DState,
    enabled: Boolean = true,
    overscrollEffect: OverscrollEffect? = null,
    flingBehavior: FlingBehavior? = null,
    interactionSource: MutableInteractionSource? = null
)

Parameters

namedescription
state[Scrollable2DState] state of the scrollable. Defines how scroll events will be interpreted by the user land logic and contains useful information about on-going events.
enabledwhether or not scrolling is enabled
overscrollEffecteffect to which the deltas will be fed when the scrollable have some scrolling delta left. Pass null for no overscroll. If you pass an effect you should also apply [androidx.compose.foundation.overscroll] modifier.
flingBehaviorlogic describing fling behavior when drag has finished with velocity. If null, default from [ScrollableDefaults.flingBehavior] will be used.
interactionSource[MutableInteractionSource] that will be used to emit drag events when this scrollable is being dragged.

Code Example

Scrollable2DSample

@Composable
fun Scrollable2DSample() {
    // actual composable state that we will show on UI and update in `Scrollable`
    val offset = remember { mutableStateOf(Offset.Zero) }
    Box(
        Modifier.size(150.dp)
            .scrollable2D(
                // state for Scrollable, describes how to consume scroll amount
                state =
                    rememberScrollable2DState { delta ->
                        // use the scroll data and indicate how much this element consumed.
                        // unconsumed deltas will be propagated to nested scrollables (if present)
                        offset.value = offset.value + delta // update the state
                        delta // indicate that we consumed all the pixels available
                    }
            )
            .background(Color.LightGray),
        contentAlignment = Alignment.Center
    ) {
        // Modifier.scrollable is not opinionated about its children's layouts. It will however
        // promote nested scrolling capabilities if those children also use the modifier.
        // The modifier will not change any layouts so one must handle any desired changes through
        // the delta values in the scrollable state
        Text(
            "X=${offset.value.x.roundToInt()} Y=${offset.value.y.roundToInt()}",
            style = TextStyle(fontSize = 32.sp)
        )
    }
}
by @alexstyl