scrollable
fun Modifier.scrollable(
state: ScrollableState,
orientation: Orientation,
enabled: Boolean = true,
reverseDirection: Boolean = false,
flingBehavior: FlingBehavior? = null,
interactionSource: MutableInteractionSource? = null,
): Modifier
Configure touch scrolling and flinging for the UI element in a single Orientation
.
Users should update their state themselves using default ScrollableState
and its
consumeScrollDelta
callback or by implementing ScrollableState
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 draggable
.
Parameters
state | ScrollableState state of the scrollable. Defines how scroll events will be interpreted by the user land logic and contains useful information about on-going events. |
orientation | orientation of the scrolling |
enabled | whether or not scrolling in enabled |
reverseDirection | reverse the direction of the scroll, so top to bottom scroll will behave like bottom to top and left to right will behave like right to left. |
flingBehavior | logic 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. |
fun Modifier.scrollable(
state: ScrollableState,
orientation: Orientation,
overscrollEffect: OverscrollEffect?,
enabled: Boolean = true,
reverseDirection: Boolean = false,
flingBehavior: FlingBehavior? = null,
interactionSource: MutableInteractionSource? = null,
bringIntoViewSpec: BringIntoViewSpec? = null,
) =
this then
ScrollableElement(
state,
orientation,
overscrollEffect,
enabled,
reverseDirection,
flingBehavior,
interactionSource,
bringIntoViewSpec,
)
Configure touch scrolling and flinging for the UI element in a single Orientation
.
Users should update their state themselves using default ScrollableState
and its
consumeScrollDelta
callback or by implementing ScrollableState
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 draggable
.
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.
Parameters
state | ScrollableState state of the scrollable. Defines how scroll events will be interpreted by the user land logic and contains useful information about on-going events. |
orientation | orientation of the scrolling |
overscrollEffect | effect 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. |
enabled | whether or not scrolling in enabled |
reverseDirection | reverse the direction of the scroll, so top to bottom scroll will behave like bottom to top and left to right will behave like right to left. |
flingBehavior | logic 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. |
bringIntoViewSpec | The configuration that this scrollable should use to perform scrolling when scroll requests are received from the focus system. If null is provided the system will use the behavior provided by LocalBringIntoViewSpec which by default has a platform dependent implementation. |
Code Examples
ScrollableSample
@Composable
fun ScrollableSample() {
// actual composable state that we will show on UI and update in `Scrollable`
val offset = remember { mutableStateOf(0f) }
Box(
Modifier.size(150.dp)
.scrollable(
orientation = Orientation.Vertical,
// state for Scrollable, describes how consume scroll amount
state =
rememberScrollableState { 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(offset.value.roundToInt().toString(), style = TextStyle(fontSize = 32.sp))
}
}