SwipeableState

Class

Common

Deprecated SwipeableDeprecation

@ExperimentalMaterialApi
open class SwipeableState<T>(
    initialValue: T,
    internal val animationSpec: AnimationSpec<Float> = AnimationSpec,
    internal val confirmStateChange: (newValue: T) -> Boolean = { true },
)

State of the swipeable modifier.

This contains necessary information about any ongoing swipe or animation and provides methods to change the state either immediately or by starting an animation. To create and remember a SwipeableState with the default animation clock, use rememberSwipeableState.

Parameters

initialValueThe initial value of the state.
animationSpecThe default animation that will be used to animate to a new state.
confirmStateChangeOptional callback invoked to confirm or veto a pending state change.

Properties

Common
var currentValue: T

The current value of the state.

If no swipe or animation is in progress, this corresponds to the anchor at which the swipeable is currently settled. If a swipe or animation is in progress, this corresponds the last anchor at which the swipeable was settled before the swipe or animation started.

Common
var isAnimationRunning: Boolean

Whether the state is currently animating.

Common
val offset: State<Float>

The current position (in pixels) of the swipeable.

You should use this state to offset your content accordingly. The recommended way is to use Modifier.offsetPx. This includes the resistance by default, if resistance is enabled.

Common
val overflow: State<Float>

The amount by which the swipeable has been swiped past its bounds.

Common
@ExperimentalMaterialApi
val targetValue: T

The target value of the state.

If a swipe is in progress, this is the value that the swipeable would animate to if the swipe finished. If an animation is running, this is the target value of that animation. Finally, if no swipe or animation is in progress, this is the same as the currentValue.

Common
@ExperimentalMaterialApi
val progress: SwipeProgress<T>

Information about the ongoing swipe or animation, if any. See SwipeProgress for details.

If no swipe or animation is in progress, this returns SwipeProgress(value, value, 1f).

Common
@ExperimentalMaterialApi
val direction: Float

The direction in which the swipeable is moving, relative to the current currentValue.

This will be either 1f if it is is moving from left to right or top to bottom, -1f if it is moving from right to left or bottom to top, or 0f if no swipe or animation is in progress.

Functions

@ExperimentalMaterialApi
    suspend fun snapTo(targetValue: T)

Set the state without any animation and suspend until it's set

Parameters

targetValueThe new target value to set currentValue to.
@ExperimentalMaterialApi
    suspend fun animateTo(targetValue: T, anim: AnimationSpec<Float> = animationSpec)

Set the state to the target value by starting an animation.

Parameters

targetValueThe new value to animate to.
animThe animation that will be used to animate to the new value.
suspend fun performFling(velocity: Float)

Perform fling with settling to one of the anchors which is determined by the given velocity. Fling with settling swipeable will always consume all the velocity provided since it will settle at the anchor.

In general cases, swipeable flings by itself when being swiped. This method is to be used for nested scroll logic that wraps the swipeable. In nested scroll developer may want to trigger settling fling when the child scroll container reaches the bound.

Parameters

velocityvelocity to fling and settle with

Returns

the reason fling ended
fun performDrag(delta: Float): Float

Force swipeable to consume drag delta provided from outside of the regular swipeable gesture flow.

Note: This method performs generic drag and it won't settle to any particular anchor, * leaving swipeable in between anchors. When done dragging, performFling must be called as well to ensure swipeable will settle at the anchor.

In general cases, swipeable drags by itself when being swiped. This method is to be used for nested scroll logic that wraps the swipeable. In nested scroll developer may want to force drag when the child scroll container reaches the bound.

Parameters

deltadelta in pixels to drag by

Returns

the amount of delta consumed

Companion Object

Methods

Common
fun <T : Any> Saver(
            animationSpec: AnimationSpec<Float>,
            confirmStateChange: (T) -> Boolean,
        ) =
            Saver<SwipeableState<T>, T>(
                save = { it.currentValue },
                restore = { SwipeableState(it, animationSpec, confirmStateChange) },
            )

The default Saver implementation for SwipeableState.