DecayAnimationSpec

Artifact: androidx.compose.animation:animation-core

View Source

Added in 1.0.0

Common/All

• Cmn

  interface DecayAnimationSpec<T : Any?>

---

DecayAnimationSpec stores the specification of an animation, including 1) the data type to be animated, and 2) the animation configuration (i.e. VectorizedDecayAnimationSpec) that will be used once the data (of type T) has been converted to AnimationVector.

Any type T can be animated by the system as long as a TwoWayConverter is supplied to convert the data type T from and to an AnimationVector. There are a number of converters available out of the box. For example, to animate androidx.compose.ui.unit.IntOffset the system uses IntOffset.VectorConverter to convert the object to AnimationVector2D, so that both x and y dimensions are animated independently with separate velocity tracking. This enables multidimensional objects to be animated in a true multi-dimensional way. It is particularly useful for smoothly handling animation interruptions (such as when the target changes during the animation).

Summary

Public functions
VectorizedDecayAnimationSpec<V>	<V : AnimationVector> vectorize(typeConverter: TwoWayConverter<T, V>) Creates a VectorizedDecayAnimationSpec with the given TwoWayConverter.	Cmn

Extension functions
Float	DecayAnimationSpec<Float>.calculateTargetValue(     initialValue: Float,     initialVelocity: Float ) Calculates the target value of a Float decay animation based on the initialValue and initialVelocity.	Cmn
T	<T : Any?, V : AnimationVector> DecayAnimationSpec<T>.calculateTargetValue(     typeConverter: TwoWayConverter<T, V>,     initialValue: T,     initialVelocity: T ) Calculates the target value of a decay animation based on the initialValue and initialVelocity, and the typeConverter that converts the given type T to AnimationVector.	Cmn

Public functions

vectorize

Cmn

Added in 1.0.0

fun <V : AnimationVector> vectorize(typeConverter: TwoWayConverter<T, V>): VectorizedDecayAnimationSpec<V>

Creates a VectorizedDecayAnimationSpec with the given TwoWayConverter.

The underlying animation system operates on AnimationVectors. T will be converted to AnimationVector to animate. VectorizedDecayAnimationSpec describes how the converted AnimationVector should be animated.

Parameters
typeConverter: TwoWayConverter<T, V>	converts the type T from and to AnimationVector type

Extension functions

calculateTargetValue

Cmn

Artifact: androidx.compose.animation:animation-core

View Source

fun DecayAnimationSpec<Float>.calculateTargetValue(
    initialValue: Float,
    initialVelocity: Float
): Float

Calculates the target value of a Float decay animation based on the initialValue and initialVelocity.

Returns
Float	target value where the animation will come to a natural stop

calculateTargetValue

Cmn

Artifact: androidx.compose.animation:animation-core

View Source

fun <T : Any?, V : AnimationVector> DecayAnimationSpec<T>.calculateTargetValue(
    typeConverter: TwoWayConverter<T, V>,
    initialValue: T,
    initialVelocity: T
): T

Calculates the target value of a decay animation based on the initialValue and initialVelocity, and the typeConverter that converts the given type T to AnimationVector.

Returns
T	target value where the animation will come to a natural stop