Transition

Class

Common
public class Transition<S>
internal constructor(
    private val transitionState: TransitionState<S>,
    @get:RestrictTo(RestrictTo.Scope.LIBRARY) public val parentTransition: Transition<*>?,
    public val label: String? = null,
)

Transition manages all the child animations on a state level. Child animations can be created in a declarative way using Transition.animateFloat, Transition.animateValue, animateColor etc. When the targetState changes, Transition will automatically start or adjust course for all its child animations to animate to the new target values defined for each animation.

After arriving at targetState, Transition will be triggered to run if any child animation changes its target value (due to their dynamic target calculation logic, such as theme-dependent values).

Secondary Constructors

@PublishedApi
internal constructor(
    transitionState: TransitionState<S>,
    label: String? = null,
) : this(transitionState, null, label)
internal constructor(
    initialState: S,
    label: String?,
) : this(MutableTransitionState(initialState), null, label)
@PublishedApi
internal constructor(
    transitionState: MutableTransitionState<S>,
    label: String? = null,
) : this(transitionState as TransitionState<S>, null, label)

Functions

@RestrictTo(RestrictTo.Scope.LIBRARY_GROUP_PREFIX)
    
    
    public fun setPlaytimeAfterInitialAndTargetStateEstablished(
        initialState: S,
        targetState: S,
        playTimeNanos: Long,
    )

This allows tools to set the transition (between initial and target state) to a specific playTimeNanos.

Note: This function is intended for tooling use only.

Caveat: Once initialState or targetState changes, it needs to take a whole composition pass for all the animations and child transitions to recompose with the new initialState and targetState. Subsequently all the animations will be updated to the given play time.

Caveat: This function puts Transition in a manual playtime setting mode. From then on the Transition will not resume normal animation runs.