zsoltk

val cards = Cards(
    initialItems = listOf(
        Routing.ProfileCard(0, "Lara"),    // Will be top
        Routing.ProfileCard(1, "Kate"),    // Will be bottom
        Routing.ProfileCard(2, "Brad"),    // Queued = 0
        Routing.ProfileCard(3, "Megan"),   // ...etc.
        Routing.ProfileCard(4, "Michael"),
        Routing.ProfileCard(0, "Lara"),
        Routing.ProfileCard(1, "Kate"),
        Routing.ProfileCard(2, "Brad"),

zsoltk

lifecycle.coroutineScope.launchWhenStarted {
    delay(1000)
    repeat(3) {
        delay(2000)
        cards.indicateLike()
        delay(1000)
        cards.indicatePass()
        delay(1000)
        cards.votePass()
        delay(1000)

zsoltk

class CardsTransitionHandler<T>(
    private val transitionSpec: TransitionSpec<Cards.State, Float> = { 
        spring(stiffness = Spring.StiffnessVeryLow) 
    }
) : ModifierTransitionHandler<T, Cards.State>() {
 
    private fun Cards.State.toProps() =
        when (this) {
            is Queued -> queued
            is Bottom -> bottom

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private fun Cards.State.toProps() =
    when (this) {
        is Queued -> queued
        is Bottom -> bottom
        is Top -> top
        is VoteLike -> voteLike
        is VotePass -> votePass
    }

zsoltk

// Scaled down to 0% (not visible)
private val queued = Props(
    scale = 0f,
)

// Scaled down to 85%
private val bottom = Props(
    scale = 0.85f,
)

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data class Props(
    val offsetX: Dp = 0.dp,
    val scale: Float = 1f,
    val rotationZ: Float = 0f,
    val zIndex: Float = 0f,
)

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internal class PromoteAll<T : Any> : CardsOperation<T> {

    override fun invoke(elements: CardsElements<T>): CardsElements<T> =
        elements.map {
            it.transitionTo(
                // This uses State.next() we defined earlier:
                newTargetState = it.targetState.next(),
                operation = this
            )
        }

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class VoteLike<T : Any> internal constructor() : CardsOperation<T> {

    // Returns a modified list of elements with new target states applied
    override fun invoke(elements: CardsElements<T>): CardsElements<T> =
        elements.map { element ->
            if (element.targetState == Cards.State.Top) {
                element.transitionTo(
                    newTargetState = Cards.State.VoteLike,
                    operation = this
                )

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class Cards<T : Any>(
    initialItems: List<T> = listOf(),
) : BaseNavModel<T, State>(
    screenResolver = CardsOnScreenResolver,  // <- What's on screen?
    finalStates = setOf(VoteLike, VotePass), // <- What's destroyed?
    savedStateMap = null
)

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internal object CardsOnScreenResolver : OnScreenStateResolver<State> {
    override fun isOnScreen(state: State): Boolean =
        when (state) {
            is State.Bottom,
            is State.Top -> true
            is State.Queued,
            is State.VoteLike,
            is State.VotePass -> false
        }
}