EnterTransition

val None: EnterTransition

This can be used when no enter transition is desired. It can be useful in cases where there are other forms of enter animation defined indirectly for an AnimatedVisibility. e.g.The children of the AnimatedVisibility have all defined their own EnterTransition, or when the parent is fading in, etc.

protected EnterTransition()

open operator fun equals(other: Any?): Boolean

open fun hashCode(): Int

operator fun plus(enter: EnterTransition): EnterTransition

Combines different enter transitions. The order of the EnterTransitions being combined does not matter, as these EnterTransitions will start simultaneously. The order of applying transforms from these enter transitions (if defined) is: alpha and scale first, shrink or expand, then slide.

import androidx.compose.animation.AnimatedVisibility
import androidx.compose.animation.expandVertically
import androidx.compose.animation.fadeIn
import androidx.compose.animation.fadeOut
import androidx.compose.animation.scaleIn
import androidx.compose.animation.scaleOut
import androidx.compose.animation.shrinkVertically
import androidx.compose.animation.slideIn
import androidx.compose.animation.slideInVertically
import androidx.compose.animation.slideOut
import androidx.compose.animation.slideOutVertically
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.requiredHeight
import androidx.compose.material.Text
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.TransformOrigin
import androidx.compose.ui.unit.dp

var visible by remember { mutableStateOf(true) }
AnimatedVisibility(
    visible = visible,
    enter =
        slideInVertically(
            // Start the slide from 40 (pixels) above where the content is supposed to go, to
            // produce a parallax effect
            initialOffsetY = { -40 }
        ) +
            expandVertically(expandFrom = Alignment.Top) +
            scaleIn(
                // Animate scale from 0f to 1f using the top center as the pivot point.
                transformOrigin = TransformOrigin(0.5f, 0f)
            ) +
            fadeIn(initialAlpha = 0.3f),
    exit = slideOutVertically() + shrinkVertically() + fadeOut() + scaleOut(targetScale = 1.2f)
) {
    // Content that needs to appear/disappear goes here:
    Text("Content to appear/disappear", Modifier.fillMaxWidth().requiredHeight(200.dp))
}

open fun toString(): String

infix fun EnterTransition.togetherWith(exit: ExitTransition): ContentTransform

This creates a ContentTransform using the provided EnterTransition and exit, where the enter and exit transition will be running simultaneously. For example:

import androidx.compose.animation.AnimatedContent
import androidx.compose.animation.AnimatedContentTransitionScope
import androidx.compose.animation.ContentTransform
import androidx.compose.animation.SizeTransform
import androidx.compose.animation.core.keyframes
import androidx.compose.animation.core.tween
import androidx.compose.animation.fadeIn
import androidx.compose.animation.fadeOut
import androidx.compose.animation.togetherWith
import androidx.compose.ui.unit.IntSize

// enum class CartState { Expanded, Collapsed }
val transitionSpec: AnimatedContentTransitionScope<CartState>.() -> ContentTransform = {
    // Fade in with a delay so that it starts after fade out
    fadeIn(animationSpec = tween(150, delayMillis = 150))
        .togetherWith(fadeOut(animationSpec = tween(150)))
        .using(
            SizeTransform { initialSize, targetSize ->
                // Using different SizeTransform for different state change
                if (CartState.Collapsed isTransitioningTo CartState.Expanded) {
                    keyframes {
                        durationMillis = 500
                        // Animate to full target width and by 200px in height at 150ms
                        IntSize(targetSize.width, initialSize.height + 200) at 150
                    }
                } else {
                    keyframes {
                        durationMillis = 500
                        // Animate 1/2 the height without changing the width at 150ms.
                        // The width and rest of the height will be animated in the
                        // timeframe between 150ms and duration (i.e. 500ms)
                        IntSize(
                            initialSize.width,
                            (initialSize.height + targetSize.height) / 2
                        ) at 150
                    }
                }
            }
        )
}

@ExperimentalAnimationApi
infix fun EnterTransition.with(exit: ExitTransition): ContentTransform