[STL] Respect animationSpec for predictive back transition in STL (fefa3e63) · Commits · e / os / android_frameworks_base

packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/PredictiveBackHandler.kt

+10 −9

Original line number	Diff line number	Diff line
		@@ -18,7 +18,7 @@ package com.android.compose.animation.scene

		import androidx.activity.BackEventCompat
		import androidx.activity.compose.PredictiveBackHandler
		import androidx.compose.animation.core.spring
		import androidx.compose.animation.core.AnimationSpec
		import androidx.compose.foundation.gestures.Orientation
		import androidx.compose.runtime.Composable
		import kotlin.coroutines.cancellation.CancellationException
		@@ -62,7 +62,7 @@ private suspend fun <T : ContentKey> animate(
		animation: SwipeAnimation<T>,
		progress: Flow<BackEventCompat>,
		) {
		fun animateOffset(targetContent: T) {
		fun animateOffset(targetContent: T, spec: AnimationSpec<Float>? = null) {
		if (
		layoutImpl.state.transitionState != animation.contentTransition \|\| animation.isFinishing
		) {
		@@ -72,12 +72,7 @@ private suspend fun <T : ContentKey> animate(
		animation.animateOffset(
		initialVelocity = 0f,
		targetContent = targetContent,

		// TODO(b/350705972): Allow to customize or reuse the same customization endpoints as
		// the normal swipe transitions. We can't just reuse them here because other swipe
		// transitions animate pixels while this transition animates progress, so the visibility
		// thresholds will be completely different.
		spec = spring(),
		spec = spec,
		)
		}

		@@ -86,9 +81,15 @@ private suspend fun <T : ContentKey> animate(
		progress.collect { backEvent -> animation.dragOffset = backEvent.progress }

		// Back gesture successful.
		animateOffset(animation.toContent)
		animateOffset(
		animation.toContent,
		animation.contentTransition.transformationSpec.progressSpec
		)
		} catch (e: CancellationException) {
		// Back gesture cancelled.
		// If the back gesture is cancelled, the progress is animated back to 0f by the system.
		// Since the remaining change in progress is usually very small, the progressSpec is omitted
		// and the default spring spec used instead.
		animateOffset(animation.fromContent)
		}
		}

packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/SwipeAnimation.kt

+2 −2

Original line number	Diff line number	Diff line
		@@ -17,8 +17,8 @@
		package com.android.compose.animation.scene

		import androidx.compose.animation.core.Animatable
		import androidx.compose.animation.core.AnimationSpec
		import androidx.compose.animation.core.AnimationVector1D
		import androidx.compose.animation.core.SpringSpec
		import androidx.compose.foundation.gestures.Orientation
		import androidx.compose.runtime.getValue
		import androidx.compose.runtime.mutableFloatStateOf
		@@ -320,7 +320,7 @@ internal class SwipeAnimation<T : ContentKey>(
		fun animateOffset(
		initialVelocity: Float,
		targetContent: T,
		spec: SpringSpec<Float>? = null,
		spec: AnimationSpec<Float>? = null,
		): OffsetAnimation {
		val initialProgress = progress
		// Skip the animation if we have already reached the target content and the overscroll does

packages/SystemUI/compose/scene/tests/src/com/android/compose/animation/scene/PredictiveBackHandlerTest.kt

+34 −1

Original line number	Diff line number	Diff line
		@@ -18,6 +18,8 @@ package com.android.compose.animation.scene

		import androidx.activity.BackEventCompat
		import androidx.activity.ComponentActivity
		import androidx.compose.animation.core.LinearEasing
		import androidx.compose.animation.core.tween
		import androidx.compose.foundation.layout.Box
		import androidx.compose.foundation.layout.fillMaxSize
		import androidx.compose.foundation.layout.size
		@@ -65,7 +67,23 @@ class PredictiveBackHandlerTest {

		@Test
		fun testPredictiveBack() {
		val layoutState = rule.runOnUiThread { MutableSceneTransitionLayoutState(SceneA) }
		val transitionFrames = 2
		val layoutState =
		rule.runOnUiThread {
		MutableSceneTransitionLayoutState(
		SceneA,
		transitions =
		transitions {
		from(SceneA, to = SceneB) {
		spec =
		tween(
		durationMillis = transitionFrames * 16,
		easing = LinearEasing
		)
		}
		}
		)
		}
		rule.setContent {
		SceneTransitionLayout(layoutState) {
		scene(SceneA, mapOf(Back to SceneB)) { Box(Modifier.fillMaxSize()) }
		@@ -94,12 +112,27 @@ class PredictiveBackHandlerTest {
		assertThat(layoutState.transitionState).hasCurrentScene(SceneA)
		assertThat(layoutState.transitionState).isIdle()

		rule.mainClock.autoAdvance = false

		// Start again and commit it.
		rule.runOnUiThread {
		dispatcher.dispatchOnBackStarted(backEvent())
		dispatcher.dispatchOnBackProgressed(backEvent(progress = 0.4f))
		dispatcher.onBackPressed()
		}
		rule.mainClock.advanceTimeByFrame()
		rule.waitForIdle()
		val transition2 = assertThat(layoutState.transitionState).isSceneTransition()
		// verify that transition picks up progress from preview
		assertThat(transition2).hasProgress(0.4f, tolerance = 0.0001f)

		rule.mainClock.advanceTimeByFrame()
		rule.waitForIdle()
		// verify that transition is half way between preview-end-state (0.4f) and target-state (1f)
		// after one frame
		assertThat(transition2).hasProgress(0.7f, tolerance = 0.0001f)

		rule.mainClock.autoAdvance = true
		rule.waitForIdle()
		assertThat(layoutState.transitionState).hasCurrentScene(SceneB)
		assertThat(layoutState.transitionState).isIdle()