Remove interception capabilities in STL drag handler (32af9bf7) · Commits · e / os / android_frameworks_base

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

+36 −191

Original line number	Diff line number	Diff line
		@@ -14,8 +14,6 @@
		* limitations under the License.
		*/

		@file:Suppress("NOTHING_TO_INLINE")

		package com.android.compose.animation.scene

		import androidx.compose.foundation.gestures.Orientation
		@@ -97,68 +95,11 @@ internal class DraggableHandlerImpl(
		internal val positionalThreshold
		get() = with(layoutImpl.density) { 56.dp.toPx() }

		/**
		* Whether we should immediately intercept a gesture.
		*
		* Note: if this returns true, then [onDragStarted] will be called with overSlop equal to 0f,
		* indicating that the transition should be intercepted.
		*/
		internal fun shouldImmediatelyIntercept(pointersDown: PointersInfo.PointersDown?): Boolean {
		// We don't intercept the touch if we are not currently driving the transition.
		val dragController = dragController
		if (dragController?.isDrivingTransition != true) {
		return false
		}

		val swipeAnimation = dragController.swipeAnimation

		// Only intercept the current transition if one of the 2 swipes results is also a transition
		// between the same pair of contents.
		val swipes = computeSwipes(pointersDown)
		val fromContent = layoutImpl.content(swipeAnimation.currentContent)
		val (upOrLeft, downOrRight) = swipes.computeSwipesResults(fromContent)
		val currentScene = layoutImpl.state.currentScene
		val contentTransition = swipeAnimation.contentTransition
		return (upOrLeft != null &&
		contentTransition.isTransitioningBetween(
		fromContent.key,
		upOrLeft.toContent(currentScene),
		)) \|\|
		(downOrRight != null &&
		contentTransition.isTransitioningBetween(
		fromContent.key,
		downOrRight.toContent(currentScene),
		))
		}

		override fun onDragStarted(
		pointersDown: PointersInfo.PointersDown?,
		overSlop: Float,
		): DragController {
		if (overSlop == 0f) {
		val oldDragController = dragController
		check(oldDragController != null && oldDragController.isDrivingTransition) {
		val isActive = oldDragController?.isDrivingTransition
		"onDragStarted(overSlop=0f) requires an active dragController, but was $isActive"
		}

		// This [transition] was already driving the animation: simply take over it.
		// Stop animating and start from the current offset.
		val oldSwipeAnimation = oldDragController.swipeAnimation

		// We need to recompute the swipe results since this is a new gesture, and the
		// fromScene.userActions may have changed.
		val swipes = oldDragController.swipes
		swipes.updateSwipesResults(
		fromContent = layoutImpl.content(oldSwipeAnimation.fromContent)
		)

		// A new gesture should always create a new SwipeAnimation. This way there cannot be
		// different gestures controlling the same transition.
		val swipeAnimation = createSwipeAnimation(oldSwipeAnimation)
		return updateDragController(swipes, swipeAnimation)
		}

		check(overSlop != 0f)
		val swipes = computeSwipes(pointersDown)
		val fromContent = layoutImpl.contentForUserActions()

		@@ -196,7 +137,7 @@ internal class DraggableHandlerImpl(
		return createSwipeAnimation(layoutImpl, result, isUpOrLeft, orientation)
		}

		internal fun resolveSwipeSource(startedPosition: Offset): SwipeSource.Resolved? {
		private fun resolveSwipeSource(startedPosition: Offset): SwipeSource.Resolved? {
		return layoutImpl.swipeSourceDetector.source(
		layoutSize = layoutImpl.lastSize,
		position = startedPosition.round(),
		@@ -291,71 +232,25 @@ private class DragControllerImpl(
		return 0f
		}

		val toContent = swipeAnimation.toContent
		val distance = swipeAnimation.distance()
		val previousOffset = swipeAnimation.dragOffset
		val desiredOffset = previousOffset + delta

		fun hasReachedToSceneUpOrLeft() =
		distance < 0 &&
		desiredOffset <= distance &&
		swipes.upOrLeftResult?.toContent(layoutState.currentScene) == toContent

		fun hasReachedToSceneDownOrRight() =
		distance > 0 &&
		desiredOffset >= distance &&
		swipes.downOrRightResult?.toContent(layoutState.currentScene) == toContent

		// Considering accelerated swipe: Change fromContent in the case where the user quickly
		// swiped multiple times in the same direction to accelerate the transition from A => B then
		// B => C.
		//
		// TODO(b/290184746): the second drag needs to pass B to work. Add support for flinging
		// twice before B has been reached
		val hasReachedToContent =
		swipeAnimation.currentContent == toContent &&
		(hasReachedToSceneUpOrLeft() \|\| hasReachedToSceneDownOrRight())

		val fromContent: ContentKey
		val currentTransitionOffset: Float
		val newOffset: Float
		val consumedDelta: Float
		if (hasReachedToContent) {
		// The new transition will start from the current toContent.
		fromContent = toContent

		// The current transition is completed (we have reached the full swipe distance).
		currentTransitionOffset = distance

		// The next transition will start with the remaining offset.
		newOffset = desiredOffset - distance
		consumedDelta = delta
		} else {
		fromContent = swipeAnimation.fromContent
		val desiredProgress = swipeAnimation.computeProgress(desiredOffset)

		// Note: the distance could be negative if fromContent is above or to the left of
		// toContent.
		currentTransitionOffset =
		val newOffset =
		when {
		distance == DistanceUnspecified \|\|
		swipeAnimation.contentTransition.isWithinProgressRange(desiredProgress) ->
		desiredOffset

		distance > 0f -> desiredOffset.fastCoerceIn(0f, distance)
		else -> desiredOffset.fastCoerceIn(distance, 0f)
		}

		// If there is a new transition, we will use the same offset
		newOffset = currentTransitionOffset
		consumedDelta = newOffset - previousOffset
		}

		swipeAnimation.dragOffset = currentTransitionOffset
		val consumedDelta = newOffset - previousOffset

		if (hasReachedToContent) {
		swipes.updateSwipesResults(draggableHandler.layoutImpl.content(fromContent))
		}
		swipeAnimation.dragOffset = newOffset
		val result = swipes.findUserActionResult(directionOffset = newOffset)

		if (result == null) {
		@@ -372,13 +267,12 @@ private class DragControllerImpl(

		val needNewTransition =
		!currentTransitionIrreversible &&
		(hasReachedToContent \|\|
		result.toContent(layoutState.currentScene) != swipeAnimation.toContent \|\|
		(result.toContent(layoutState.currentScene) != swipeAnimation.toContent \|\|
		result.transitionKey != swipeAnimation.contentTransition.key)

		if (needNewTransition) {
		// Make sure the current transition will finish to the right current scene.
		swipeAnimation.currentContent = fromContent
		swipeAnimation.currentContent = swipeAnimation.fromContent

		val newSwipeAnimation = draggableHandler.createSwipeAnimation(swipes, result)
		newSwipeAnimation.dragOffset = newOffset
		@@ -499,7 +393,9 @@ internal class Swipes(val upOrLeft: Swipe.Resolved, val downOrRight: Swipe.Resol
		var upOrLeftResult: UserActionResult? = null
		var downOrRightResult: UserActionResult? = null

		fun computeSwipesResults(fromContent: Content): Pair<UserActionResult?, UserActionResult?> {
		private fun computeSwipesResults(
		fromContent: Content
		): Pair<UserActionResult?, UserActionResult?> {
		val upOrLeftResult = fromContent.findActionResultBestMatch(swipe = upOrLeft)
		val downOrRightResult = fromContent.findActionResultBestMatch(swipe = downOrRight)
		return upOrLeftResult to downOrRightResult
		@@ -564,48 +460,9 @@ internal class NestedScrollHandlerImpl(
		.shouldEnableSwipes(draggableHandler.orientation)
		}

		var isIntercepting = false

		return PriorityNestedScrollConnection(
		orientation = draggableHandler.orientation,
		canStartPreScroll = { offsetAvailable, offsetBeforeStart, _ ->
		val pointersDown: PointersInfo.PointersDown? =
		when (val info = pointersInfoOwner.pointersInfo()) {
		PointersInfo.MouseWheel -> {
		// Do not support mouse wheel interactions
		return@PriorityNestedScrollConnection false
		}

		is PointersInfo.PointersDown -> info
		null -> null
		}

		canChangeScene =
		if (isExternalOverscrollGesture()) false else offsetBeforeStart == 0f

		val canInterceptSwipeTransition =
		canChangeScene &&
		offsetAvailable != 0f &&
		draggableHandler.shouldImmediatelyIntercept(pointersDown)
		if (!canInterceptSwipeTransition) return@PriorityNestedScrollConnection false

		val layoutImpl = draggableHandler.layoutImpl
		val threshold = layoutImpl.transitionInterceptionThreshold
		val hasSnappedToIdle = layoutImpl.state.snapToIdleIfClose(threshold)
		if (hasSnappedToIdle) {
		// If the current swipe transition is closed to 0f or 1f, then we want to
		// interrupt the transition (snapping it to Idle) and scroll the list.
		return@PriorityNestedScrollConnection false
		}

		lastPointersDown = pointersDown

		// If the current swipe transition is not closed to 0f or 1f, then we want the
		// scroll events to intercept the current transition to continue the scene
		// transition.
		isIntercepting = true
		true
		},
		canStartPreScroll = { _, _, _ -> false },
		canStartPostScroll = { offsetAvailable, offsetBeforeStart, _ ->
		val behavior: NestedScrollBehavior =
		when {
		@@ -629,7 +486,6 @@ internal class NestedScrollHandlerImpl(
		}
		lastPointersDown = pointersDown

		val canStart =
		when (behavior) {
		NestedScrollBehavior.EdgeNoPreview -> {
		canChangeScene = isZeroOffset
		@@ -646,12 +502,6 @@ internal class NestedScrollHandlerImpl(
		shouldEnableSwipes()
		}
		}

		if (canStart) {
		isIntercepting = false
		}

		canStart
		},
		canStartPostFling = { velocityAvailable ->
		val behavior: NestedScrollBehavior =
		@@ -676,19 +526,14 @@ internal class NestedScrollHandlerImpl(
		}
		lastPointersDown = pointersDown

		val canStart = behavior.canStartOnPostFling && shouldEnableSwipes()
		if (canStart) {
		isIntercepting = false
		}

		canStart
		behavior.canStartOnPostFling && shouldEnableSwipes()
		},
		onStart = { firstScroll ->
		scrollController(
		dragController =
		draggableHandler.onDragStarted(
		pointersDown = lastPointersDown,
		overSlop = if (isIntercepting) 0f else firstScroll,
		overSlop = firstScroll,
		),
		canChangeScene = canChangeScene,
		pointersInfoOwner = pointersInfoOwner,

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

+37 −68

Original line number	Diff line number	Diff line
		@@ -80,7 +80,6 @@ import kotlinx.coroutines.launch
		@Stable
		internal fun Modifier.multiPointerDraggable(
		orientation: Orientation,
		startDragImmediately: (pointersDown: PointersInfo.PointersDown) -> Boolean,
		onDragStarted: (pointersDown: PointersInfo.PointersDown, overSlop: Float) -> DragController,
		onFirstPointerDown: () -> Unit = {},
		swipeDetector: SwipeDetector = DefaultSwipeDetector,
		@@ -89,7 +88,6 @@ internal fun Modifier.multiPointerDraggable(
		this.then(
		MultiPointerDraggableElement(
		orientation,
		startDragImmediately,
		onDragStarted,
		onFirstPointerDown,
		swipeDetector,
		@@ -99,7 +97,6 @@ internal fun Modifier.multiPointerDraggable(

		private data class MultiPointerDraggableElement(
		private val orientation: Orientation,
		private val startDragImmediately: (pointersDown: PointersInfo.PointersDown) -> Boolean,
		private val onDragStarted:
		(pointersDown: PointersInfo.PointersDown, overSlop: Float) -> DragController,
		private val onFirstPointerDown: () -> Unit,
		@@ -109,7 +106,6 @@ private data class MultiPointerDraggableElement(
		override fun create(): MultiPointerDraggableNode =
		MultiPointerDraggableNode(
		orientation = orientation,
		startDragImmediately = startDragImmediately,
		onDragStarted = onDragStarted,
		onFirstPointerDown = onFirstPointerDown,
		swipeDetector = swipeDetector,
		@@ -118,7 +114,6 @@ private data class MultiPointerDraggableElement(

		override fun update(node: MultiPointerDraggableNode) {
		node.orientation = orientation
		node.startDragImmediately = startDragImmediately
		node.onDragStarted = onDragStarted
		node.onFirstPointerDown = onFirstPointerDown
		node.swipeDetector = swipeDetector
		@@ -127,7 +122,6 @@ private data class MultiPointerDraggableElement(

		internal class MultiPointerDraggableNode(
		orientation: Orientation,
		var startDragImmediately: (pointersDown: PointersInfo.PointersDown) -> Boolean,
		var onDragStarted: (pointersDown: PointersInfo.PointersDown, overSlop: Float) -> DragController,
		var onFirstPointerDown: () -> Unit,
		swipeDetector: SwipeDetector = DefaultSwipeDetector,
		@@ -297,7 +291,6 @@ internal class MultiPointerDraggableNode(
		try {
		detectDragGestures(
		orientation = orientation,
		startDragImmediately = startDragImmediately,
		onDragStart = { pointersDown, overSlop ->
		onDragStarted(pointersDown, overSlop)
		},
		@@ -438,13 +431,11 @@ internal class MultiPointerDraggableNode(
		* Detect drag gestures in the given [orientation].
		*
		* This function is a mix of [androidx.compose.foundation.gestures.awaitDownAndSlop] and
		* [androidx.compose.foundation.gestures.detectVerticalDragGestures] to add support for:
		* 1) starting the gesture immediately without requiring a drag >= touch slope;
		* 2) passing the number of pointers down to [onDragStart].
		* [androidx.compose.foundation.gestures.detectVerticalDragGestures] to add support for passing
		* the number of pointers down to [onDragStart].
		*/
		private suspend fun AwaitPointerEventScope.detectDragGestures(
		orientation: Orientation,
		startDragImmediately: (pointersDown: PointersInfo.PointersDown) -> Boolean,
		onDragStart: (pointersDown: PointersInfo.PointersDown, overSlop: Float) -> DragController,
		onDrag: (controller: DragController, dragAmount: Float) -> Unit,
		onDragEnd: (controller: DragController) -> Unit,
		@@ -470,17 +461,6 @@ internal class MultiPointerDraggableNode(
		.first()

		var overSlop = 0f
		var lastPointersDown: PointersInfo.PointersDown =
		checkNotNull(pointersInfo()) {
		"We should have pointers down, last event: $currentEvent"
		}
		as PointersInfo.PointersDown

		val drag =
		if (startDragImmediately(lastPointersDown)) {
		consumablePointer.consume()
		consumablePointer
		} else {
		val onSlopReached = { change: PointerInputChange, over: Float ->
		if (swipeDetector.detectSwipe(change)) {
		change.consume()
		@@ -493,27 +473,19 @@ internal class MultiPointerDraggableNode(
		val drag =
		when (orientation) {
		Orientation.Horizontal ->
		awaitHorizontalTouchSlopOrCancellation(
		consumablePointer.id,
		onSlopReached,
		)
		awaitHorizontalTouchSlopOrCancellation(consumablePointer.id, onSlopReached)
		Orientation.Vertical ->
		awaitVerticalTouchSlopOrCancellation(
		consumablePointer.id,
		onSlopReached,
		)
		awaitVerticalTouchSlopOrCancellation(consumablePointer.id, onSlopReached)
		} ?: return

		lastPointersDown =
		val lastPointersDown =
		checkNotNull(pointersInfo()) {
		"We should have pointers down, last event: $currentEvent"
		}
		as PointersInfo.PointersDown
		// Make sure that overSlop is not 0f. This can happen when the user drags by exactly
		// the touch slop. However, the overSlop we pass to onDragStarted() is used to
		// compute the direction we are dragging in, so overSlop should never be 0f unless
		// we intercept an ongoing swipe transition (i.e. startDragImmediately() returned
		// true).
		// compute the direction we are dragging in, so overSlop should never be 0f.
		if (overSlop == 0f) {
		// If the user drags in the opposite direction, the delta becomes zero because
		// we return to the original point. Therefore, we should use the previous event
		@@ -530,11 +502,8 @@ internal class MultiPointerDraggableNode(
		}
		overSlop = delta.sign
		}
		drag
		}

		val controller = onDragStart(lastPointersDown, overSlop)

		val successful: Boolean
		try {
		onDrag(controller, overSlop)

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

+0 −16

Original line number	Diff line number	Diff line
		@@ -149,7 +149,6 @@ private class SwipeToSceneNode(
		delegate(
		MultiPointerDraggableNode(
		orientation = draggableHandler.orientation,
		startDragImmediately = ::startDragImmediately,
		onDragStarted = draggableHandler::onDragStarted,
		onFirstPointerDown = ::onFirstPointerDown,
		swipeDetector = swipeDetector,
		@@ -198,21 +197,6 @@ private class SwipeToSceneNode(
		) = multiPointerDraggableNode.onPointerEvent(pointerEvent, pass, bounds)

		override fun onCancelPointerInput() = multiPointerDraggableNode.onCancelPointerInput()

		private fun startDragImmediately(pointersDown: PointersInfo.PointersDown): Boolean {
		// Immediately start the drag if the user can't swipe in the other direction and the gesture
		// handler can intercept it.
		return !canOppositeSwipe() && draggableHandler.shouldImmediatelyIntercept(pointersDown)
		}

		private fun canOppositeSwipe(): Boolean {
		val oppositeOrientation =
		when (draggableHandler.orientation) {
		Orientation.Vertical -> Orientation.Horizontal
		Orientation.Horizontal -> Orientation.Vertical
		}
		return draggableHandler.contentForSwipes().shouldEnableSwipes(oppositeOrientation)
		}
		}

		/** Find the [ScrollBehaviorOwner] for the current orientation. */

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

+6 −242

File changed.

Preview size limit exceeded, changes collapsed.

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

+0 −11

Original line number	Diff line number	Diff line
		@@ -101,7 +101,6 @@ class MultiPointerDraggableTest {
		.thenIf(enabled) {
		Modifier.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		onDragStarted = { _, _ ->
		started = true
		SimpleDragController(
		@@ -169,8 +168,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		// We want to start a drag gesture immediately
		startDragImmediately = { true },
		onDragStarted = { _, _ ->
		started = true
		SimpleDragController(
		@@ -242,7 +239,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		onDragStarted = { _, _ ->
		started = true
		SimpleDragController(
		@@ -361,7 +357,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		onDragStarted = { _, _ ->
		started = true
		SimpleDragController(
		@@ -466,7 +461,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		onDragStarted = { _, _ ->
		verticalStarted = true
		SimpleDragController(
		@@ -478,7 +472,6 @@ class MultiPointerDraggableTest {
		)
		.multiPointerDraggable(
		orientation = Orientation.Horizontal,
		startDragImmediately = { false },
		onDragStarted = { _, _ ->
		horizontalStarted = true
		SimpleDragController(
		@@ -570,7 +563,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		swipeDetector =
		object : SwipeDetector {
		override fun detectSwipe(change: PointerInputChange): Boolean {
		@@ -636,7 +628,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		swipeDetector =
		object : SwipeDetector {
		override fun detectSwipe(change: PointerInputChange): Boolean {
		@@ -738,7 +729,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		onDragStarted = { _, _ ->
		SimpleDragController(
		onDrag = { consumedOnDrag = it },
		@@ -809,7 +799,6 @@ class MultiPointerDraggableTest {
		.nestedScrollDispatcher()
		.multiPointerDraggable(
		orientation = Orientation.Vertical,
		startDragImmediately = { false },
		onDragStarted = { _, _ ->
		SimpleDragController(
		onDrag = { /* do nothing */ },