STL remove PriorityNestedScrollConnection.canStartPostFling

This will be converted to an OverscrollEffect in a later CL.

For more information, see b/378470603

Test: Removed canStartPostFling tests.
Test: Manually tested on Flexiglass.
Bug: 378470603
Flag: com.android.systemui.scene_container
Change-Id: Ib99a12e28a3b5441a55a823ac3c7bee04139a1a8

7 files changed, 31 insertions, 84 deletions

diff --git a/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationScrimNestedScrollConnection.kt b/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationScrimNestedScrollConnection.kt
index 94c18cdbef5a..cb87f0e7cf1c 100644
--- a/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationScrimNestedScrollConnection.kt
+++ b/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationScrimNestedScrollConnection.kt
@@ -62,7 +62,6 @@ fun NotificationScrimNestedScrollConnection(
         canStartPostScroll = { offsetAvailable, _, _ ->
             offsetAvailable > 0 && (scrimOffset() < maxScrimOffset || isCurrentGestureOverscroll())
         },
-        canStartPostFling = { false },
         onStart = { firstScroll ->
             onStart(firstScroll)
             object : ScrollController {
diff --git a/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationStackNestedScrollConnection.kt b/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationStackNestedScrollConnection.kt
index d8abfd7a4b94..e1ee59ba0626 100644
--- a/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationStackNestedScrollConnection.kt
+++ b/packages/SystemUI/compose/features/src/com/android/systemui/notifications/ui/composable/NotificationStackNestedScrollConnection.kt
@@ -25,11 +25,13 @@ import androidx.compose.foundation.layout.offset
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.remember
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.input.nestedscroll.NestedScrollConnection
 import androidx.compose.ui.input.nestedscroll.NestedScrollSource
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.platform.LocalConfiguration
 import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.unit.IntOffset
+import androidx.compose.ui.unit.Velocity
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.util.fastCoerceAtLeast
 import com.android.compose.nestedscroll.OnStopScope
@@ -80,9 +82,29 @@ fun Modifier.stackVerticalOverscroll(
         }
 
     return this.then(
-        Modifier.nestedScroll(stackNestedScrollConnection).offset {
-            IntOffset(x = 0, y = overscrollOffset.value.roundToInt())
-        }
+        Modifier.nestedScroll(
+                remember {
+                    object : NestedScrollConnection {
+                        override suspend fun onPostFling(
+                            consumed: Velocity,
+                            available: Velocity,
+                        ): Velocity {
+                            return if (available.y < 0f && !canScrollForward()) {
+                                overscrollOffset.animateTo(
+                                    targetValue = 0f,
+                                    initialVelocity = available.y,
+                                    animationSpec = tween(),
+                                )
+                                available
+                            } else {
+                                Velocity.Zero
+                            }
+                        }
+                    }
+                }
+            )
+            .nestedScroll(stackNestedScrollConnection)
+            .offset { IntOffset(x = 0, y = overscrollOffset.value.roundToInt()) }
     )
 }
 
@@ -100,7 +122,6 @@ fun NotificationStackNestedScrollConnection(
         canStartPostScroll = { offsetAvailable, offsetBeforeStart, _ ->
             offsetAvailable < 0f && offsetBeforeStart < 0f && !canScrollForward()
         },
-        canStartPostFling = { velocityAvailable -> velocityAvailable < 0f && !canScrollForward() },
         onStart = { firstScroll ->
             onStart(firstScroll)
             object : ScrollController {
diff --git a/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/DraggableHandler.kt b/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/DraggableHandler.kt
index 2d589f37f3cb..737a89630a8f 100644
--- a/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/DraggableHandler.kt
+++ b/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/DraggableHandler.kt
@@ -536,31 +536,6 @@ internal class NestedScrollHandlerImpl(
                     }
                 }
             },
-            canStartPostFling = { velocityAvailable ->
-                val behavior: NestedScrollBehavior =
-                    when {
-                        velocityAvailable > 0f -> topOrLeftBehavior
-                        velocityAvailable < 0f -> bottomOrRightBehavior
-                        else -> return@PriorityNestedScrollConnection false
-                    }
-
-                // We could start an overscroll animation
-                canChangeScene = false
-
-                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
-                    }
-                lastPointersDown = pointersDown
-
-                behavior.canStartOnPostFling && shouldEnableSwipes()
-            },
             onStart = { firstScroll ->
                 scrollController(
                     dragController =
diff --git a/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/NestedScrollToScene.kt b/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/NestedScrollToScene.kt
index 955be603efaf..9622fc151bb7 100644
--- a/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/NestedScrollToScene.kt
+++ b/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/NestedScrollToScene.kt
@@ -32,7 +32,7 @@ import androidx.compose.ui.platform.InspectorInfo
  * not consumed by the [SceneTransitionLayout] unless specifically requested via
  * [nestedScrollToScene].
  */
-enum class NestedScrollBehavior(val canStartOnPostFling: Boolean) {
+enum class NestedScrollBehavior {
     /**
      * Overscroll will only be used by the [SceneTransitionLayout] to move to the next scene if the
      * gesture begins at the edge of the scrollable component (so that a scroll in that direction
@@ -42,7 +42,7 @@ enum class NestedScrollBehavior(val canStartOnPostFling: Boolean) {
      * In addition, during scene transitions, scroll events are consumed by the
      * [SceneTransitionLayout] instead of the scrollable component.
      */
-    EdgeNoPreview(canStartOnPostFling = false),
+    EdgeNoPreview,
 
     /**
      * Overscroll will only be used by the [SceneTransitionLayout] to move to the next scene if the
@@ -52,7 +52,7 @@ enum class NestedScrollBehavior(val canStartOnPostFling: Boolean) {
      * In addition, during scene transitions, scroll events are consumed by the
      * [SceneTransitionLayout] instead of the scrollable component.
      */
-    EdgeWithPreview(canStartOnPostFling = true),
+    @Deprecated("This will be removed, see b/378470603") EdgeWithPreview,
 
     /**
      * Any overscroll will be used by the [SceneTransitionLayout] to move to the next scene.
@@ -60,7 +60,7 @@ enum class NestedScrollBehavior(val canStartOnPostFling: Boolean) {
      * In addition, during scene transitions, scroll events are consumed by the
      * [SceneTransitionLayout] instead of the scrollable component.
      */
-    EdgeAlways(canStartOnPostFling = true);
+    EdgeAlways;
 
     companion object {
         val Default = EdgeNoPreview
diff --git a/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/LargeTopAppBarNestedScrollConnection.kt b/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/LargeTopAppBarNestedScrollConnection.kt
index 98a00173f1d7..b26bf55c85ec 100644
--- a/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/LargeTopAppBarNestedScrollConnection.kt
+++ b/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/LargeTopAppBarNestedScrollConnection.kt
@@ -56,7 +56,6 @@ fun LargeTopAppBarNestedScrollConnection(
         canStartPostScroll = { offsetAvailable, _, _ ->
             offsetAvailable > 0 && height() < maxHeight()
         },
-        canStartPostFling = { false },
         onStart = {
             LargeTopAppBarScrollController(
                 height = height,
diff --git a/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/PriorityNestedScrollConnection.kt b/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/PriorityNestedScrollConnection.kt
index 3f182363e20c..3d0f182fffee 100644
--- a/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/PriorityNestedScrollConnection.kt
+++ b/packages/SystemUI/compose/scene/src/com/android/compose/nestedscroll/PriorityNestedScrollConnection.kt
@@ -24,7 +24,6 @@ import androidx.compose.ui.input.nestedscroll.NestedScrollConnection
 import androidx.compose.ui.input.nestedscroll.NestedScrollSource
 import androidx.compose.ui.unit.Velocity
 import com.android.compose.ui.util.SpaceVectorConverter
-import kotlin.math.sign
 import kotlinx.coroutines.Deferred
 import kotlinx.coroutines.async
 import kotlinx.coroutines.coroutineScope
@@ -102,8 +101,8 @@ interface OnStopScope {
  * over the default nested scrolling logic.
  *
  * When started, this connection intercepts scroll events *before* they reach child composables.
- * This "priority mode" is activated activated when either [canStartPreScroll], [canStartPostScroll]
- * or [canStartPostFling] returns `true`.
+ * This "priority mode" is activated when either [canStartPreScroll] or [canStartPostScroll] returns
+ * `true`.
  *
  * Once started, the [onStart] lambda provides a [ScrollController] to manage the scrolling. This
  * controller allows you to directly manipulate the scroll state and define how scroll events are
@@ -123,8 +122,6 @@ interface OnStopScope {
  * @param canStartPostScroll A lambda that returns `true` if the connection should enter priority
  *   mode during the post-scroll phase. This is called after child connections have consumed the
  *   scroll.
- * @param canStartPostFling A lambda that returns `true` if the connection should enter priority
- *   mode during the post-fling phase. This is called after a fling gesture has been initiated.
  * @param onStart A lambda that is called when the connection enters priority mode. It should return
  *   a [ScrollController] that will be used to control the scroll.
  * @sample LargeTopAppBarNestedScrollConnection
@@ -136,7 +133,6 @@ class PriorityNestedScrollConnection(
         (offsetAvailable: Float, offsetBeforeStart: Float, source: NestedScrollSource) -> Boolean,
     private val canStartPostScroll:
         (offsetAvailable: Float, offsetBeforeStart: Float, source: NestedScrollSource) -> Boolean,
-    private val canStartPostFling: (velocityAvailable: Float) -> Boolean,
     private val onStart: (firstScroll: Float) -> ScrollController,
 ) : NestedScrollConnection, SpaceVectorConverter by SpaceVectorConverter(orientation) {
 
@@ -233,17 +229,6 @@ class PriorityNestedScrollConnection(
             return stop(velocity = availableFloat)
         }
 
-        // Check if post-fling condition is met, and start priority mode if necessary.
-        // TODO(b/291053278): Remove canStartPostFling() and instead make it possible to define the
-        // overscroll behavior on the Scene level.
-        if (canStartPostFling(availableFloat)) {
-            // The offset passed to onPriorityStart() must be != 0f, so we create a small offset of
-            // 1px given the available velocity.
-            val smallOffset = availableFloat.sign
-            start(availableOffset = smallOffset)
-            return stop(availableFloat)
-        }
-
         // Reset offset tracking after the fling gesture is finished.
         resetOffsetTracker()
         return Velocity.Zero
diff --git a/packages/SystemUI/compose/scene/tests/src/com/android/compose/nestedscroll/PriorityNestedScrollConnectionTest.kt b/packages/SystemUI/compose/scene/tests/src/com/android/compose/nestedscroll/PriorityNestedScrollConnectionTest.kt
index 28ea2d239b54..51483a894e1e 100644
--- a/packages/SystemUI/compose/scene/tests/src/com/android/compose/nestedscroll/PriorityNestedScrollConnectionTest.kt
+++ b/packages/SystemUI/compose/scene/tests/src/com/android/compose/nestedscroll/PriorityNestedScrollConnectionTest.kt
@@ -39,7 +39,6 @@ import org.junit.runner.RunWith
 class PriorityNestedScrollConnectionTest {
     private var canStartPreScroll = false
     private var canStartPostScroll = false
-    private var canStartPostFling = false
     private var canStopOnPreFling = true
     private var isStarted = false
     private var lastScroll: Float? = null
@@ -63,7 +62,6 @@ class PriorityNestedScrollConnectionTest {
             orientation = Orientation.Vertical,
             canStartPreScroll = { _, _, _ -> canStartPreScroll },
             canStartPostScroll = { _, _, _ -> canStartPostScroll },
-            canStartPostFling = { canStartPostFling },
             onStart = { _ ->
                 isStarted = true
                 object : ScrollController {
@@ -239,36 +237,6 @@ class PriorityNestedScrollConnectionTest {
     }
 
     @Test
-    fun receive_onPostFling() = runTest {
-        canStartPostFling = true
-
-        scrollConnection.onPostFling(consumed = Velocity(1f, 1f), available = Velocity(2f, 2f))
-
-        assertThat(lastStop).isEqualTo(2f)
-    }
-
-    @Test
-    fun step1_priorityModeShouldStartOnlyOnPostFling() = runTest {
-        canStartPostFling = true
-
-        scrollConnection.onPreScroll(available = Offset.Zero, source = UserInput)
-        assertThat(isStarted).isEqualTo(false)
-
-        scrollConnection.onPostScroll(
-            consumed = Offset.Zero,
-            available = Offset.Zero,
-            source = UserInput,
-        )
-        assertThat(isStarted).isEqualTo(false)
-
-        scrollConnection.onPreFling(available = Velocity.Zero)
-        assertThat(isStarted).isEqualTo(false)
-
-        scrollConnection.onPostFling(consumed = Velocity.Zero, available = Velocity.Zero)
-        assertThat(isStarted).isEqualTo(true)
-    }
-
-    @Test
     fun handleMultipleOnPreFlingCalls() = runTest {
         startPriorityModePostScroll()