Enforce that onDragStarted.overSlop is != 0f
This CL ensures that the overSlop passed to
SceneGestureHandler.onDragStarter() is different than 0f if we are not
interrupting the current transition.
Bug: 291053278
Test: PlatformComposeSceneTransitionLayoutTests
Flag: N/A
Change-Id: I3300b3b2ceb51a90a15c11d9f67c9b5c10fcbb06
diff --git a/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/SceneGestureHandler.kt b/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/SceneGestureHandler.kt
index 333eef7..36e290f 100644
--- a/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/SceneGestureHandler.kt
+++ b/packages/SystemUI/compose/scene/src/com/android/compose/animation/scene/SceneGestureHandler.kt
@@ -96,6 +96,9 @@
return
}
+ check(overSlop != 0f) {
+ "onDragStarted() called while isDrivingTransition=false overSlop=0f"
+ }
val transitionState = layoutState.transitionState
if (transitionState is TransitionState.Transition) {
// TODO(b/290184746): Better handle interruptions here if state != idle.
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 2841bcf..ac11d30 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
@@ -22,6 +22,7 @@
import androidx.compose.ui.input.nestedscroll.NestedScrollSource
import androidx.compose.ui.unit.Velocity
import com.android.compose.ui.util.SpaceVectorConverter
+import kotlin.math.sign
/**
* This [NestedScrollConnection] waits for a child to scroll ([onPreScroll] or [onPostScroll]), and
@@ -117,7 +118,12 @@
return Velocity.Zero
}
- onPriorityStart(available = Offset.Zero)
+ // The offset passed to onPriorityStart() must be != 0f, so we create a small offset of 1px
+ // given the available velocity.
+ // TODO(b/291053278): Remove canStartPostFling() and instead make it possible to define the
+ // overscroll behavior on the Scene level.
+ val smallOffset = Offset(available.x.sign, available.y.sign)
+ onPriorityStart(available = smallOffset)
// This is the last event of a scroll gesture.
return onPriorityStop(available)
diff --git a/packages/SystemUI/compose/scene/tests/src/com/android/compose/animation/scene/SceneGestureHandlerTest.kt b/packages/SystemUI/compose/scene/tests/src/com/android/compose/animation/scene/SceneGestureHandlerTest.kt
index 4b3b369..88363ad 100644
--- a/packages/SystemUI/compose/scene/tests/src/com/android/compose/animation/scene/SceneGestureHandlerTest.kt
+++ b/packages/SystemUI/compose/scene/tests/src/com/android/compose/animation/scene/SceneGestureHandlerTest.kt
@@ -192,16 +192,14 @@
@Test
fun onDragStarted_shouldStartATransition() = runGestureTest {
- draggable.onDragStarted()
+ draggable.onDragStarted(overSlop = down(0.1f))
assertTransition(currentScene = SceneA)
}
@Test
fun afterSceneTransitionIsStarted_interceptDragEvents() = runGestureTest {
- draggable.onDragStarted()
+ draggable.onDragStarted(overSlop = down(0.1f))
assertTransition(currentScene = SceneA)
-
- draggable.onDelta(pixels = down(0.1f))
assertThat(progress).isEqualTo(0.1f)
draggable.onDelta(pixels = down(0.1f))
@@ -210,10 +208,7 @@
@Test
fun onDragStoppedAfterDrag_velocityLowerThanThreshold_remainSameScene() = runGestureTest {
- draggable.onDragStarted()
- assertTransition(currentScene = SceneA)
-
- draggable.onDelta(pixels = down(0.1f))
+ draggable.onDragStarted(overSlop = down(0.1f))
assertTransition(currentScene = SceneA)
draggable.onDragStopped(
@@ -228,10 +223,7 @@
@Test
fun onDragStoppedAfterDrag_velocityAtLeastThreshold_goToNextScene() = runGestureTest {
- draggable.onDragStarted()
- assertTransition(currentScene = SceneA)
-
- draggable.onDelta(pixels = down(0.1f))
+ draggable.onDragStarted(overSlop = down(0.1f))
assertTransition(currentScene = SceneA)
draggable.onDragStopped(velocity = velocityThreshold)
@@ -245,7 +237,7 @@
@Test
fun onDragStoppedAfterStarted_returnToIdle() = runGestureTest {
- draggable.onDragStarted()
+ draggable.onDragStarted(overSlop = down(0.1f))
assertTransition(currentScene = SceneA)
draggable.onDragStopped(velocity = 0f)
@@ -256,8 +248,7 @@
@Test
fun onDragReversedDirection_changeToScene() = runGestureTest {
// Drag A -> B with progress 0.6
- draggable.onDragStarted()
- draggable.onDelta(up(0.6f))
+ draggable.onDragStarted(overSlop = up(0.6f))
assertTransition(
currentScene = SceneA,
fromScene = SceneA,
@@ -366,8 +357,7 @@
@Test
fun onAccelaratedScroll_scrollToThirdScene() = runGestureTest {
// Drag A -> B with progress 0.2
- draggable.onDragStarted()
- draggable.onDelta(up(0.2f))
+ draggable.onDragStarted(overSlop = up(0.2f))
assertTransition(
currentScene = SceneA,
fromScene = SceneA,
@@ -401,9 +391,7 @@
@Test
fun onAccelaratedScrollBothTargetsBecomeNull_settlesToIdle() = runGestureTest {
- draggable.onDragStarted()
- draggable.onDelta(up(0.2f))
-
+ draggable.onDragStarted(overSlop = up(0.2f))
draggable.onDelta(up(0.2f))
draggable.onDragStopped(velocity = -velocityThreshold)
assertTransition(currentScene = SceneB, fromScene = SceneA, toScene = SceneB)
@@ -459,16 +447,14 @@
draggable.onDragStopped(down(0.1f))
// now target changed to C for new drag that started before previous drag settled to Idle
- draggable.onDragStarted(up(0.1f))
+ draggable.onDragStarted(overSlop = 0f)
+ draggable.onDelta(up(0.1f))
assertTransition(fromScene = SceneA, toScene = SceneC, progress = 0.3f)
}
@Test
fun startGestureDuringAnimatingOffset_shouldImmediatelyStopTheAnimation() = runGestureTest {
- draggable.onDragStarted()
- assertTransition(currentScene = SceneA)
-
- draggable.onDelta(pixels = down(0.1f))
+ draggable.onDragStarted(overSlop = down(0.1f))
assertTransition(currentScene = SceneA)
draggable.onDragStopped(
@@ -759,10 +745,8 @@
@Test
fun startNestedScrollWhileDragging() = runGestureTest {
val nestedScroll = nestedScrollConnection(nestedScrollBehavior = EdgeAlways)
- draggable.onDragStarted()
+ draggable.onDragStarted(overSlop = down(0.1f))
assertTransition(currentScene = SceneA)
-
- draggable.onDelta(down(0.1f))
assertThat(progress).isEqualTo(0.1f)
// now we can intercept the scroll events