5 files changed, 191 insertions, 4 deletions
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt
index e3666ce66d5c..084da2c59776 100644
--- a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/BackGestureMonitor.kt
@@ -23,7 +23,7 @@ class BackGestureMonitor(
     override val gestureDistanceThresholdPx: Int,
     override val gestureStateChangedCallback: (GestureState) -> Unit
 ) :
-    TouchpadGestureMonitor by ThreeFingerGestureMonitor(
+    TouchpadGestureMonitor by ThreeFingerDistanceBasedGestureMonitor(
         gestureDistanceThresholdPx = gestureDistanceThresholdPx,
         gestureStateChangedCallback = gestureStateChangedCallback,
         donePredicate =
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/HomeGestureMonitor.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/HomeGestureMonitor.kt
index a410f991182e..a9aa5c897573 100644
--- a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/HomeGestureMonitor.kt
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/HomeGestureMonitor.kt
@@ -21,7 +21,7 @@ class HomeGestureMonitor(
     override val gestureDistanceThresholdPx: Int,
     override val gestureStateChangedCallback: (GestureState) -> Unit
 ) :
-    TouchpadGestureMonitor by ThreeFingerGestureMonitor(
+    TouchpadGestureMonitor by ThreeFingerDistanceBasedGestureMonitor(
         gestureDistanceThresholdPx = gestureDistanceThresholdPx,
         gestureStateChangedCallback = gestureStateChangedCallback,
         donePredicate =
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/RecentAppsGestureMonitor.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/RecentAppsGestureMonitor.kt
new file mode 100644
index 000000000000..58282393d4a6
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/RecentAppsGestureMonitor.kt
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+import android.view.MotionEvent
+import androidx.compose.ui.input.pointer.util.VelocityTracker1D
+import kotlin.math.abs
+
+/**
+ * Monitors recent apps gesture completion. That is - using three fingers on touchpad - swipe up
+ * over some distance threshold and then slow down gesture before fingers are lifted. Implementation
+ * is based on [com.android.quickstep.util.TriggerSwipeUpTouchTracker]
+ */
+class RecentAppsGestureMonitor(
+    override val gestureDistanceThresholdPx: Int,
+    override val gestureStateChangedCallback: (GestureState) -> Unit,
+    private val velocityThresholdPxPerMs: Float,
+    private val velocityTracker: VelocityTracker1D = VelocityTracker1D(isDataDifferential = false),
+) : TouchpadGestureMonitor {
+
+    private var xStart = 0f
+    private var yStart = 0f
+
+    override fun processTouchpadEvent(event: MotionEvent) {
+        val action = event.actionMasked
+        velocityTracker.addDataPoint(event.eventTime, event.y)
+        when (action) {
+            MotionEvent.ACTION_DOWN -> {
+                if (isThreeFingerTouchpadSwipe(event)) {
+                    xStart = event.x
+                    yStart = event.y
+                    gestureStateChangedCallback(GestureState.IN_PROGRESS)
+                }
+            }
+            MotionEvent.ACTION_UP -> {
+                if (isThreeFingerTouchpadSwipe(event) && isRecentAppsGesture(event)) {
+                    gestureStateChangedCallback(GestureState.FINISHED)
+                } else {
+                    gestureStateChangedCallback(GestureState.NOT_STARTED)
+                }
+                velocityTracker.resetTracking()
+            }
+            MotionEvent.ACTION_CANCEL -> {
+                velocityTracker.resetTracking()
+            }
+        }
+    }
+
+    private fun isRecentAppsGesture(event: MotionEvent): Boolean {
+        // below is trying to mirror behavior of TriggerSwipeUpTouchTracker#onGestureEnd.
+        // We're diving velocity by 1000, to have the same unit of measure: pixels/ms.
+        val swipeDistance = yStart - event.y
+        val velocity = velocityTracker.calculateVelocity() / 1000
+        return swipeDistance >= gestureDistanceThresholdPx &&
+            abs(velocity) <= velocityThresholdPxPerMs
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/ThreeFingerGestureMonitor.kt b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/ThreeFingerDistanceBasedGestureMonitor.kt
index 377977ce0d74..9bf0fe96624f 100644
--- a/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/ThreeFingerGestureMonitor.kt
+++ b/packages/SystemUI/src/com/android/systemui/touchpad/tutorial/ui/gesture/ThreeFingerDistanceBasedGestureMonitor.kt
@@ -25,8 +25,12 @@ interface GestureDonePredicate {
     fun wasGestureDone(startX: Float, startY: Float, endX: Float, endY: Float): Boolean
 }
 
-/** Common implementation for all three-finger gesture monitors */
-class ThreeFingerGestureMonitor(
+/**
+ * Common implementation for three-finger gesture monitors that are only distance-based. E.g. recent
+ * apps gesture is not only distance-based because it requires going over threshold distance and
+ * slowing down the movement.
+ */
+class ThreeFingerDistanceBasedGestureMonitor(
     override val gestureDistanceThresholdPx: Int,
     override val gestureStateChangedCallback: (GestureState) -> Unit,
     private val donePredicate: GestureDonePredicate
diff --git a/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/RecentAppsGestureMonitorTest.kt b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/RecentAppsGestureMonitorTest.kt
new file mode 100644
index 000000000000..cafebb9fd79e
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/touchpad/tutorial/ui/gesture/RecentAppsGestureMonitorTest.kt
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.touchpad.tutorial.ui.gesture
+
+import android.view.MotionEvent
+import androidx.compose.ui.input.pointer.util.VelocityTracker1D
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.touchpad.tutorial.ui.gesture.GestureState.FINISHED
+import com.android.systemui.touchpad.tutorial.ui.gesture.GestureState.IN_PROGRESS
+import com.android.systemui.touchpad.tutorial.ui.gesture.GestureState.NOT_STARTED
+import com.android.systemui.touchpad.tutorial.ui.gesture.MultiFingerGesture.Companion.SWIPE_DISTANCE
+import com.google.common.truth.Truth.assertThat
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.kotlin.doReturn
+import org.mockito.kotlin.mock
+import org.mockito.kotlin.whenever
+
+@SmallTest
+@RunWith(AndroidJUnit4::class)
+class RecentAppsGestureMonitorTest : SysuiTestCase() {
+
+    companion object {
+        const val THRESHOLD_VELOCITY_PX_PER_MS = 0.1f
+        // multiply by 1000 to get px per ms instead of px per s which is unit used by velocity
+        // tracker
+        const val SLOW = THRESHOLD_VELOCITY_PX_PER_MS * 1000 - 1
+        const val FAST = THRESHOLD_VELOCITY_PX_PER_MS * 1000 + 1
+    }
+
+    private var gestureState = NOT_STARTED
+    private val velocityTracker =
+        mock<VelocityTracker1D> {
+            // by default return correct speed for the gesture - as if pointer is slowing down
+            on { calculateVelocity() } doReturn SLOW
+        }
+    private val gestureMonitor =
+        RecentAppsGestureMonitor(
+            gestureDistanceThresholdPx = SWIPE_DISTANCE.toInt(),
+            gestureStateChangedCallback = { gestureState = it },
+            velocityThresholdPxPerMs = THRESHOLD_VELOCITY_PX_PER_MS,
+            velocityTracker = velocityTracker
+        )
+
+    @Test
+    fun triggersGestureFinishedForThreeFingerGestureUp() {
+        assertStateAfterEvents(events = ThreeFingerGesture.swipeUp(), expectedState = FINISHED)
+    }
+
+    @Test
+    fun doesntTriggerGestureFinished_onGestureSpeedTooHigh() {
+        whenever(velocityTracker.calculateVelocity()).thenReturn(FAST)
+        assertStateAfterEvents(events = ThreeFingerGesture.swipeUp(), expectedState = NOT_STARTED)
+    }
+
+    @Test
+    fun triggersGestureProgressForThreeFingerGestureStarted() {
+        assertStateAfterEvents(
+            events = ThreeFingerGesture.startEvents(x = 0f, y = 0f),
+            expectedState = IN_PROGRESS
+        )
+    }
+
+    @Test
+    fun doesntTriggerGestureFinished_onGestureDistanceTooShort() {
+        assertStateAfterEvents(
+            events = ThreeFingerGesture.swipeUp(distancePx = SWIPE_DISTANCE / 2),
+            expectedState = NOT_STARTED
+        )
+    }
+
+    @Test
+    fun doesntTriggerGestureFinished_onThreeFingersSwipeInOtherDirections() {
+        assertStateAfterEvents(events = ThreeFingerGesture.swipeDown(), expectedState = NOT_STARTED)
+        assertStateAfterEvents(events = ThreeFingerGesture.swipeLeft(), expectedState = NOT_STARTED)
+        assertStateAfterEvents(
+            events = ThreeFingerGesture.swipeRight(),
+            expectedState = NOT_STARTED
+        )
+    }
+
+    @Test
+    fun doesntTriggerGestureFinished_onTwoFingersSwipe() {
+        assertStateAfterEvents(events = TwoFingerGesture.swipeUp(), expectedState = NOT_STARTED)
+    }
+
+    @Test
+    fun doesntTriggerGestureFinished_onFourFingersSwipe() {
+        assertStateAfterEvents(events = FourFingerGesture.swipeUp(), expectedState = NOT_STARTED)
+    }
+
+    private fun assertStateAfterEvents(events: List<MotionEvent>, expectedState: GestureState) {
+        events.forEach { gestureMonitor.processTouchpadEvent(it) }
+        assertThat(gestureState).isEqualTo(expectedState)
+    }
+}