From 83e901d8d7c5780113455d1ddacdf3b0c475efd0 Mon Sep 17 00:00:00 2001
From: Shan Huang <shanh@google.com>
Date: Mon, 28 Mar 2022 21:25:03 +0000
Subject: [PATCH] Fix back taking multiple swipes.

Bug: 226417634
Bug: 226723586
Test: Try swiping back on multiple devices. It seems it's easier to
repro on bluechip devices. A good test case for me was to bring up and
dismiss all apps folder repeatedly on a p22 device.

Change-Id: I4dc5f5ee1f67822206a5e0442f26a52114cf63f0
---
 .../src/com/android/wm/shell/back/BackAnimation.java     | 9 ++++++++-
 .../android/wm/shell/back/BackAnimationController.java   | 9 +++++----
 .../wm/shell/back/BackAnimationControllerTest.java       | 6 ++++++
 .../navigationbar/gestural/NavigationBarEdgePanel.java   | 4 +++-
 4 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimation.java b/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimation.java
index 7cf359729ee88..e71a59d267405 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimation.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimation.java
@@ -16,6 +16,7 @@
 
 package com.android.wm.shell.back;
 
+import android.view.KeyEvent;
 import android.view.MotionEvent;
 import android.window.BackEvent;
 
@@ -29,8 +30,14 @@ public interface BackAnimation {
 
     /**
      * Called when a {@link MotionEvent} is generated by a back gesture.
+     *
+     * @param event the original {@link MotionEvent}
+     * @param action the original {@link KeyEvent#getAction()} when the event was dispatched to
+     *               the process. This is forwarded separately because the input pipeline may mutate
+     *               the {#event} action state later.
+     * @param swipeEdge the edge from which the swipe begins.
      */
-    void onBackMotion(MotionEvent event, @BackEvent.SwipeEdge int swipeEdge);
+    void onBackMotion(MotionEvent event, int action, @BackEvent.SwipeEdge int swipeEdge);
 
     /**
      * Sets whether the back gesture is past the trigger threshold or not.
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimationController.java b/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimationController.java
index 08cb252cdf432..93ee3f5378e8f 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimationController.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/back/BackAnimationController.java
@@ -138,8 +138,9 @@ public class BackAnimationController implements RemoteCallable<BackAnimationCont
         }
 
         @Override
-        public void onBackMotion(MotionEvent event, @BackEvent.SwipeEdge int swipeEdge) {
-            mShellExecutor.execute(() -> onMotionEvent(event, swipeEdge));
+        public void onBackMotion(
+                MotionEvent event, int action, @BackEvent.SwipeEdge int swipeEdge) {
+            mShellExecutor.execute(() -> onMotionEvent(event, action, swipeEdge));
         }
 
         @Override
@@ -209,13 +210,13 @@ public class BackAnimationController implements RemoteCallable<BackAnimationCont
      * Called when a new motion event needs to be transferred to this
      * {@link BackAnimationController}
      */
-    public void onMotionEvent(MotionEvent event, @BackEvent.SwipeEdge int swipeEdge) {
-        int action = event.getActionMasked();
+    public void onMotionEvent(MotionEvent event, int action, @BackEvent.SwipeEdge int swipeEdge) {
         if (action == MotionEvent.ACTION_DOWN) {
             initAnimation(event);
         } else if (action == MotionEvent.ACTION_MOVE) {
             onMove(event, swipeEdge);
         } else if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_CANCEL) {
+            ProtoLog.d(WM_SHELL_BACK_PREVIEW, "Finishing gesture with event: %s", event);
             onGestureFinished();
         }
     }
diff --git a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/back/BackAnimationControllerTest.java b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/back/BackAnimationControllerTest.java
index 05230a9417bb3..7c1fae3a849b4 100644
--- a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/back/BackAnimationControllerTest.java
+++ b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/back/BackAnimationControllerTest.java
@@ -118,6 +118,7 @@ public class BackAnimationControllerTest {
                 BackNavigationInfo.TYPE_CROSS_ACTIVITY);
         mController.onMotionEvent(
                 MotionEvent.obtain(0, 0, MotionEvent.ACTION_DOWN, 0, 0, 0),
+                MotionEvent.ACTION_DOWN,
                 BackEvent.EDGE_LEFT);
         verify(mTransaction).setBuffer(screenshotSurface, hardwareBuffer);
         verify(mTransaction).setVisibility(screenshotSurface, true);
@@ -133,9 +134,11 @@ public class BackAnimationControllerTest {
                 BackNavigationInfo.TYPE_CROSS_ACTIVITY);
         mController.onMotionEvent(
                 MotionEvent.obtain(0, 0, MotionEvent.ACTION_DOWN, 0, 0, 0),
+                MotionEvent.ACTION_DOWN,
                 BackEvent.EDGE_LEFT);
         mController.onMotionEvent(
                 MotionEvent.obtain(10, 0, MotionEvent.ACTION_MOVE, 100, 100, 0),
+                MotionEvent.ACTION_MOVE,
                 BackEvent.EDGE_LEFT);
         verify(mTransaction).setPosition(animationTarget.leash, 100, 100);
         verify(mTransaction, atLeastOnce()).apply();
@@ -151,12 +154,14 @@ public class BackAnimationControllerTest {
         // Check that back start is dispatched.
         mController.onMotionEvent(
                 MotionEvent.obtain(0, 0, MotionEvent.ACTION_DOWN, 0, 0, 0),
+                MotionEvent.ACTION_DOWN,
                 BackEvent.EDGE_LEFT);
         verify(mIOnBackInvokedCallback).onBackStarted();
 
         // Check that back progress is dispatched.
         mController.onMotionEvent(
                 MotionEvent.obtain(10, 0, MotionEvent.ACTION_MOVE, 100, 100, 0),
+                MotionEvent.ACTION_MOVE,
                 BackEvent.EDGE_LEFT);
         ArgumentCaptor<BackEvent> backEventCaptor = ArgumentCaptor.forClass(BackEvent.class);
         verify(mIOnBackInvokedCallback).onBackProgressed(backEventCaptor.capture());
@@ -166,6 +171,7 @@ public class BackAnimationControllerTest {
         mController.setTriggerBack(true);   // Fake trigger back
         mController.onMotionEvent(
                 MotionEvent.obtain(0, 0, MotionEvent.ACTION_UP, 0, 0, 0),
+                MotionEvent.ACTION_UP,
                 BackEvent.EDGE_LEFT);
         verify(mIOnBackInvokedCallback).onBackInvoked();
     }
diff --git a/packages/SystemUI/src/com/android/systemui/navigationbar/gestural/NavigationBarEdgePanel.java b/packages/SystemUI/src/com/android/systemui/navigationbar/gestural/NavigationBarEdgePanel.java
index a1258df7a12c1..03652412c129c 100644
--- a/packages/SystemUI/src/com/android/systemui/navigationbar/gestural/NavigationBarEdgePanel.java
+++ b/packages/SystemUI/src/com/android/systemui/navigationbar/gestural/NavigationBarEdgePanel.java
@@ -480,7 +480,9 @@ public class NavigationBarEdgePanel extends View implements NavigationEdgeBackPl
     public void onMotionEvent(MotionEvent event) {
         if (mBackAnimation != null) {
             mBackAnimation.onBackMotion(
-                    event, mIsLeftPanel ? BackEvent.EDGE_LEFT : BackEvent.EDGE_RIGHT);
+                    event,
+                    event.getActionMasked(),
+                    mIsLeftPanel ? BackEvent.EDGE_LEFT : BackEvent.EDGE_RIGHT);
         }
         if (mVelocityTracker == null) {
             mVelocityTracker = VelocityTracker.obtain();