From 934420353154cb9e694f49dd1d5f5267d971e8dc Mon Sep 17 00:00:00 2001
From: Winson Chung <winsonc@google.com>
Date: Tue, 4 Dec 2018 13:24:29 -0800
Subject: [PATCH] When creating a stack for the recents animation, ensure it is
 not top most

- When the avoidMoveToFront flag is set on the activity options (used only
  for the recents animation), avoid creating a stack for the new recents
  activity in the top, as this changes the visibility of the front most
  task that we are animating from.

Bug: 119661847
Test: adb shell am force-stop com.google.android.apps.nexuslauncher
      then try and swipe up

Change-Id: I06bcb304f5c4e7fd3a7b1d9b72d8e119b865f448
---
 .../com/android/server/wm/ActivityStarter.java  |  3 ++-
 .../com/android/server/wm/RecentsAnimation.java | 17 +++++++++++++----
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/services/core/java/com/android/server/wm/ActivityStarter.java b/services/core/java/com/android/server/wm/ActivityStarter.java
index bc2136ebcf15d..c75a85fc586a6 100644
--- a/services/core/java/com/android/server/wm/ActivityStarter.java
+++ b/services/core/java/com/android/server/wm/ActivityStarter.java
@@ -2506,8 +2506,9 @@ class ActivityStarter {
             // full resolution.
             mLaunchParams.mPreferredDisplayId =
                     mPreferredDisplayId != DEFAULT_DISPLAY ? mPreferredDisplayId : INVALID_DISPLAY;
+            final boolean onTop = aOptions == null || !aOptions.getAvoidMoveToFront();
             final ActivityStack stack =
-                    mRootActivityContainer.getLaunchStack(r, aOptions, task, ON_TOP, mLaunchParams);
+                    mRootActivityContainer.getLaunchStack(r, aOptions, task, onTop, mLaunchParams);
             mLaunchParams.mPreferredDisplayId = mPreferredDisplayId;
             return stack;
         }
diff --git a/services/core/java/com/android/server/wm/RecentsAnimation.java b/services/core/java/com/android/server/wm/RecentsAnimation.java
index 942218244505f..7dcfa12ca88e7 100644
--- a/services/core/java/com/android/server/wm/RecentsAnimation.java
+++ b/services/core/java/com/android/server/wm/RecentsAnimation.java
@@ -107,7 +107,7 @@ class RecentsAnimation implements RecentsAnimationCallbacks,
                 && recentsComponent.equals(intent.getComponent())
                         ? ACTIVITY_TYPE_RECENTS
                         : ACTIVITY_TYPE_HOME;
-        final ActivityStack targetStack = mDefaultDisplay.getStack(WINDOWING_MODE_UNDEFINED,
+        ActivityStack targetStack = mDefaultDisplay.getStack(WINDOWING_MODE_UNDEFINED,
                 mTargetActivityType);
         ActivityRecord targetActivity = getTargetActivity(targetStack, intent.getComponent());
         final boolean hasExistingActivity = targetActivity != null;
@@ -153,7 +153,7 @@ class RecentsAnimation implements RecentsAnimationCallbacks,
                             "startRecentsActivity");
                 }
             } else {
-                // No recents activity
+                // No recents activity, create the new recents activity bottom most
                 ActivityOptions options = ActivityOptions.makeBasic();
                 options.setLaunchActivityType(mTargetActivityType);
                 options.setAvoidMoveToFront();
@@ -166,11 +166,20 @@ class RecentsAnimation implements RecentsAnimationCallbacks,
                         .setActivityOptions(SafeActivityOptions.fromBundle(options.toBundle()))
                         .setMayWait(userId)
                         .execute();
+
+                // Move the recents activity into place for the animation
+                targetActivity = mDefaultDisplay.getStack(WINDOWING_MODE_UNDEFINED,
+                        mTargetActivityType).getTopActivity();
+                targetStack = targetActivity.getActivityStack();
+                mDefaultDisplay.moveStackBehindBottomMostVisibleStack(targetStack);
+                if (DEBUG) {
+                    Slog.d(TAG, "Moved stack=" + targetStack + " behind stack="
+                            + mDefaultDisplay.getStackAbove(targetStack));
+                }
+
                 mWindowManager.prepareAppTransition(TRANSIT_NONE, false);
                 mWindowManager.executeAppTransition();
 
-                targetActivity = mDefaultDisplay.getStack(WINDOWING_MODE_UNDEFINED,
-                        mTargetActivityType).getTopActivity();
 
                 // TODO: Maybe wait for app to draw in this particular case?