From 529c8e4cf24375ca21b5d61fb6b34e7010d6edad Mon Sep 17 00:00:00 2001
From: Winson <winsonc@google.com>
Date: Tue, 17 May 2016 11:08:40 -0700
Subject: [PATCH] Mark occluded home stack as invisible.
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- The home stack is still visible when a translucent activity (like
  dialer) is on top, which caused us to use the logic path that just
  tries to launch the next task.  However, that path does not reload
  the stack state (since the activity stack generally doesn’t change
  while Recents is visible) so it was always launching the already top
  activity.  The new check ensures that we start the activity anew
  as if it was coming from an occluding app.

Bug: 28767764
Change-Id: Iec0fdc0957e5070cec532c5de5cba3454c906a3b
---
 core/java/android/app/ActivityManager.java         |  4 ++++
 .../systemui/recents/misc/SystemServicesProxy.java | 14 +++++++++++---
 .../android/server/am/ActivityStackSupervisor.java |  5 ++++-
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/core/java/android/app/ActivityManager.java b/core/java/android/app/ActivityManager.java
index 8a92b5477caf0..e3035daf0fd34 100644
--- a/core/java/android/app/ActivityManager.java
+++ b/core/java/android/app/ActivityManager.java
@@ -2370,6 +2370,8 @@ public class ActivityManager {
         public int displayId;
         public int userId;
         public boolean visible;
+        // Index of the stack in the display's stack list, can be used for comparison of stack order
+        public int position;
 
         @Override
         public int describeContents() {
@@ -2397,6 +2399,7 @@ public class ActivityManager {
             dest.writeInt(displayId);
             dest.writeInt(userId);
             dest.writeInt(visible ? 1 : 0);
+            dest.writeInt(position);
             if (topActivity != null) {
                 dest.writeInt(1);
                 topActivity.writeToParcel(dest, 0);
@@ -2426,6 +2429,7 @@ public class ActivityManager {
             displayId = source.readInt();
             userId = source.readInt();
             visible = source.readInt() > 0;
+            position = source.readInt();
             if (source.readInt() > 0) {
                 topActivity = ComponentName.readFromParcel(source);
             }
diff --git a/packages/SystemUI/src/com/android/systemui/recents/misc/SystemServicesProxy.java b/packages/SystemUI/src/com/android/systemui/recents/misc/SystemServicesProxy.java
index 15bc2796e53e0..64f83a9389289 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/misc/SystemServicesProxy.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/misc/SystemServicesProxy.java
@@ -371,11 +371,19 @@ public class SystemServicesProxy {
         try {
             ActivityManager.StackInfo stackInfo = mIam.getStackInfo(
                     ActivityManager.StackId.HOME_STACK_ID);
+            ActivityManager.StackInfo fullscreenStackInfo = mIam.getStackInfo(
+                    ActivityManager.StackId.FULLSCREEN_WORKSPACE_STACK_ID);
             ComponentName topActivity = stackInfo.topActivity;
-            if (isHomeStackVisible != null) {
-                isHomeStackVisible.value = stackInfo.visible;
+            boolean homeStackVisibleNotOccluded = stackInfo.visible;
+            if (fullscreenStackInfo != null) {
+                boolean isFullscreenStackOccludingHome = fullscreenStackInfo.visible &&
+                        fullscreenStackInfo.position > stackInfo.position;
+                homeStackVisibleNotOccluded &= !isFullscreenStackOccludingHome;
             }
-            return (stackInfo.visible && topActivity != null
+            if (isHomeStackVisible != null) {
+                isHomeStackVisible.value = homeStackVisibleNotOccluded;
+            }
+            return (homeStackVisibleNotOccluded && topActivity != null
                     && topActivity.getPackageName().equals(RecentsImpl.RECENTS_PACKAGE)
                     && (topActivity.getClassName().equals(RecentsImpl.RECENTS_ACTIVITY)
                         || topActivity.getClassName().equals(RecentsTvImpl.RECENTS_TV_ACTIVITY)));
diff --git a/services/core/java/com/android/server/am/ActivityStackSupervisor.java b/services/core/java/com/android/server/am/ActivityStackSupervisor.java
index 0baca9e3db15d..ded9aa89382ee 100644
--- a/services/core/java/com/android/server/am/ActivityStackSupervisor.java
+++ b/services/core/java/com/android/server/am/ActivityStackSupervisor.java
@@ -123,7 +123,6 @@ import static android.app.ActivityManager.StackId.PINNED_STACK_ID;
 import static android.content.Intent.FLAG_ACTIVITY_MULTIPLE_TASK;
 import static android.content.Intent.FLAG_ACTIVITY_NEW_TASK;
 import static android.content.pm.ActivityInfo.FLAG_SHOW_FOR_ALL_USERS;
-import static android.content.pm.ActivityInfo.RESIZE_MODE_FORCE_RESIZEABLE;
 import static android.content.pm.PackageManager.PERMISSION_GRANTED;
 import static android.os.Trace.TRACE_TAG_ACTIVITY_MANAGER;
 import static com.android.server.am.ActivityManagerDebugConfig.DEBUG_ALL;
@@ -3406,12 +3405,16 @@ public final class ActivityStackSupervisor implements DisplayListener {
     }
 
     private StackInfo getStackInfoLocked(ActivityStack stack) {
+        final ActivityDisplay display = mActivityDisplays.get(Display.DEFAULT_DISPLAY);
         StackInfo info = new StackInfo();
         mWindowManager.getStackBounds(stack.mStackId, info.bounds);
         info.displayId = Display.DEFAULT_DISPLAY;
         info.stackId = stack.mStackId;
         info.userId = stack.mCurrentUser;
         info.visible = stack.getStackVisibilityLocked(null) == STACK_VISIBLE;
+        info.position = display != null
+                ? display.mStacks.indexOf(stack)
+                : 0;
 
         ArrayList<TaskRecord> tasks = stack.getAllTasks();
         final int numTasks = tasks.size();