Have AMS.setFocusedActivityLocked() move the focus stack to the front

Bug: 19219490
Change-Id: I089c42a6cf6277f5975064103c9804c2ab05dcd6

3 files changed, 47 insertions, 42 deletions

diff --git a/services/core/java/com/android/server/am/ActivityManagerService.java b/services/core/java/com/android/server/am/ActivityManagerService.java
index 966dc88..008d718 100644
--- a/services/core/java/com/android/server/am/ActivityManagerService.java
+++ b/services/core/java/com/android/server/am/ActivityManagerService.java
@@ -2398,8 +2398,7 @@ public final class ActivityManagerService extends ActivityManagerNative
             } else {
                 finishRunningVoiceLocked();
             }
-            mStackSupervisor.setFocusedStack(r, reason + " setFocusedActivity");
-            if (r != null) {
+            if (r != null && mStackSupervisor.setFocusedStack(r, reason + " setFocusedActivity")) {
                 mWindowManager.setFocusedApp(r.appToken, true);
             }
             applyUpdateLockStateLocked(r);
@@ -2423,6 +2422,7 @@ public final class ActivityManagerService extends ActivityManagerNative
                 ActivityRecord r = stack.topRunningActivityLocked(null);
                 if (r != null) {
                     setFocusedActivityLocked(r, "setFocusedStack");
+                    mStackSupervisor.resumeTopActivitiesLocked(stack, null, null);
                 }
             }
         }
diff --git a/services/core/java/com/android/server/am/ActivityStack.java b/services/core/java/com/android/server/am/ActivityStack.java
index b51f862..2ecf801 100644
--- a/services/core/java/com/android/server/am/ActivityStack.java
+++ b/services/core/java/com/android/server/am/ActivityStack.java
@@ -496,11 +496,19 @@ final class ActivityStack {
 
     final void moveToFront(String reason) {
         if (isAttached()) {
+            final boolean homeStack = isHomeStack()
+                    || (mActivityContainer.mParentActivity != null
+                        && mActivityContainer.mParentActivity.isHomeActivity());
+
+            if (!homeStack) {
+                // Need to move this stack to the front before calling
+                // {@link ActivityStackSupervisor#moveHomeStack} below.
+                mStacks.remove(this);
+                mStacks.add(this);
+            }
             if (isOnHomeDisplay()) {
-                mStackSupervisor.moveHomeStack(isHomeStack(), reason);
+                mStackSupervisor.moveHomeStack(homeStack, reason);
             }
-            mStacks.remove(this);
-            mStacks.add(this);
             final TaskRecord task = topTask();
             if (task != null) {
                 mWindowManager.moveTaskToTop(task.taskId);
@@ -2580,7 +2588,6 @@ final class ActivityStack {
         if (top == null) {
             return false;
         }
-        stack.moveToFront(myReason);
         mService.setFocusedActivityLocked(top, myReason);
         return true;
     }
@@ -3654,8 +3661,7 @@ final class ActivityStack {
             }
         }
 
-        if (DEBUG_TRANSITION) Slog.v(TAG,
-                "Prepare to back transition: task=" + taskId);
+        if (DEBUG_TRANSITION) Slog.v(TAG, "Prepare to back transition: task=" + taskId);
 
         boolean prevIsHome = false;
         if (tr.isOverHomeStack()) {
diff --git a/services/core/java/com/android/server/am/ActivityStackSupervisor.java b/services/core/java/com/android/server/am/ActivityStackSupervisor.java
index 907381e..f6ef295 100644
--- a/services/core/java/com/android/server/am/ActivityStackSupervisor.java
+++ b/services/core/java/com/android/server/am/ActivityStackSupervisor.java
@@ -1541,25 +1541,27 @@ public final class ActivityStackSupervisor implements DisplayListener {
         return err;
     }
 
-    ActivityStack adjustStackFocus(ActivityRecord r, boolean newTask) {
+    ActivityStack computeStackFocus(ActivityRecord r, boolean newTask) {
         final TaskRecord task = r.task;
 
         // On leanback only devices we should keep all activities in the same stack.
         if (!mLeanbackOnlyDevice &&
                 (r.isApplicationActivity() || (task != null && task.isApplicationTask()))) {
+
+            ActivityStack stack;
+
             if (task != null) {
-                final ActivityStack taskStack = task.stack;
-                if (taskStack.isOnHomeDisplay()) {
-                    if (mFocusedStack != taskStack) {
-                        if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG, "adjustStackFocus: Setting " +
+                stack = task.stack;
+                if (stack.isOnHomeDisplay()) {
+                    if (mFocusedStack != stack) {
+                        if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG, "computeStackFocus: Setting " +
                                 "focused stack to r=" + r + " task=" + task);
-                        mFocusedStack = taskStack;
                     } else {
                         if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
-                            "adjustStackFocus: Focused stack already=" + mFocusedStack);
+                            "computeStackFocus: Focused stack already=" + mFocusedStack);
                     }
                 }
-                return taskStack;
+                return stack;
             }
 
             final ActivityContainer container = r.mInitialActivityContainer;
@@ -1572,43 +1574,41 @@ public final class ActivityStackSupervisor implements DisplayListener {
             if (mFocusedStack != mHomeStack && (!newTask ||
                     mFocusedStack.mActivityContainer.isEligibleForNewTasks())) {
                 if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
-                        "adjustStackFocus: Have a focused stack=" + mFocusedStack);
+                        "computeStackFocus: Have a focused stack=" + mFocusedStack);
                 return mFocusedStack;
             }
 
             final ArrayList<ActivityStack> homeDisplayStacks = mHomeStack.mStacks;
             for (int stackNdx = homeDisplayStacks.size() - 1; stackNdx >= 0; --stackNdx) {
-                final ActivityStack stack = homeDisplayStacks.get(stackNdx);
+                stack = homeDisplayStacks.get(stackNdx);
                 if (!stack.isHomeStack()) {
                     if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
-                            "adjustStackFocus: Setting focused stack=" + stack);
-                    mFocusedStack = stack;
-                    return mFocusedStack;
+                            "computeStackFocus: Setting focused stack=" + stack);
+                    return stack;
                 }
             }
 
             // Need to create an app stack for this user.
-            mFocusedStack = createStackOnDisplay(getNextStackId(), Display.DEFAULT_DISPLAY);
-            if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG, "adjustStackFocus: New stack r=" + r +
-                    " stackId=" + mFocusedStack.mStackId);
-            return mFocusedStack;
+            stack = createStackOnDisplay(getNextStackId(), Display.DEFAULT_DISPLAY);
+            if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG, "computeStackFocus: New stack r=" + r +
+                    " stackId=" + stack.mStackId);
+            return stack;
         }
         return mHomeStack;
     }
 
-    void setFocusedStack(ActivityRecord r, String reason) {
-        if (r != null) {
-            final TaskRecord task = r.task;
-            boolean isHomeActivity = !r.isApplicationActivity();
-            if (!isHomeActivity && task != null) {
-                isHomeActivity = !task.isApplicationTask();
-            }
-            if (!isHomeActivity && task != null) {
-                final ActivityRecord parent = task.stack.mActivityContainer.mParentActivity;
-                isHomeActivity = parent != null && parent.isHomeActivity();
-            }
-            moveHomeStack(isHomeActivity, reason);
+    boolean setFocusedStack(ActivityRecord r, String reason) {
+        if (r == null) {
+            // Not sure what you are trying to do, but it is not going to work...
+            return false;
         }
+        final TaskRecord task = r.task;
+        if (task == null || task.stack == null) {
+            Slog.w(TAG, "Can't set focus stack for r=" + r + " task=" + task);
+            return false;
+        }
+        task.stack.moveToFront(reason);
+        return true;
     }
 
     final int startActivityUncheckedLocked(final ActivityRecord r, ActivityRecord sourceRecord,
@@ -2082,10 +2082,9 @@ public final class ActivityStackSupervisor implements DisplayListener {
                 return ActivityManager.START_RETURN_LOCK_TASK_MODE_VIOLATION;
             }
             newTask = true;
-            targetStack = adjustStackFocus(r, newTask);
-            if (!launchTaskBehind) {
-                targetStack.moveToFront("startingNewTask");
-            }
+            targetStack = computeStackFocus(r, newTask);
+            targetStack.moveToFront("startingNewTask");
+
             if (reuseTask == null) {
                 r.setTask(targetStack.createTaskRecord(getNextTaskId(),
                         newTaskInfo != null ? newTaskInfo : r.info,
@@ -2206,7 +2205,7 @@ public final class ActivityStackSupervisor implements DisplayListener {
             // This not being started from an existing activity, and not part
             // of a new task...  just put it in the top task, though these days
             // this case should never happen.
-            targetStack = adjustStackFocus(r, newTask);
+            targetStack = computeStackFocus(r, newTask);
             targetStack.moveToFront("addingToTopTask");
             ActivityRecord prev = targetStack.topActivity();
             r.setTask(prev != null ? prev.task : targetStack.createTaskRecord(getNextTaskId(),