Fixed bug with activity behind non-fullscreen activity not displaying

Regression introduced in I5bf77063252a5abae4e327f6fc42e607091749f9
where some policy for visiblity of tasks in freeform stacks was
added which ended up applying to other types of stacks. We now limit
the policy to just freeform tasks.

Bug: 23957523
Change-Id: Ib6fad5a89e22d64adf0e52b9e8ed5f2239488245

diff --git a/services/core/java/com/android/server/am/ActivityStack.java b/services/core/java/com/android/server/am/ActivityStack.java
index 751acb6..a8a0073 100644 (file)
--- a/services/core/java/com/android/server/am/ActivityStack.java
+++ b/services/core/java/com/android/server/am/ActivityStack.java
@@ -1400,16 +1400,14 @@ final class ActivityStack {
         // If the top activity is not fullscreen, then we need to
         // make sure any activities under it are now visible.
         boolean aboveTop = true;
-        boolean behindFullscreen = !isStackVisibleLocked();
+        final boolean stackInvisible = !isStackVisibleLocked();
+        boolean behindFullscreenActivity = stackInvisible;
         boolean noStackActivityResumed = (isInStackLocked(starting) == null);
 
         for (int taskNdx = mTaskHistory.size() - 1; taskNdx >= 0; --taskNdx) {
             final TaskRecord task = mTaskHistory.get(taskNdx);
             final ArrayList<ActivityRecord> activities = task.mActivities;
-            // Set to true if an activity in this task is fullscreen thereby hiding other
-            // activities in the same task. Initialized to the same value as behindFullscreen
-            // which represent if the entire task/stack is behind another fullscreen task/stack.
-            boolean behindFullscreenActivity = behindFullscreen;
+
             for (int activityNdx = activities.size() - 1; activityNdx >= 0; --activityNdx) {
                 final ActivityRecord r = activities.get(activityNdx);
                 if (r.finishing) {
@@ -1507,18 +1505,18 @@ final class ActivityStack {
                         // At this point, nothing else needs to be shown in this task.
                         behindFullscreenActivity = true;
                         if (DEBUG_VISIBILITY) Slog.v(TAG_VISIBILITY, "Fullscreen: at " + r
-                                + " behindFullscreen=" + behindFullscreen
+                                + " stackInvisible=" + stackInvisible
                                 + " behindFullscreenActivity=" + behindFullscreenActivity);
                     } else if (!isHomeStack() && r.frontOfTask && task.isOverHomeStack()) {
                         behindFullscreenActivity = true;
                         if (DEBUG_VISIBILITY) Slog.v(TAG_VISIBILITY, "Showing home: at " + r
-                                + " behindFullscreen=" + behindFullscreen
+                                + " stackInvisible=" + stackInvisible
                                 + " behindFullscreenActivity=" + behindFullscreenActivity);
                     }
                 } else {
                     if (DEBUG_VISIBILITY) Slog.v(TAG_VISIBILITY,
                             "Make invisible? " + r + " finishing=" + r.finishing
-                            + " state=" + r.state + " behindFullscreen=" + behindFullscreen
+                            + " state=" + r.state + " stackInvisible=" + stackInvisible
                             + " behindFullscreenActivity=" + behindFullscreenActivity);
                     // Now for any activities that aren't visible to the user, make
                     // sure they no longer are keeping the screen frozen.
@@ -1566,9 +1564,12 @@ final class ActivityStack {
                     }
                 }
             }
-            // Factoring if the previous task is fullscreen there by affecting the visibility of
-            // task behind it.
-            behindFullscreen |= task.mFullscreen;
+            if (mStackId == FREEFORM_WORKSPACE_STACK_ID) {
+                // The visibility of tasks and the activities they contain in freeform stack are
+                // determined individually unlike other stacks where the visibility or fullscreen
+                // status of an activity in a previous task affects other.
+                behindFullscreenActivity = stackInvisible;
+            }
         }
 
         if (mTranslucentActivityWaiting != null &&