From ae3b07716119794a7c5d0f6ea127c29c428979ba Mon Sep 17 00:00:00 2001
From: Vishnu Nair <vishnun@google.com>
Date: Thu, 19 Mar 2020 16:55:25 -0700
Subject: [PATCH] Update shadow radius if the task has no visible children

Test: enter pip and lock phone, then unlock phone
Test: go/wm-smoke
Fixes: 150461623

Change-Id: I9cba48527e29c6acb9139689c0e3fd3e42ffd955
---
 .../core/java/com/android/server/wm/Task.java | 40 +++++++++++++------
 1 file changed, 27 insertions(+), 13 deletions(-)

diff --git a/services/core/java/com/android/server/wm/Task.java b/services/core/java/com/android/server/wm/Task.java
index f826deb6926a6..569d64cf4f398 100644
--- a/services/core/java/com/android/server/wm/Task.java
+++ b/services/core/java/com/android/server/wm/Task.java
@@ -1918,7 +1918,6 @@ class Task extends WindowContainer<WindowContainer> {
         super.onConfigurationChanged(newParentConfig);
         if (wasInMultiWindowMode != inMultiWindowMode()) {
             mStackSupervisor.scheduleUpdateMultiWindowMode(this);
-            updateShadowsRadius(isFocused(), getPendingTransaction());
         }
 
         final int newWinMode = getWindowingMode();
@@ -3320,6 +3319,7 @@ class Task extends WindowContainer<WindowContainer> {
         }
 
         updateSurfaceCrop();
+        updateShadowsRadius(isFocused(), getPendingTransaction());
 
         if (mDimmer.updateDims(getPendingTransaction(), mTmpDimBoundsRect)) {
             scheduleAnimation();
@@ -4140,27 +4140,41 @@ class Task extends WindowContainer<WindowContainer> {
         return mDisplayContent.mCurrentFocus.getTask() == this;
     }
 
+    /**
+     * @return true if the task is visible and has at least one visible child.
+     */
+    private boolean hasVisibleChildren() {
+        if (!isAttached() || isForceHidden()) {
+            return false;
+        }
+
+        return getActivity(ActivityRecord::isVisible) != null;
+    }
+
     /**
      * @return the desired shadow radius in pixels for the current task.
      */
     private float getShadowRadius(boolean taskIsFocused) {
-        if (mDisplayContent == null) {
+        int elevation = 0;
+
+        // Get elevation for a specific windowing mode.
+        if (inPinnedWindowingMode()) {
+            elevation = PINNED_WINDOWING_MODE_ELEVATION_IN_DIP;
+        } else if (ENABLE_FREEFORM_COMPOSITOR_SHADOWS && inFreeformWindowingMode()) {
+            // TODO(b/149585281) remove when root task has the correct bounds for freeform
+            elevation = taskIsFocused
+                    ? DECOR_SHADOW_FOCUSED_HEIGHT_IN_DIP : DECOR_SHADOW_UNFOCUSED_HEIGHT_IN_DIP;
+        } else {
+            // For all other windowing modes, do not draw a shadow.
             return 0;
         }
 
-        if (inPinnedWindowingMode()) {
-            return dipToPixel(PINNED_WINDOWING_MODE_ELEVATION_IN_DIP,
-                    mDisplayContent.getDisplayMetrics());
-        }
-        // TODO(b/149585281) remove when root task has the correct bounds for freeform
-        if (ENABLE_FREEFORM_COMPOSITOR_SHADOWS && inFreeformWindowingMode()) {
-            final int elevation = taskIsFocused
-                    ? DECOR_SHADOW_FOCUSED_HEIGHT_IN_DIP : DECOR_SHADOW_UNFOCUSED_HEIGHT_IN_DIP;
-            return dipToPixel(elevation, mDisplayContent.getDisplayMetrics());
+        // If the task has no visible children, do not draw a shadow.
+        if (!hasVisibleChildren()) {
+            return 0;
         }
 
-        // For all other windowing modes, do not draw a shadow.
-        return 0;
+        return dipToPixel(elevation, getDisplayContent().getDisplayMetrics());
     }
 
     /**