From e644ff610220c9f8196cfa982d735e678b121bdc Mon Sep 17 00:00:00 2001
From: Pablo Gamito <pablogamito@google.com>
Date: Wed, 24 Nov 2021 19:57:52 +0100
Subject: [PATCH] Don't set background color if TDA doesn't have a valid
 surface

This is something that sometimes occurs in tests since the detaching of the TDA in not necesseraily synchronized with animations

Test: atest CtsWindowManagerDeviceTestCases:MultiDisplaySystemDecorationTests
Bug: 207667555
Change-Id: I9881453ba14cba4f219861ec4449f2baa8058b57
---
 .../com/android/server/wm/TaskDisplayArea.java   | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/services/core/java/com/android/server/wm/TaskDisplayArea.java b/services/core/java/com/android/server/wm/TaskDisplayArea.java
index 600545e41e475..4af0ecc164142 100644
--- a/services/core/java/com/android/server/wm/TaskDisplayArea.java
+++ b/services/core/java/com/android/server/wm/TaskDisplayArea.java
@@ -905,18 +905,24 @@ final class TaskDisplayArea extends DisplayArea<WindowContainer> {
         mBackgroundColor = colorInt;
         Color color = Color.valueOf(colorInt);
         mColorLayerCounter++;
-        getPendingTransaction()
-                .setColor(mSurfaceControl, new float[]{color.red(), color.green(), color.blue()});
 
-        scheduleAnimation();
+        // Only apply the background color if the TDA is actually attached and has a valid surface
+        // to set the background color on. We still want to keep track of the background color state
+        // even if we are not showing it for when/if the TDA is reattached and gets a valid surface
+        if (mSurfaceControl != null) {
+            getPendingTransaction()
+                    .setColor(mSurfaceControl,
+                            new float[]{color.red(), color.green(), color.blue()});
+            scheduleAnimation();
+        }
     }
 
     void clearBackgroundColor() {
         mColorLayerCounter--;
 
         // Only clear the color layer if we have received the same amounts of clear as set
-        // requests.
-        if (mColorLayerCounter == 0) {
+        // requests and TDA has a non null surface control (i.e. is attached)
+        if (mColorLayerCounter == 0 && mSurfaceControl != null) {
             getPendingTransaction().unsetColor(mSurfaceControl);
             scheduleAnimation();
         }