From 7b2c3db83afc15a5baf8deb09ed47a6fb863f7da Mon Sep 17 00:00:00 2001
From: shannonchen <shannonchen@google.com>
Date: Mon, 18 Apr 2022 20:34:03 +0000
Subject: [PATCH] Make GameSessionTrampolineActivity invisible

This change adds a new theme to prevent
GameSessionTrampolineActivity from displaying
any UI, which in turn delegates the
decision of whether or not to show things
like the system bars to the delegate
activity. This change also disables
transition animations for the trampoline
activity, to prevent them from causing
flickering.

Bug: 229757156
Test: manual testing using GMS dashboard
Change-Id: I82e0ede2e9f0b334fd01e958eab0736042119e84
---
 .../games/GameSessionTrampolineActivity.java     |  2 ++
 core/res/AndroidManifest.xml                     |  2 +-
 core/res/res/values/themes.xml                   | 16 ++++++++++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/core/java/android/service/games/GameSessionTrampolineActivity.java b/core/java/android/service/games/GameSessionTrampolineActivity.java
index 3d97d0f59b332..eec7ac6ff4474 100644
--- a/core/java/android/service/games/GameSessionTrampolineActivity.java
+++ b/core/java/android/service/games/GameSessionTrampolineActivity.java
@@ -60,6 +60,7 @@ public final class GameSessionTrampolineActivity extends Activity {
                     FUTURE_KEY);
             future.completeExceptionally(e);
             finish();
+            overridePendingTransition(0, 0);
         }
     }
 
@@ -74,5 +75,6 @@ public final class GameSessionTrampolineActivity extends Activity {
                 FUTURE_KEY);
         future.complete(new GameSessionActivityResult(resultCode, data));
         finish();
+        overridePendingTransition(0, 0);
     }
 }
diff --git a/core/res/AndroidManifest.xml b/core/res/AndroidManifest.xml
index 4075c5f4d8ae4..0a2b01998ca97 100644
--- a/core/res/AndroidManifest.xml
+++ b/core/res/AndroidManifest.xml
@@ -6790,7 +6790,7 @@
                   android:excludeFromRecents="true"
                   android:exported="true"
                   android:permission="android.permission.MANAGE_GAME_ACTIVITY"
-                  android:theme="@style/Theme.Translucent.NoTitleBar">
+                  android:theme="@style/Theme.GameSessionTrampoline">
         </activity>
 
         <receiver android:name="com.android.server.BootReceiver"
diff --git a/core/res/res/values/themes.xml b/core/res/res/values/themes.xml
index bf42da0803905..a60862b74e15c 100644
--- a/core/res/res/values/themes.xml
+++ b/core/res/res/values/themes.xml
@@ -894,6 +894,22 @@ please see themes_device_defaults.xml.
     <!-- @hide Special theme for the default system Activity-based Alert dialogs. -->
     <style name="Theme.Dialog.Confirmation" parent="Theme.DeviceDefault.Dialog.Alert.DayNight" />
 
+    <!-- @hide Theme for GameSessionTrampolineActivity that prevents showing UI and activity
+         transitions. -->
+    <style name="Theme.GameSessionTrampoline">
+        <item name="backgroundDimEnabled">false</item>
+        <item name="colorBackgroundCacheHint">@null</item>
+        <item name="navigationBarColor">@color/transparent</item>
+        <item name="statusBarColor">@color/transparent</item>
+        <item name="windowAnimationStyle">@null</item>
+        <item name="windowBackground">@null</item>
+        <item name="windowContentOverlay">@null</item>
+        <item name="windowDrawsSystemBarBackgrounds">true</item>
+        <item name="windowIsFloating">true</item>
+        <item name="windowIsTranslucent">true</item>
+        <item name="windowNoTitle">true</item>
+    </style>
+
     <!-- Theme for a window that looks like a toast. -->
     <style name="Theme.Toast" parent="Theme.DeviceDefault.Dialog">
         <item name="windowBackground">?attr/toastFrameBackground</item>