From 25e0c530d22a063a2351b528f1fd786d30a8764b Mon Sep 17 00:00:00 2001
From: Massimo Carli <mcarli@google.com>
Date: Tue, 31 Jan 2023 23:47:26 +0000
Subject: [PATCH] Handle tranlucent strategy on back

The first opaque activity beneath a transparent one must not be
a finishing activity.
This prevents a wrong behaviour in case of permission requests
launched from activities after the user presses back.

Bug: 261721427
Test:  Test on apps that automatically display permission dialog
       when returning from a full screen (e.g. App Info screen)
       Run `atest SizeCompatTests`

Change-Id: I04fb0f30087fad137ee6733889bcb32498b2e898
---
 .../com/android/server/wm/ActivityRecord.java    |  4 ++++
 .../android/server/wm/LetterboxUiController.java |  7 ++++++-
 .../com/android/server/wm/SizeCompatTests.java   | 16 ++++++++++++++++
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/services/core/java/com/android/server/wm/ActivityRecord.java b/services/core/java/com/android/server/wm/ActivityRecord.java
index f7b9d8b2d8569..056b144a90b9b 100644
--- a/services/core/java/com/android/server/wm/ActivityRecord.java
+++ b/services/core/java/com/android/server/wm/ActivityRecord.java
@@ -3906,6 +3906,10 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
         }
     }
 
+    boolean isFinishing() {
+        return finishing;
+    }
+
     /**
      * This method is to only be called from the client via binder when the activity is destroyed
      * AND finished.
diff --git a/services/core/java/com/android/server/wm/LetterboxUiController.java b/services/core/java/com/android/server/wm/LetterboxUiController.java
index 9681789347cff..1aa0ec3c12801 100644
--- a/services/core/java/com/android/server/wm/LetterboxUiController.java
+++ b/services/core/java/com/android/server/wm/LetterboxUiController.java
@@ -105,6 +105,7 @@ import com.android.server.wm.LetterboxConfiguration.LetterboxBackgroundType;
 
 import java.io.PrintWriter;
 import java.util.function.BooleanSupplier;
+import java.util.function.Predicate;
 
 /** Controls behaviour of the letterbox UI for {@link mActivityRecord}. */
 // TODO(b/185262487): Improve test coverage of this class. Parts of it are tested in
@@ -114,6 +115,9 @@ import java.util.function.BooleanSupplier;
 // TODO(b/263021211): Consider renaming to more generic CompatUIController.
 final class LetterboxUiController {
 
+    private static final Predicate<ActivityRecord> FIRST_OPAQUE_NOT_FINISHING_ACTIVITY_PREDICATE =
+            activityRecord -> activityRecord.fillsParent() && !activityRecord.isFinishing();
+
     private static final String TAG = TAG_WITH_CLASS_NAME ? "LetterboxUiController" : TAG_ATM;
 
     private static final float UNDEFINED_ASPECT_RATIO = 0f;
@@ -1390,7 +1394,8 @@ final class LetterboxUiController {
             return;
         }
         final ActivityRecord firstOpaqueActivityBeneath = mActivityRecord.getTask().getActivity(
-                ActivityRecord::fillsParent, mActivityRecord, false /* includeBoundary */,
+                FIRST_OPAQUE_NOT_FINISHING_ACTIVITY_PREDICATE /* callback */,
+                mActivityRecord /* boundary */, false /* includeBoundary */,
                 true /* traverseTopToBottom */);
         if (firstOpaqueActivityBeneath == null) {
             // We skip letterboxing if the translucent activity doesn't have any opaque
diff --git a/services/tests/wmtests/src/com/android/server/wm/SizeCompatTests.java b/services/tests/wmtests/src/com/android/server/wm/SizeCompatTests.java
index fb5fda16408ed..2c4f1663153cc 100644
--- a/services/tests/wmtests/src/com/android/server/wm/SizeCompatTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/SizeCompatTests.java
@@ -254,6 +254,22 @@ public class SizeCompatTests extends WindowTestsBase {
         assertFalse(translucentActivity.inSizeCompatMode());
     }
 
+    @Test
+    public void testCheckOpaqueIsLetterboxedWhenStrategyIsApplied() {
+        mWm.mLetterboxConfiguration.setTranslucentLetterboxingOverrideEnabled(true);
+        setUpDisplaySizeWithApp(2000, 1000);
+        prepareUnresizable(mActivity, SCREEN_ORIENTATION_PORTRAIT);
+        mActivity.mDisplayContent.setIgnoreOrientationRequest(true /* ignoreOrientationRequest */);
+        // Translucent Activity
+        final ActivityRecord translucentActivity = new ActivityBuilder(mAtm)
+                .setLaunchedFromUid(mActivity.getUid())
+                .build();
+        doReturn(false).when(translucentActivity).fillsParent();
+        spyOn(mActivity);
+        mTask.addChild(translucentActivity);
+        verify(mActivity).isFinishing();
+    }
+
     @Test
     public void testRestartProcessIfVisible() {
         setUpDisplaySizeWithApp(1000, 2500);