Merge "Start using LetterboxAppearanceCalculator in SysUI" into tm-qpr-dev

7 files changed, 500 insertions, 31 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacks.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacks.java
index eda3446c8cb6..f4b7772a1453 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacks.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacks.java
@@ -57,10 +57,8 @@ import com.android.systemui.keyguard.WakefulnessLifecycle;
 import com.android.systemui.qs.QSPanelController;
 import com.android.systemui.shade.NotificationPanelView;
 import com.android.systemui.shade.NotificationPanelViewController;
-import com.android.systemui.shade.NotificationShadeWindowView;
 import com.android.systemui.statusbar.CommandQueue;
 import com.android.systemui.statusbar.DisableFlagsLogger;
-import com.android.systemui.statusbar.SysuiStatusBarStateController;
 import com.android.systemui.statusbar.VibratorHelper;
 import com.android.systemui.statusbar.notification.stack.NotificationStackScrollLayoutController;
 import com.android.systemui.statusbar.phone.dagger.CentralSurfacesComponent;
@@ -91,19 +89,16 @@ public class CentralSurfacesCommandQueueCallbacks implements CommandQueue.Callba
     private final StatusBarKeyguardViewManager mStatusBarKeyguardViewManager;
     private final AssistManager mAssistManager;
     private final DozeServiceHost mDozeServiceHost;
-    private final SysuiStatusBarStateController mStatusBarStateController;
-    private final NotificationShadeWindowView mNotificationShadeWindowView;
     private final NotificationStackScrollLayoutController mNotificationStackScrollLayoutController;
     private final StatusBarHideIconsForBouncerManager mStatusBarHideIconsForBouncerManager;
     private final PowerManager mPowerManager;
     private final VibratorHelper mVibratorHelper;
     private final Optional<Vibrator> mVibratorOptional;
-    private final LightBarController mLightBarController;
     private final DisableFlagsLogger mDisableFlagsLogger;
     private final int mDisplayId;
     private final boolean mVibrateOnOpening;
     private final VibrationEffect mCameraLaunchGestureVibrationEffect;
-
+    private final SystemBarAttributesListener mSystemBarAttributesListener;
 
     private static final VibrationAttributes HARDWARE_FEEDBACK_VIBRATION_ATTRIBUTES =
             VibrationAttributes.createForUsage(VibrationAttributes.USAGE_HARDWARE_FEEDBACK);
@@ -126,16 +121,14 @@ public class CentralSurfacesCommandQueueCallbacks implements CommandQueue.Callba
             StatusBarKeyguardViewManager statusBarKeyguardViewManager,
             AssistManager assistManager,
             DozeServiceHost dozeServiceHost,
-            SysuiStatusBarStateController statusBarStateController,
-            NotificationShadeWindowView notificationShadeWindowView,
             NotificationStackScrollLayoutController notificationStackScrollLayoutController,
             StatusBarHideIconsForBouncerManager statusBarHideIconsForBouncerManager,
             PowerManager powerManager,
             VibratorHelper vibratorHelper,
             Optional<Vibrator> vibratorOptional,
-            LightBarController lightBarController,
             DisableFlagsLogger disableFlagsLogger,
-            @DisplayId int displayId) {
+            @DisplayId int displayId,
+            SystemBarAttributesListener systemBarAttributesListener) {
 
         mCentralSurfaces = centralSurfaces;
         mContext = context;
@@ -152,20 +145,18 @@ public class CentralSurfacesCommandQueueCallbacks implements CommandQueue.Callba
         mStatusBarKeyguardViewManager = statusBarKeyguardViewManager;
         mAssistManager = assistManager;
         mDozeServiceHost = dozeServiceHost;
-        mStatusBarStateController = statusBarStateController;
-        mNotificationShadeWindowView = notificationShadeWindowView;
         mNotificationStackScrollLayoutController = notificationStackScrollLayoutController;
         mStatusBarHideIconsForBouncerManager = statusBarHideIconsForBouncerManager;
         mPowerManager = powerManager;
         mVibratorHelper = vibratorHelper;
         mVibratorOptional = vibratorOptional;
-        mLightBarController = lightBarController;
         mDisableFlagsLogger = disableFlagsLogger;
         mDisplayId = displayId;
 
         mVibrateOnOpening = resources.getBoolean(R.bool.config_vibrateOnIconAnimation);
         mCameraLaunchGestureVibrationEffect = getCameraGestureVibrationEffect(
                 mVibratorOptional, resources);
+        mSystemBarAttributesListener = systemBarAttributesListener;
     }
 
     @Override
@@ -472,14 +463,18 @@ public class CentralSurfacesCommandQueueCallbacks implements CommandQueue.Callba
         if (displayId != mDisplayId) {
             return;
         }
-        boolean barModeChanged = mCentralSurfaces.setAppearance(appearance);
-
-        mLightBarController.onStatusBarAppearanceChanged(appearanceRegions, barModeChanged,
-                mCentralSurfaces.getBarMode(), navbarColorManagedByIme);
-
-        mCentralSurfaces.updateBubblesVisibility();
-        mStatusBarStateController.setSystemBarAttributes(
-                appearance, behavior, requestedVisibilities, packageName);
+        // SystemBarAttributesListener should __always__ be the top-level listener for system bar
+        // attributes changed.
+        mSystemBarAttributesListener.onSystemBarAttributesChanged(
+                displayId,
+                appearance,
+                appearanceRegions,
+                navbarColorManagedByIme,
+                behavior,
+                requestedVisibilities,
+                packageName,
+                letterboxDetails
+        );
     }
 
     @Override
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/SystemBarAttributesListener.kt b/packages/SystemUI/src/com/android/systemui/statusbar/phone/SystemBarAttributesListener.kt
new file mode 100644
index 000000000000..a0415f2f3d7c
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/SystemBarAttributesListener.kt
@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.statusbar.phone
+
+import android.view.InsetsVisibilities
+import android.view.WindowInsetsController.Appearance
+import android.view.WindowInsetsController.Behavior
+import com.android.internal.statusbar.LetterboxDetails
+import com.android.internal.view.AppearanceRegion
+import com.android.systemui.dump.DumpManager
+import com.android.systemui.flags.FeatureFlags
+import com.android.systemui.flags.Flags
+import com.android.systemui.statusbar.SysuiStatusBarStateController
+import com.android.systemui.statusbar.phone.dagger.CentralSurfacesComponent
+import com.android.systemui.statusbar.phone.dagger.CentralSurfacesComponent.CentralSurfacesScope
+import java.io.PrintWriter
+import javax.inject.Inject
+
+/**
+ * Top-level listener of system attributes changed. This class is __always the first__ one to be
+ * notified about changes.
+ *
+ * It is responsible for modifying any attributes if necessary, and then notifying the other
+ * downstream listeners.
+ */
+@CentralSurfacesScope
+class SystemBarAttributesListener
+@Inject
+internal constructor(
+    private val centralSurfaces: CentralSurfaces,
+    private val featureFlags: FeatureFlags,
+    private val letterboxAppearanceCalculator: LetterboxAppearanceCalculator,
+    private val statusBarStateController: SysuiStatusBarStateController,
+    private val lightBarController: LightBarController,
+    private val dumpManager: DumpManager,
+) : CentralSurfacesComponent.Startable, StatusBarBoundsProvider.BoundsChangeListener {
+
+    private var lastLetterboxAppearance: LetterboxAppearance? = null
+    private var lastSystemBarAttributesParams: SystemBarAttributesParams? = null
+
+    override fun start() {
+        dumpManager.registerDumpable(javaClass.simpleName, this::dump)
+    }
+
+    override fun stop() {
+        dumpManager.unregisterDumpable(javaClass.simpleName)
+    }
+
+    override fun onStatusBarBoundsChanged() {
+        val params = lastSystemBarAttributesParams
+        if (params != null && shouldUseLetterboxAppearance(params.letterboxesArray)) {
+            onSystemBarAttributesChanged(
+                params.displayId,
+                params.appearance,
+                params.appearanceRegionsArray,
+                params.navbarColorManagedByIme,
+                params.behavior,
+                params.requestedVisibilities,
+                params.packageName,
+                params.letterboxesArray)
+        }
+    }
+
+    fun onSystemBarAttributesChanged(
+        displayId: Int,
+        @Appearance originalAppearance: Int,
+        originalAppearanceRegions: Array<AppearanceRegion>,
+        navbarColorManagedByIme: Boolean,
+        @Behavior behavior: Int,
+        requestedVisibilities: InsetsVisibilities,
+        packageName: String,
+        letterboxDetails: Array<LetterboxDetails>
+    ) {
+        lastSystemBarAttributesParams =
+            SystemBarAttributesParams(
+                displayId,
+                originalAppearance,
+                originalAppearanceRegions.toList(),
+                navbarColorManagedByIme,
+                behavior,
+                requestedVisibilities,
+                packageName,
+                letterboxDetails.toList())
+
+        val (appearance, appearanceRegions) =
+            modifyAppearanceIfNeeded(
+                originalAppearance, originalAppearanceRegions, letterboxDetails)
+
+        val barModeChanged = centralSurfaces.setAppearance(appearance)
+
+        lightBarController.onStatusBarAppearanceChanged(
+            appearanceRegions, barModeChanged, centralSurfaces.barMode, navbarColorManagedByIme)
+
+        centralSurfaces.updateBubblesVisibility()
+        statusBarStateController.setSystemBarAttributes(
+            appearance, behavior, requestedVisibilities, packageName)
+    }
+
+    private fun modifyAppearanceIfNeeded(
+        appearance: Int,
+        appearanceRegions: Array<AppearanceRegion>,
+        letterboxDetails: Array<LetterboxDetails>
+    ): Pair<Int, Array<AppearanceRegion>> =
+        if (shouldUseLetterboxAppearance(letterboxDetails)) {
+            val letterboxAppearance =
+                letterboxAppearanceCalculator.getLetterboxAppearance(
+                    appearance, appearanceRegions, letterboxDetails)
+            lastLetterboxAppearance = letterboxAppearance
+            Pair(letterboxAppearance.appearance, letterboxAppearance.appearanceRegions)
+        } else {
+            lastLetterboxAppearance = null
+            Pair(appearance, appearanceRegions)
+        }
+
+    private fun shouldUseLetterboxAppearance(letterboxDetails: Array<LetterboxDetails>) =
+        isLetterboxAppearanceFlagEnabled() && letterboxDetails.isNotEmpty()
+
+    private fun isLetterboxAppearanceFlagEnabled() =
+        featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)
+
+    private fun dump(printWriter: PrintWriter, strings: Array<String>) {
+        printWriter.println("lastSystemBarAttributesParams: $lastSystemBarAttributesParams")
+        printWriter.println("lastLetterboxAppearance: $lastLetterboxAppearance")
+        printWriter.println("letterbox appearance flag: ${isLetterboxAppearanceFlagEnabled()}")
+    }
+}
+
+/**
+ * Keeps track of the parameters passed in
+ * [SystemBarAttributesListener.onSystemBarAttributesChanged].
+ */
+private data class SystemBarAttributesParams(
+    val displayId: Int,
+    @Appearance val appearance: Int,
+    val appearanceRegions: List<AppearanceRegion>,
+    val navbarColorManagedByIme: Boolean,
+    @Behavior val behavior: Int,
+    val requestedVisibilities: InsetsVisibilities,
+    val packageName: String,
+    val letterboxes: List<LetterboxDetails>,
+) {
+    val letterboxesArray = letterboxes.toTypedArray()
+    val appearanceRegionsArray = appearanceRegions.toTypedArray()
+}
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/CentralSurfacesStartableModule.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/CentralSurfacesStartableModule.java
index 590522fc8751..d57e6a791489 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/CentralSurfacesStartableModule.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/CentralSurfacesStartableModule.java
@@ -17,6 +17,7 @@
 package com.android.systemui.statusbar.phone.dagger;
 
 import com.android.systemui.statusbar.phone.LetterboxAppearanceCalculator;
+import com.android.systemui.statusbar.phone.SystemBarAttributesListener;
 
 import java.util.Set;
 
@@ -34,4 +35,9 @@ interface CentralSurfacesStartableModule {
     @IntoSet
     CentralSurfacesComponent.Startable letterboxAppearanceCalculator(
             LetterboxAppearanceCalculator letterboxAppearanceCalculator);
+
+    @Binds
+    @IntoSet
+    CentralSurfacesComponent.Startable sysBarAttrsListener(
+            SystemBarAttributesListener systemBarAttributesListener);
 }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java
index b3bef07cb820..c4e7a8a2c17b 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java
@@ -53,10 +53,12 @@ import com.android.systemui.statusbar.notification.stack.NotificationStackScroll
 import com.android.systemui.statusbar.phone.KeyguardBottomAreaView;
 import com.android.systemui.statusbar.phone.LetterboxAppearanceCalculator;
 import com.android.systemui.statusbar.phone.NotificationIconAreaController;
+import com.android.systemui.statusbar.phone.StatusBarBoundsProvider;
 import com.android.systemui.statusbar.phone.StatusBarHideIconsForBouncerManager;
 import com.android.systemui.statusbar.phone.StatusBarIconController;
 import com.android.systemui.statusbar.phone.StatusBarLocationPublisher;
 import com.android.systemui.statusbar.phone.StatusIconContainer;
+import com.android.systemui.statusbar.phone.SystemBarAttributesListener;
 import com.android.systemui.statusbar.phone.TapAgainView;
 import com.android.systemui.statusbar.phone.fragment.CollapsedStatusBarFragment;
 import com.android.systemui.statusbar.phone.fragment.CollapsedStatusBarFragmentLogger;
@@ -258,6 +260,11 @@ public abstract class StatusBarViewModule {
             LetterboxAppearanceCalculator letterboxAppearanceCalculator
     );
 
+    @Binds
+    @IntoSet
+    abstract StatusBarBoundsProvider.BoundsChangeListener sysBarAttrsListenerAsBoundsListener(
+            SystemBarAttributesListener systemBarAttributesListener);
+
     /**
      * Creates a new {@link CollapsedStatusBarFragment}.
      *
diff --git a/packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacksTest.java b/packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacksTest.java
index d79f3361408b..7b7a48be5b17 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacksTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/CentralSurfacesCommandQueueCallbacksTest.java
@@ -22,26 +22,28 @@ import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyZeroInteractions;
 import static org.mockito.Mockito.when;
 
 import android.app.StatusBarManager;
 import android.os.PowerManager;
 import android.os.Vibrator;
 import android.testing.AndroidTestingRunner;
+import android.view.InsetsVisibilities;
 
 import androidx.test.filters.SmallTest;
 
 import com.android.internal.logging.MetricsLogger;
 import com.android.internal.logging.testing.FakeMetricsLogger;
+import com.android.internal.statusbar.LetterboxDetails;
+import com.android.internal.view.AppearanceRegion;
 import com.android.keyguard.KeyguardUpdateMonitor;
 import com.android.systemui.SysuiTestCase;
 import com.android.systemui.assist.AssistManager;
 import com.android.systemui.keyguard.WakefulnessLifecycle;
 import com.android.systemui.shade.NotificationPanelViewController;
-import com.android.systemui.shade.NotificationShadeWindowView;
 import com.android.systemui.statusbar.CommandQueue;
 import com.android.systemui.statusbar.DisableFlagsLogger;
-import com.android.systemui.statusbar.StatusBarStateControllerImpl;
 import com.android.systemui.statusbar.VibratorHelper;
 import com.android.systemui.statusbar.notification.stack.NotificationStackScrollLayoutController;
 import com.android.systemui.statusbar.policy.DeviceProvisionedController;
@@ -60,6 +62,7 @@ import java.util.Optional;
 @SmallTest
 @RunWith(AndroidTestingRunner.class)
 public class CentralSurfacesCommandQueueCallbacksTest extends SysuiTestCase {
+
     @Mock private CentralSurfaces mCentralSurfaces;
     @Mock private ShadeController mShadeController;
     @Mock private CommandQueue mCommandQueue;
@@ -74,14 +77,12 @@ public class CentralSurfacesCommandQueueCallbacksTest extends SysuiTestCase {
     @Mock private StatusBarKeyguardViewManager mStatusBarKeyguardViewManager;
     @Mock private AssistManager mAssistManager;
     @Mock private DozeServiceHost mDozeServiceHost;
-    @Mock private StatusBarStateControllerImpl mStatusBarStateController;
-    @Mock private NotificationShadeWindowView mNotificationShadeWindowView;
     @Mock private NotificationStackScrollLayoutController mNotificationStackScrollLayoutController;
     @Mock private PowerManager mPowerManager;
     @Mock private VibratorHelper mVibratorHelper;
     @Mock private Vibrator mVibrator;
-    @Mock private LightBarController mLightBarController;
     @Mock private StatusBarHideIconsForBouncerManager mStatusBarHideIconsForBouncerManager;
+    @Mock private SystemBarAttributesListener mSystemBarAttributesListener;
 
     CentralSurfacesCommandQueueCallbacks mSbcqCallbacks;
 
@@ -106,16 +107,14 @@ public class CentralSurfacesCommandQueueCallbacksTest extends SysuiTestCase {
                 mStatusBarKeyguardViewManager,
                 mAssistManager,
                 mDozeServiceHost,
-                mStatusBarStateController,
-                mNotificationShadeWindowView,
                 mNotificationStackScrollLayoutController,
                 mStatusBarHideIconsForBouncerManager,
                 mPowerManager,
                 mVibratorHelper,
                 Optional.of(mVibrator),
-                mLightBarController,
                 new DisableFlagsLogger(),
-                DEFAULT_DISPLAY);
+                DEFAULT_DISPLAY,
+                mSystemBarAttributesListener);
 
         when(mDeviceProvisionedController.isCurrentUserSetup()).thenReturn(true);
         when(mRemoteInputQuickSettingsDisabler.adjustDisableFlags(anyInt()))
@@ -170,5 +169,59 @@ public class CentralSurfacesCommandQueueCallbacksTest extends SysuiTestCase {
         verify(mDozeServiceHost).setAlwaysOnSuppressed(false);
     }
 
+    @Test
+    public void onSystemBarAttributesChanged_forwardsToSysBarAttrsListener() {
+        int displayId = DEFAULT_DISPLAY;
+        int appearance = 123;
+        AppearanceRegion[] appearanceRegions = new AppearanceRegion[]{};
+        boolean navbarColorManagedByIme = true;
+        int behavior = 456;
+        InsetsVisibilities requestedVisibilities = new InsetsVisibilities();
+        String packageName = "test package name";
+        LetterboxDetails[] letterboxDetails = new LetterboxDetails[]{};
+
+        mSbcqCallbacks.onSystemBarAttributesChanged(
+                displayId,
+                appearance,
+                appearanceRegions,
+                navbarColorManagedByIme,
+                behavior,
+                requestedVisibilities,
+                packageName,
+                letterboxDetails);
+
+        verify(mSystemBarAttributesListener).onSystemBarAttributesChanged(
+                displayId,
+                appearance,
+                appearanceRegions,
+                navbarColorManagedByIme,
+                behavior,
+                requestedVisibilities,
+                packageName,
+                letterboxDetails
+        );
+    }
 
+    @Test
+    public void onSystemBarAttributesChanged_differentDisplayId_doesNotForwardToAttrsListener() {
+        int appearance = 123;
+        AppearanceRegion[] appearanceRegions = new AppearanceRegion[]{};
+        boolean navbarColorManagedByIme = true;
+        int behavior = 456;
+        InsetsVisibilities requestedVisibilities = new InsetsVisibilities();
+        String packageName = "test package name";
+        LetterboxDetails[] letterboxDetails = new LetterboxDetails[]{};
+
+        mSbcqCallbacks.onSystemBarAttributesChanged(
+                DEFAULT_DISPLAY + 1,
+                appearance,
+                appearanceRegions,
+                navbarColorManagedByIme,
+                behavior,
+                requestedVisibilities,
+                packageName,
+                letterboxDetails);
+
+        verifyZeroInteractions(mSystemBarAttributesListener);
+    }
 }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/SystemBarAttributesListenerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/SystemBarAttributesListenerTest.kt
new file mode 100644
index 000000000000..fa7b2599c108
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/statusbar/phone/SystemBarAttributesListenerTest.kt
@@ -0,0 +1,250 @@
+package com.android.systemui.statusbar.phone
+
+import android.graphics.Rect
+import android.testing.AndroidTestingRunner
+import android.view.Display
+import android.view.InsetsVisibilities
+import android.view.WindowInsetsController
+import android.view.WindowInsetsController.APPEARANCE_LIGHT_NAVIGATION_BARS
+import android.view.WindowInsetsController.APPEARANCE_LIGHT_STATUS_BARS
+import android.view.WindowInsetsController.APPEARANCE_LOW_PROFILE_BARS
+import android.view.WindowInsetsController.Appearance
+import androidx.test.filters.SmallTest
+import com.android.internal.statusbar.LetterboxDetails
+import com.android.internal.view.AppearanceRegion
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.dump.DumpManager
+import com.android.systemui.flags.FeatureFlags
+import com.android.systemui.flags.Flags
+import com.android.systemui.statusbar.SysuiStatusBarStateController
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.ArgumentMatchers.any
+import org.mockito.ArgumentMatchers.anyBoolean
+import org.mockito.ArgumentMatchers.anyInt
+import org.mockito.ArgumentMatchers.eq
+import org.mockito.Mock
+import org.mockito.Mockito
+import org.mockito.Mockito.reset
+import org.mockito.Mockito.verify
+import org.mockito.Mockito.verifyZeroInteractions
+import org.mockito.Mockito.`when` as whenever
+import org.mockito.MockitoAnnotations
+
+@SmallTest
+@RunWith(AndroidTestingRunner::class)
+class SystemBarAttributesListenerTest : SysuiTestCase() {
+
+    @Mock private lateinit var dumpManager: DumpManager
+    @Mock private lateinit var lightBarController: LightBarController
+    @Mock private lateinit var statusBarStateController: SysuiStatusBarStateController
+    @Mock private lateinit var letterboxAppearanceCalculator: LetterboxAppearanceCalculator
+    @Mock private lateinit var featureFlags: FeatureFlags
+    @Mock private lateinit var centralSurfaces: CentralSurfaces
+
+    private lateinit var sysBarAttrsListener: SystemBarAttributesListener
+
+    @Before
+    fun setUp() {
+        MockitoAnnotations.initMocks(this)
+
+        whenever(
+                letterboxAppearanceCalculator.getLetterboxAppearance(
+                    anyInt(), anyObject(), anyObject()))
+            .thenReturn(TEST_LETTERBOX_APPEARANCE)
+
+        sysBarAttrsListener =
+            SystemBarAttributesListener(
+                centralSurfaces,
+                featureFlags,
+                letterboxAppearanceCalculator,
+                statusBarStateController,
+                lightBarController,
+                dumpManager)
+    }
+
+    @Test
+    fun onSysBarAttrsChanged_forwardsAppearanceToCentralSurfaces() {
+        val appearance = APPEARANCE_LIGHT_STATUS_BARS or APPEARANCE_LIGHT_NAVIGATION_BARS
+
+        changeSysBarAttrs(appearance)
+
+        verify(centralSurfaces).setAppearance(appearance)
+    }
+
+    @Test
+    fun onSysBarAttrsChanged_flagTrue_forwardsLetterboxAppearanceToCentralSurfaces() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_LETTERBOX_DETAILS)
+
+        verify(centralSurfaces).setAppearance(TEST_LETTERBOX_APPEARANCE.appearance)
+    }
+
+    @Test
+    fun onSysBarAttrsChanged_flagTrue_noLetterbox_forwardsOriginalAppearanceToCtrlSrfcs() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+
+        changeSysBarAttrs(TEST_APPEARANCE, arrayOf<LetterboxDetails>())
+
+        verify(centralSurfaces).setAppearance(TEST_APPEARANCE)
+    }
+
+    @Test
+    fun onSysBarAttrsChanged_forwardsAppearanceToStatusBarStateController() {
+        changeSysBarAttrs(TEST_APPEARANCE)
+
+        verify(statusBarStateController)
+            .setSystemBarAttributes(eq(TEST_APPEARANCE), anyInt(), any(), any())
+    }
+
+    @Test
+    fun onSysBarAttrsChanged_flagTrue_forwardsLetterboxAppearanceToStatusBarStateCtrl() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_LETTERBOX_DETAILS)
+
+        verify(statusBarStateController)
+            .setSystemBarAttributes(
+                eq(TEST_LETTERBOX_APPEARANCE.appearance), anyInt(), any(), any())
+    }
+
+    @Test
+    fun onSysBarAttrsChanged_forwardsAppearanceToLightBarController() {
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_APPEARANCE_REGIONS)
+
+        verify(lightBarController)
+            .onStatusBarAppearanceChanged(
+                eq(TEST_APPEARANCE_REGIONS), anyBoolean(), anyInt(), anyBoolean())
+    }
+
+    @Test
+    fun onSysBarAttrsChanged_flagTrue_forwardsLetterboxAppearanceToLightBarController() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_APPEARANCE_REGIONS, TEST_LETTERBOX_DETAILS)
+
+        verify(lightBarController)
+            .onStatusBarAppearanceChanged(
+                eq(TEST_LETTERBOX_APPEARANCE.appearanceRegions),
+                anyBoolean(),
+                anyInt(),
+                anyBoolean())
+    }
+
+    @Test
+    fun onStatusBarBoundsChanged_forwardsLetterboxAppearanceToStatusBarStateController() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_APPEARANCE_REGIONS, TEST_LETTERBOX_DETAILS)
+        reset(centralSurfaces, lightBarController, statusBarStateController)
+
+        sysBarAttrsListener.onStatusBarBoundsChanged()
+
+        verify(statusBarStateController)
+            .setSystemBarAttributes(
+                eq(TEST_LETTERBOX_APPEARANCE.appearance), anyInt(), any(), any())
+    }
+
+    @Test
+    fun onStatusBarBoundsChanged_forwardsLetterboxAppearanceToLightBarController() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_APPEARANCE_REGIONS, TEST_LETTERBOX_DETAILS)
+        reset(centralSurfaces, lightBarController, statusBarStateController)
+
+        sysBarAttrsListener.onStatusBarBoundsChanged()
+
+        verify(lightBarController)
+            .onStatusBarAppearanceChanged(
+                eq(TEST_LETTERBOX_APPEARANCE.appearanceRegions),
+                anyBoolean(),
+                anyInt(),
+                anyBoolean())
+    }
+
+    @Test
+    fun onStatusBarBoundsChanged_forwardsLetterboxAppearanceToCentralSurfaces() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_APPEARANCE_REGIONS, TEST_LETTERBOX_DETAILS)
+        reset(centralSurfaces, lightBarController, statusBarStateController)
+
+        sysBarAttrsListener.onStatusBarBoundsChanged()
+
+        verify(centralSurfaces).setAppearance(TEST_LETTERBOX_APPEARANCE.appearance)
+    }
+
+    @Test
+    fun onStatusBarBoundsChanged_previousCallEmptyLetterbox_doesNothing() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(true)
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_APPEARANCE_REGIONS, arrayOf())
+        reset(centralSurfaces, lightBarController, statusBarStateController)
+
+        sysBarAttrsListener.onStatusBarBoundsChanged()
+
+        verifyZeroInteractions(centralSurfaces, lightBarController, statusBarStateController)
+    }
+
+    @Test
+    fun onStatusBarBoundsChanged_flagFalse_doesNothing() {
+        whenever(featureFlags.isEnabled(Flags.STATUS_BAR_LETTERBOX_APPEARANCE)).thenReturn(false)
+        changeSysBarAttrs(TEST_APPEARANCE, TEST_APPEARANCE_REGIONS, TEST_LETTERBOX_DETAILS)
+        reset(centralSurfaces, lightBarController, statusBarStateController)
+
+        sysBarAttrsListener.onStatusBarBoundsChanged()
+
+        verifyZeroInteractions(centralSurfaces, lightBarController, statusBarStateController)
+    }
+
+    private fun changeSysBarAttrs(@Appearance appearance: Int) {
+        changeSysBarAttrs(appearance, arrayOf<LetterboxDetails>())
+    }
+
+    private fun changeSysBarAttrs(
+        @Appearance appearance: Int,
+        letterboxDetails: Array<LetterboxDetails>
+    ) {
+        changeSysBarAttrs(appearance, arrayOf(), letterboxDetails)
+    }
+
+    private fun changeSysBarAttrs(
+        @Appearance appearance: Int,
+        appearanceRegions: Array<AppearanceRegion>
+    ) {
+        changeSysBarAttrs(appearance, appearanceRegions, arrayOf())
+    }
+
+    private fun changeSysBarAttrs(
+        @Appearance appearance: Int,
+        appearanceRegions: Array<AppearanceRegion>,
+        letterboxDetails: Array<LetterboxDetails>
+    ) {
+        sysBarAttrsListener.onSystemBarAttributesChanged(
+            Display.DEFAULT_DISPLAY,
+            appearance,
+            appearanceRegions,
+            /* navbarColorManagedByIme= */ false,
+            WindowInsetsController.BEHAVIOR_DEFAULT,
+            InsetsVisibilities(),
+            "package name",
+            letterboxDetails)
+    }
+
+    companion object {
+        private const val TEST_APPEARANCE =
+            APPEARANCE_LIGHT_STATUS_BARS or APPEARANCE_LIGHT_NAVIGATION_BARS
+        private val TEST_APPEARANCE_REGION = AppearanceRegion(TEST_APPEARANCE, Rect(0, 0, 150, 300))
+        private val TEST_APPEARANCE_REGIONS = arrayOf(TEST_APPEARANCE_REGION)
+        private val TEST_LETTERBOX_DETAILS =
+            arrayOf(
+                LetterboxDetails(
+                    /* letterboxInnerBounds= */ Rect(0, 0, 0, 0),
+                    /* letterboxFullBounds= */ Rect(0, 0, 0, 0),
+                    /* appAppearance= */ 0))
+        private val TEST_LETTERBOX_APPEARANCE =
+            LetterboxAppearance(/* appearance= */ APPEARANCE_LOW_PROFILE_BARS, arrayOf())
+    }
+}
+
+private fun <T> anyObject(): T {
+    return Mockito.anyObject<T>()
+}
diff --git a/services/core/java/com/android/server/statusbar/StatusBarManagerService.java b/services/core/java/com/android/server/statusbar/StatusBarManagerService.java
index 71b1bc2e24bc..bec3754536e2 100644
--- a/services/core/java/com/android/server/statusbar/StatusBarManagerService.java
+++ b/services/core/java/com/android/server/statusbar/StatusBarManagerService.java
@@ -1207,7 +1207,7 @@ public class StatusBarManagerService extends IStatusBarService.Stub implements D
         private int mImeBackDisposition = 0;
         private boolean mShowImeSwitcher = false;
         private IBinder mImeToken = null;
-        private LetterboxDetails[] mLetterboxDetails;
+        private LetterboxDetails[] mLetterboxDetails = new LetterboxDetails[0];
 
         private void setBarAttributes(@Appearance int appearance,
                 AppearanceRegion[] appearanceRegions, boolean navbarColorManagedByIme,