diff --git a/packages/SystemUI/aconfig/systemui.aconfig b/packages/SystemUI/aconfig/systemui.aconfig
index a745ab5..5202c49 100644
--- a/packages/SystemUI/aconfig/systemui.aconfig
+++ b/packages/SystemUI/aconfig/systemui.aconfig
@@ -114,6 +114,13 @@
 }
 
 flag {
+    name: "unfold_animation_background_progress"
+    namespace: "systemui"
+    description: "Moves unfold animation progress calculation to a background thread"
+    bug: "277879146"
+}
+
+flag {
     name: "qs_new_pipeline"
     namespace: "systemui"
     description: "Use the new pipeline for Quick Settings. Should have no behavior changes."
diff --git a/packages/SystemUI/shared/src/com/android/systemui/unfold/system/ActivityManagerActivityTypeProvider.kt b/packages/SystemUI/shared/src/com/android/systemui/unfold/system/ActivityManagerActivityTypeProvider.kt
index c9e57b4..b33f6fa 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/unfold/system/ActivityManagerActivityTypeProvider.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/unfold/system/ActivityManagerActivityTypeProvider.kt
@@ -32,8 +32,7 @@
     override val isHomeActivity: Boolean?
         get() = _isHomeActivity
 
-    private var _isHomeActivity: Boolean? = null
-
+    @Volatile private var _isHomeActivity: Boolean? = null
 
     override fun init() {
         _isHomeActivity = activityManager.isOnHomeActivity()
diff --git a/packages/SystemUI/shared/src/com/android/systemui/unfold/system/DeviceStateManagerFoldProvider.kt b/packages/SystemUI/shared/src/com/android/systemui/unfold/system/DeviceStateManagerFoldProvider.kt
index 3b8d318..baa8889 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/unfold/system/DeviceStateManagerFoldProvider.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/unfold/system/DeviceStateManagerFoldProvider.kt
@@ -18,18 +18,19 @@
 import android.hardware.devicestate.DeviceStateManager
 import com.android.systemui.unfold.updates.FoldProvider
 import com.android.systemui.unfold.updates.FoldProvider.FoldCallback
+import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.Executor
 import javax.inject.Inject
 import javax.inject.Singleton
 
 @Singleton
-class DeviceStateManagerFoldProvider @Inject constructor(
-    private val deviceStateManager: DeviceStateManager,
-    private val context: Context
-) : FoldProvider {
+class DeviceStateManagerFoldProvider
+@Inject
+constructor(private val deviceStateManager: DeviceStateManager, private val context: Context) :
+    FoldProvider {
 
-    private val callbacks: MutableMap<FoldCallback,
-            DeviceStateManager.DeviceStateCallback> = hashMapOf()
+    private val callbacks =
+        ConcurrentHashMap<FoldCallback, DeviceStateManager.DeviceStateCallback>()
 
     override fun registerCallback(callback: FoldCallback, executor: Executor) {
         val listener = FoldStateListener(context, callback)
@@ -39,13 +40,9 @@
 
     override fun unregisterCallback(callback: FoldCallback) {
         val listener = callbacks.remove(callback)
-        listener?.let {
-            deviceStateManager.unregisterCallback(it)
-        }
+        listener?.let { deviceStateManager.unregisterCallback(it) }
     }
 
-    private inner class FoldStateListener(
-        context: Context,
-        listener: FoldCallback
-    ) : DeviceStateManager.FoldStateListener(context, { listener.onFoldUpdated(it) })
+    private inner class FoldStateListener(context: Context, listener: FoldCallback) :
+        DeviceStateManager.FoldStateListener(context, { listener.onFoldUpdated(it) })
 }
diff --git a/packages/SystemUI/shared/src/com/android/systemui/unfold/system/SystemUnfoldSharedModule.kt b/packages/SystemUI/shared/src/com/android/systemui/unfold/system/SystemUnfoldSharedModule.kt
index 7b67e3f..7af9917 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/unfold/system/SystemUnfoldSharedModule.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/unfold/system/SystemUnfoldSharedModule.kt
@@ -15,24 +15,29 @@
 package com.android.systemui.unfold.system
 
 import android.os.Handler
+import android.os.HandlerThread
+import android.os.Looper
+import android.os.Process
 import com.android.systemui.dagger.qualifiers.Main
 import com.android.systemui.dagger.qualifiers.UiBackground
 import com.android.systemui.unfold.config.ResourceUnfoldTransitionConfig
 import com.android.systemui.unfold.config.UnfoldTransitionConfig
-import com.android.systemui.unfold.dagger.UnfoldSingleThreadBg
+import com.android.systemui.unfold.dagger.UnfoldBg
 import com.android.systemui.unfold.dagger.UnfoldMain
+import com.android.systemui.unfold.dagger.UnfoldSingleThreadBg
 import com.android.systemui.unfold.updates.FoldProvider
 import com.android.systemui.unfold.util.CurrentActivityTypeProvider
 import dagger.Binds
 import dagger.Module
+import dagger.Provides
 import java.util.concurrent.Executor
+import javax.inject.Singleton
 
 /**
- * Dagger module with system-only dependencies for the unfold animation.
- * The code that is used to calculate unfold transition progress
- * depends on some hidden APIs that are not available in normal
- * apps. In order to re-use this code and use alternative implementations
- * of these classes in other apps and hidden APIs here.
+ * Dagger module with system-only dependencies for the unfold animation. The code that is used to
+ * calculate unfold transition progress depends on some hidden APIs that are not available in normal
+ * apps. In order to re-use this code and use alternative implementations of these classes in other
+ * apps and hidden APIs here.
  */
 @Module
 abstract class SystemUnfoldSharedModule {
@@ -61,4 +66,22 @@
     @Binds
     @UnfoldSingleThreadBg
     abstract fun backgroundExecutor(@UiBackground executor: Executor): Executor
+
+    companion object {
+        @Provides
+        @UnfoldBg
+        @Singleton
+        fun unfoldBgProgressHandler(@UnfoldBg looper: Looper): Handler {
+            return Handler(looper)
+        }
+
+        @Provides
+        @UnfoldBg
+        @Singleton
+        fun provideBgLooper(): Looper {
+            return HandlerThread("UnfoldBg", Process.THREAD_PRIORITY_FOREGROUND)
+                .apply { start() }
+                .looper
+        }
+    }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/dagger/SysUIComponent.java b/packages/SystemUI/src/com/android/systemui/dagger/SysUIComponent.java
index d9e0629..e7b8773 100644
--- a/packages/SystemUI/src/com/android/systemui/dagger/SysUIComponent.java
+++ b/packages/SystemUI/src/com/android/systemui/dagger/SysUIComponent.java
@@ -19,6 +19,7 @@
 import com.android.systemui.BootCompleteCacheImpl;
 import com.android.systemui.CoreStartable;
 import com.android.systemui.Dependency;
+import com.android.systemui.Flags;
 import com.android.systemui.InitController;
 import com.android.systemui.SystemUIAppComponentFactoryBase;
 import com.android.systemui.dagger.qualifiers.PerUser;
@@ -35,6 +36,7 @@
 import com.android.systemui.unfold.FoldStateLoggingProvider;
 import com.android.systemui.unfold.SysUIUnfoldComponent;
 import com.android.systemui.unfold.UnfoldTransitionProgressProvider;
+import com.android.systemui.unfold.dagger.UnfoldBg;
 import com.android.systemui.unfold.progress.UnfoldTransitionProgressForwarder;
 import com.android.wm.shell.back.BackAnimation;
 import com.android.wm.shell.bubbles.Bubbles;
@@ -144,7 +146,15 @@
         getConnectingDisplayViewModel().init();
         getFoldStateLoggingProvider().ifPresent(FoldStateLoggingProvider::init);
         getFoldStateLogger().ifPresent(FoldStateLogger::init);
-        getUnfoldTransitionProgressProvider()
+
+        Optional<UnfoldTransitionProgressProvider> unfoldTransitionProgressProvider;
+
+        if (Flags.unfoldAnimationBackgroundProgress()) {
+            unfoldTransitionProgressProvider = getBgUnfoldTransitionProgressProvider();
+        } else {
+            unfoldTransitionProgressProvider = getUnfoldTransitionProgressProvider();
+        }
+        unfoldTransitionProgressProvider
                 .ifPresent(
                         (progressProvider) ->
                                 getUnfoldTransitionProgressForwarder()
@@ -170,7 +180,14 @@
     ContextComponentHelper getContextComponentHelper();
 
     /**
-     * Creates a UnfoldTransitionProgressProvider.
+     * Creates a UnfoldTransitionProgressProvider that calculates progress in the background.
+     */
+    @SysUISingleton
+    @UnfoldBg
+    Optional<UnfoldTransitionProgressProvider> getBgUnfoldTransitionProgressProvider();
+
+    /**
+     * Creates a UnfoldTransitionProgressProvider that calculates progress in the main thread.
      */
     @SysUISingleton
     Optional<UnfoldTransitionProgressProvider> getUnfoldTransitionProgressProvider();
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/LifecycleScreenStatusProvider.kt b/packages/SystemUI/src/com/android/systemui/keyguard/LifecycleScreenStatusProvider.kt
index f9b89b1..7354cfc 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/LifecycleScreenStatusProvider.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/LifecycleScreenStatusProvider.kt
@@ -18,6 +18,7 @@
 import com.android.systemui.unfold.updates.screen.ScreenStatusProvider
 import com.android.systemui.unfold.updates.screen.ScreenStatusProvider.ScreenListener
 import com.android.app.tracing.traceSection
+import java.util.concurrent.CopyOnWriteArrayList
 import javax.inject.Inject
 import javax.inject.Singleton
 
@@ -29,7 +30,7 @@
         screenLifecycle.addObserver(this)
     }
 
-    private val listeners: MutableList<ScreenListener> = mutableListOf()
+    private val listeners: MutableList<ScreenListener> = CopyOnWriteArrayList()
 
     override fun removeCallback(listener: ScreenListener) {
         listeners.remove(listener)
diff --git a/packages/SystemUI/src/com/android/systemui/unfold/SysUIUnfoldModule.kt b/packages/SystemUI/src/com/android/systemui/unfold/SysUIUnfoldModule.kt
index 8ae093a..10fc83c 100644
--- a/packages/SystemUI/src/com/android/systemui/unfold/SysUIUnfoldModule.kt
+++ b/packages/SystemUI/src/com/android/systemui/unfold/SysUIUnfoldModule.kt
@@ -20,6 +20,7 @@
 import com.android.systemui.dagger.SysUISingleton
 import com.android.systemui.shade.NotificationPanelUnfoldAnimationController
 import com.android.systemui.statusbar.phone.StatusBarMoveFromCenterAnimationController
+import com.android.systemui.unfold.dagger.UnfoldBg
 import com.android.systemui.unfold.util.NaturalRotationUnfoldProgressProvider
 import com.android.systemui.unfold.util.ScopedUnfoldTransitionProgressProvider
 import com.android.systemui.unfold.util.UnfoldKeyguardVisibilityManager
@@ -33,10 +34,7 @@
 import javax.inject.Named
 import javax.inject.Scope
 
-@Scope
-@MustBeDocumented
-@Retention(AnnotationRetention.RUNTIME)
-annotation class SysUIUnfoldScope
+@Scope @MustBeDocumented @Retention(AnnotationRetention.RUNTIME) annotation class SysUIUnfoldScope
 
 /**
  * Creates an injectable [SysUIUnfoldComponent] that provides objects that have been scoped with
@@ -55,20 +53,21 @@
     @Provides
     @SysUISingleton
     fun provideSysUIUnfoldComponent(
-            provider: Optional<UnfoldTransitionProgressProvider>,
-            rotationProvider: Optional<NaturalRotationUnfoldProgressProvider>,
-            @Named(UNFOLD_STATUS_BAR) scopedProvider:
-            Optional<ScopedUnfoldTransitionProgressProvider>,
-            unfoldLatencyTracker: Lazy<UnfoldLatencyTracker>,
-            factory: SysUIUnfoldComponent.Factory
+        provider: Optional<UnfoldTransitionProgressProvider>,
+        rotationProvider: Optional<NaturalRotationUnfoldProgressProvider>,
+        @Named(UNFOLD_STATUS_BAR) scopedProvider: Optional<ScopedUnfoldTransitionProgressProvider>,
+        @UnfoldBg bgProvider: Optional<UnfoldTransitionProgressProvider>,
+        unfoldLatencyTracker: Lazy<UnfoldLatencyTracker>,
+        factory: SysUIUnfoldComponent.Factory
     ): Optional<SysUIUnfoldComponent> {
         val p1 = provider.getOrNull()
         val p2 = rotationProvider.getOrNull()
         val p3 = scopedProvider.getOrNull()
-        return if (p1 == null || p2 == null || p3 == null) {
+        val p4 = bgProvider.getOrNull()
+        return if (p1 == null || p2 == null || p3 == null || p4 == null) {
             Optional.empty()
         } else {
-            Optional.of(factory.create(p1, p2, p3, unfoldLatencyTracker.get()))
+            Optional.of(factory.create(p1, p2, p3, p4, unfoldLatencyTracker.get()))
         }
     }
 }
@@ -76,13 +75,15 @@
 @SysUIUnfoldScope
 @Subcomponent
 interface SysUIUnfoldComponent {
+
     @Subcomponent.Factory
     interface Factory {
         fun create(
-                @BindsInstance p1: UnfoldTransitionProgressProvider,
-                @BindsInstance p2: NaturalRotationUnfoldProgressProvider,
-                @BindsInstance p3: ScopedUnfoldTransitionProgressProvider,
-                @BindsInstance p4: UnfoldLatencyTracker,
+            @BindsInstance p1: UnfoldTransitionProgressProvider,
+            @BindsInstance p2: NaturalRotationUnfoldProgressProvider,
+            @BindsInstance p3: ScopedUnfoldTransitionProgressProvider,
+            @BindsInstance @UnfoldBg p4: UnfoldTransitionProgressProvider,
+            @BindsInstance p5: UnfoldLatencyTracker,
         ): SysUIUnfoldComponent
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/unfold/UnfoldLightRevealOverlayAnimation.kt b/packages/SystemUI/src/com/android/systemui/unfold/UnfoldLightRevealOverlayAnimation.kt
index 36a1e8a..b72c6f1 100644
--- a/packages/SystemUI/src/com/android/systemui/unfold/UnfoldLightRevealOverlayAnimation.kt
+++ b/packages/SystemUI/src/com/android/systemui/unfold/UnfoldLightRevealOverlayAnimation.kt
@@ -35,6 +35,9 @@
 import android.view.SurfaceSession
 import android.view.WindowManager
 import android.view.WindowlessWindowManager
+import com.android.app.tracing.traceSection
+import com.android.keyguard.logging.ScrimLogger
+import com.android.systemui.Flags.unfoldAnimationBackgroundProgress
 import com.android.systemui.dagger.qualifiers.Main
 import com.android.systemui.flags.FeatureFlags
 import com.android.systemui.flags.Flags
@@ -45,16 +48,16 @@
 import com.android.systemui.unfold.UnfoldLightRevealOverlayAnimation.AddOverlayReason.FOLD
 import com.android.systemui.unfold.UnfoldLightRevealOverlayAnimation.AddOverlayReason.UNFOLD
 import com.android.systemui.unfold.UnfoldTransitionProgressProvider.TransitionProgressListener
+import com.android.systemui.unfold.dagger.UnfoldBg
 import com.android.systemui.unfold.updates.RotationChangeProvider
 import com.android.systemui.unfold.util.ScaleAwareTransitionProgressProvider.Companion.areAnimationsEnabled
 import com.android.systemui.util.concurrency.ThreadFactory
-import com.android.app.tracing.traceSection
-import com.android.keyguard.logging.ScrimLogger
 import com.android.wm.shell.displayareahelper.DisplayAreaHelper
 import java.util.Optional
 import java.util.concurrent.Executor
 import java.util.function.Consumer
 import javax.inject.Inject
+import javax.inject.Provider
 
 @SysUIUnfoldScope
 class UnfoldLightRevealOverlayAnimation
@@ -65,11 +68,14 @@
     private val deviceStateManager: DeviceStateManager,
     private val contentResolver: ContentResolver,
     private val displayManager: DisplayManager,
-    private val unfoldTransitionProgressProvider: UnfoldTransitionProgressProvider,
+    @UnfoldBg
+    private val unfoldTransitionBgProgressProvider: Provider<UnfoldTransitionProgressProvider>,
+    private val unfoldTransitionProgressProvider: Provider<UnfoldTransitionProgressProvider>,
     private val displayAreaHelper: Optional<DisplayAreaHelper>,
     @Main private val executor: Executor,
     private val threadFactory: ThreadFactory,
-    private val rotationChangeProvider: RotationChangeProvider,
+    @UnfoldBg private val rotationChangeProvider: RotationChangeProvider,
+    @UnfoldBg private val unfoldProgressHandler: Handler,
     private val displayTracker: DisplayTracker,
     private val scrimLogger: ScrimLogger,
 ) {
@@ -96,11 +102,15 @@
     fun init() {
         // This method will be called only on devices where this animation is enabled,
         // so normally this thread won't be created
-        bgHandler = threadFactory.buildHandlerOnNewThread(TAG)
+        bgHandler = unfoldProgressHandler
         bgExecutor = threadFactory.buildDelayableExecutorOnHandler(bgHandler)
 
         deviceStateManager.registerCallback(bgExecutor, FoldListener())
-        unfoldTransitionProgressProvider.addCallback(transitionListener)
+        if (unfoldAnimationBackgroundProgress()) {
+            unfoldTransitionBgProgressProvider.get().addCallback(transitionListener)
+        } else {
+            unfoldTransitionProgressProvider.get().addCallback(transitionListener)
+        }
         rotationChangeProvider.addCallback(rotationWatcher)
 
         val containerBuilder =
@@ -169,8 +179,13 @@
 
         overlayAddReason = reason
 
-        val newRoot = SurfaceControlViewHost(context, context.display!!, wwm,
-                "UnfoldLightRevealOverlayAnimation")
+        val newRoot =
+            SurfaceControlViewHost(
+                context,
+                context.display,
+                wwm,
+                "UnfoldLightRevealOverlayAnimation"
+            )
         val params = getLayoutParams()
         val newView =
             LightRevealScrim(
@@ -353,12 +368,13 @@
     }
 
     private fun executeInBackground(f: () -> Unit) {
-        check(Looper.myLooper() != bgHandler.looper) {
-            "Trying to execute using background handler while already running" +
-                " in the background handler"
+        // This is needed to allow progresses to be received both from the main thread (that will
+        // schedule a runnable on the bg thread), and from the bg thread directly (no reposting).
+        if (bgHandler.looper.isCurrentThread) {
+            f()
+        } else {
+            bgHandler.post(f)
         }
-        // The UiBackground executor is not used as it doesn't have a prepared looper.
-        bgHandler.post(f)
     }
 
     private fun ensureInBackground() {
diff --git a/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTraceLogger.kt b/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTraceLogger.kt
index 12b8845..94912bf8 100644
--- a/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTraceLogger.kt
+++ b/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTraceLogger.kt
@@ -21,11 +21,14 @@
 import com.android.systemui.CoreStartable
 import com.android.systemui.dagger.SysUISingleton
 import com.android.systemui.dagger.qualifiers.Application
+import com.android.systemui.dagger.qualifiers.Background
 import com.android.systemui.unfold.system.DeviceStateRepository
 import com.android.systemui.unfold.updates.FoldStateRepository
 import javax.inject.Inject
+import kotlin.coroutines.CoroutineContext
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.plus
 
 /**
  * Logs several unfold related details in a trace. Mainly used for debugging and investigate
@@ -37,7 +40,8 @@
 constructor(
     private val context: Context,
     private val foldStateRepository: FoldStateRepository,
-    @Application private val applicationScope: CoroutineScope,
+    @Application applicationScope: CoroutineScope,
+    @Background private val coroutineContext: CoroutineContext,
     private val deviceStateRepository: DeviceStateRepository
 ) : CoreStartable {
     private val isFoldable: Boolean
@@ -46,20 +50,22 @@
                 .getIntArray(com.android.internal.R.array.config_foldedDeviceStates)
                 .isNotEmpty()
 
+    private val bgScope = applicationScope.plus(coroutineContext)
+
     override fun start() {
         if (!isFoldable) return
 
-        applicationScope.launch {
+        bgScope.launch {
             val foldUpdateLogger = TraceStateLogger("FoldUpdate")
             foldStateRepository.foldUpdate.collect { foldUpdateLogger.log(it.name) }
         }
 
-        applicationScope.launch {
+        bgScope.launch {
             foldStateRepository.hingeAngle.collect {
                 Trace.traceCounter(Trace.TRACE_TAG_APP, "hingeAngle", it.toInt())
             }
         }
-        applicationScope.launch {
+        bgScope.launch {
             val foldedStateLogger = TraceStateLogger("FoldedState")
             deviceStateRepository.isFolded.collect { isFolded ->
                 foldedStateLogger.log(
diff --git a/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTransitionModule.kt b/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTransitionModule.kt
index 7b628f8..0531487 100644
--- a/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTransitionModule.kt
+++ b/packages/SystemUI/src/com/android/systemui/unfold/UnfoldTransitionModule.kt
@@ -24,6 +24,7 @@
 import com.android.systemui.dagger.qualifiers.Main
 import com.android.systemui.keyguard.LifecycleScreenStatusProvider
 import com.android.systemui.unfold.config.UnfoldTransitionConfig
+import com.android.systemui.unfold.dagger.UnfoldMain
 import com.android.systemui.unfold.data.repository.UnfoldTransitionRepository
 import com.android.systemui.unfold.data.repository.UnfoldTransitionRepositoryImpl
 import com.android.systemui.unfold.domain.interactor.UnfoldTransitionInteractor
@@ -102,7 +103,7 @@
     @Singleton
     fun provideNaturalRotationProgressProvider(
         context: Context,
-        rotationChangeProvider: RotationChangeProvider,
+        @UnfoldMain rotationChangeProvider: RotationChangeProvider,
         unfoldTransitionProgressProvider: Optional<UnfoldTransitionProgressProvider>
     ): Optional<NaturalRotationUnfoldProgressProvider> =
         unfoldTransitionProgressProvider.map { provider ->
@@ -153,7 +154,8 @@
 
         return resultingProvider?.get()?.orElse(null)?.let { unfoldProgressProvider ->
             UnfoldProgressProvider(unfoldProgressProvider, foldProvider)
-        } ?: ShellUnfoldProgressProvider.NO_PROVIDER
+        }
+            ?: ShellUnfoldProgressProvider.NO_PROVIDER
     }
 
     @Provides
diff --git a/packages/SystemUI/tests/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProviderTest.kt b/packages/SystemUI/tests/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProviderTest.kt
index 9fe2f56..14fb054 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProviderTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProviderTest.kt
@@ -15,9 +15,10 @@
  */
 package com.android.systemui.unfold.progress
 
+import android.os.Handler
+import android.os.HandlerThread
 import android.testing.AndroidTestingRunner
 import androidx.test.filters.SmallTest
-import androidx.test.platform.app.InstrumentationRegistry
 import com.android.systemui.SysuiTestCase
 import com.android.systemui.unfold.UnfoldTransitionProgressProvider
 import com.android.systemui.unfold.updates.FOLD_UPDATE_FINISH_CLOSED
@@ -26,6 +27,8 @@
 import com.android.systemui.unfold.updates.FOLD_UPDATE_START_CLOSING
 import com.android.systemui.unfold.updates.FOLD_UPDATE_START_OPENING
 import com.android.systemui.unfold.util.TestFoldStateProvider
+import com.android.systemui.util.mockito.mock
+import com.android.systemui.util.mockito.whenever
 import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -37,16 +40,28 @@
     private val foldStateProvider: TestFoldStateProvider = TestFoldStateProvider()
     private val listener = TestUnfoldProgressListener()
     private lateinit var progressProvider: UnfoldTransitionProgressProvider
+    private val schedulerFactory =
+        mock<UnfoldFrameCallbackScheduler.Factory>().apply {
+            whenever(create()).then { UnfoldFrameCallbackScheduler() }
+        }
+    private val mockBgHandler = mock<Handler>()
+    private val fakeHandler = Handler(HandlerThread("UnfoldBg").apply { start() }.looper)
 
     @Before
     fun setUp() {
-        progressProvider = PhysicsBasedUnfoldTransitionProgressProvider(context, foldStateProvider)
+        progressProvider =
+            PhysicsBasedUnfoldTransitionProgressProvider(
+                context,
+                schedulerFactory,
+                foldStateProvider = foldStateProvider,
+                progressHandler = fakeHandler
+            )
         progressProvider.addCallback(listener)
     }
 
     @Test
     fun testUnfold_emitsIncreasingTransitionEvents() {
-        runOnMainThreadWithInterval(
+        runOnProgressThreadWithInterval(
             { foldStateProvider.sendFoldUpdate(FOLD_UPDATE_START_OPENING) },
             { foldStateProvider.sendHingeAngleUpdate(10f) },
             { foldStateProvider.sendUnfoldedScreenAvailable() },
@@ -63,7 +78,7 @@
 
     @Test
     fun testUnfold_emitsFinishingEvent() {
-        runOnMainThreadWithInterval(
+        runOnProgressThreadWithInterval(
             { foldStateProvider.sendFoldUpdate(FOLD_UPDATE_START_OPENING) },
             { foldStateProvider.sendHingeAngleUpdate(10f) },
             { foldStateProvider.sendUnfoldedScreenAvailable() },
@@ -77,7 +92,7 @@
 
     @Test
     fun testUnfold_screenAvailableOnlyAfterFullUnfold_emitsIncreasingTransitionEvents() {
-        runOnMainThreadWithInterval(
+        runOnProgressThreadWithInterval(
             { foldStateProvider.sendFoldUpdate(FOLD_UPDATE_START_OPENING) },
             { foldStateProvider.sendHingeAngleUpdate(10f) },
             { foldStateProvider.sendHingeAngleUpdate(90f) },
@@ -94,7 +109,7 @@
 
     @Test
     fun testFold_emitsDecreasingTransitionEvents() {
-        runOnMainThreadWithInterval(
+        runOnProgressThreadWithInterval(
             { foldStateProvider.sendFoldUpdate(FOLD_UPDATE_START_CLOSING) },
             { foldStateProvider.sendHingeAngleUpdate(170f) },
             { foldStateProvider.sendHingeAngleUpdate(90f) },
@@ -110,7 +125,7 @@
 
     @Test
     fun testUnfoldAndStopUnfolding_finishesTheUnfoldTransition() {
-        runOnMainThreadWithInterval(
+        runOnProgressThreadWithInterval(
             { foldStateProvider.sendFoldUpdate(FOLD_UPDATE_START_OPENING) },
             { foldStateProvider.sendUnfoldedScreenAvailable() },
             { foldStateProvider.sendHingeAngleUpdate(10f) },
@@ -126,7 +141,7 @@
 
     @Test
     fun testFoldImmediatelyAfterUnfold_runsFoldAnimation() {
-        runOnMainThreadWithInterval(
+        runOnProgressThreadWithInterval(
             { foldStateProvider.sendFoldUpdate(FOLD_UPDATE_START_OPENING) },
             { foldStateProvider.sendUnfoldedScreenAvailable() },
             { foldStateProvider.sendHingeAngleUpdate(10f) },
@@ -144,9 +159,12 @@
         with(listener.ensureTransitionFinished()) { assertHasFoldAnimationAtTheEnd() }
     }
 
-    private fun runOnMainThreadWithInterval(vararg blocks: () -> Unit, intervalMillis: Long = 60) {
+    private fun runOnProgressThreadWithInterval(
+        vararg blocks: () -> Unit,
+        intervalMillis: Long = 60,
+    ) {
         blocks.forEach {
-            InstrumentationRegistry.getInstrumentation().runOnMainSync { it() }
+            fakeHandler.post(it)
             Thread.sleep(intervalMillis)
         }
     }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/unfold/updates/DeviceFoldStateProviderTest.kt b/packages/SystemUI/tests/src/com/android/systemui/unfold/updates/DeviceFoldStateProviderTest.kt
index aa49287..552b60c 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/unfold/updates/DeviceFoldStateProviderTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/unfold/updates/DeviceFoldStateProviderTest.kt
@@ -37,7 +37,6 @@
 import com.android.systemui.unfold.util.UnfoldKeyguardVisibilityProvider
 import com.android.systemui.util.mockito.any
 import com.android.systemui.util.mockito.capture
-import com.android.systemui.util.mockito.mock
 import com.google.common.truth.Truth.assertThat
 import junit.framework.Assert.fail
 import java.util.concurrent.Executor
@@ -105,16 +104,15 @@
 
         foldStateProvider =
             DeviceFoldStateProvider(
-                config,
-                testHingeAngleProvider,
-                screenOnStatusProvider,
-                foldProvider,
-                activityTypeProvider,
-                unfoldKeyguardVisibilityProvider,
-                rotationChangeProvider,
-                context,
-                context.mainExecutor,
-                handler
+                    config,
+                    context,
+                    screenOnStatusProvider,
+                    activityTypeProvider,
+                    unfoldKeyguardVisibilityProvider,
+                    foldProvider,
+                    testHingeAngleProvider,
+                    rotationChangeProvider,
+                    handler
             )
 
         foldStateProvider.addCallback(
@@ -151,6 +149,12 @@
             null
         }
 
+        whenever(handler.post(any<Runnable>())).then { invocationOnMock ->
+            val runnable = invocationOnMock.getArgument<Runnable>(0)
+            runnable.run()
+            null
+        }
+
         // By default, we're on launcher.
         setupForegroundActivityType(isHomeActivity = true)
         setIsLargeScreen(true)
@@ -171,7 +175,7 @@
     }
 
     @Test
-    fun testOnUnfold_hingeAngleDecreasesBeforeInnerScreenAvailable_emitsOnlyStartAndInnerScreenAvailableEvents() {
+    fun onUnfold_angleDecrBeforeInnerScrAvailable_emitsOnlyStartAndInnerScrAvailableEvents() {
         setFoldState(folded = true)
         foldUpdates.clear()
 
@@ -187,7 +191,7 @@
     }
 
     @Test
-    fun testOnUnfold_hingeAngleDecreasesAfterInnerScreenAvailable_emitsStartInnerScreenAvailableAndStartClosingEvents() {
+    fun onUnfold_angleDecrAfterInnerScrAvailable_emitsStartInnerScrAvailableAndStartClosingEvnts() {
         setFoldState(folded = true)
         foldUpdates.clear()
 
@@ -690,7 +694,7 @@
             callbacks.forEach { it.onFoldUpdated(isFolded) }
         }
 
-        fun getNumberOfCallbacks(): Int{
+        fun getNumberOfCallbacks(): Int {
             return callbacks.size
         }
     }
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldRemoteModule.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldRemoteModule.kt
index a639df5..2bc2db3 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldRemoteModule.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldRemoteModule.kt
@@ -16,9 +16,12 @@
 
 package com.android.systemui.unfold
 
+import android.os.Handler
 import com.android.systemui.unfold.config.UnfoldTransitionConfig
+import com.android.systemui.unfold.dagger.UnfoldMain
 import com.android.systemui.unfold.dagger.UseReceivingFilter
 import com.android.systemui.unfold.progress.RemoteUnfoldTransitionReceiver
+import com.android.systemui.unfold.updates.RotationChangeProvider
 import com.android.systemui.unfold.util.ATraceLoggerTransitionProgressListener
 import dagger.Module
 import dagger.Provides
@@ -33,16 +36,25 @@
     @Singleton
     fun provideTransitionProvider(
         config: UnfoldTransitionConfig,
-        traceListener: ATraceLoggerTransitionProgressListener,
+        traceListener: ATraceLoggerTransitionProgressListener.Factory,
         remoteReceiverProvider: Provider<RemoteUnfoldTransitionReceiver>,
     ): Optional<RemoteUnfoldTransitionReceiver> {
         if (!config.isEnabled) {
             return Optional.empty()
         }
         val remoteReceiver = remoteReceiverProvider.get()
-        remoteReceiver.addCallback(traceListener)
+        remoteReceiver.addCallback(traceListener.create("remoteReceiver"))
         return Optional.of(remoteReceiver)
     }
 
     @Provides @UseReceivingFilter fun useReceivingFilter(): Boolean = true
+
+    @Provides
+    @UnfoldMain
+    fun provideMainRotationChangeProvider(
+        rotationChangeProviderFactory: RotationChangeProvider.Factory,
+        @UnfoldMain mainHandler: Handler,
+    ): RotationChangeProvider {
+        return rotationChangeProviderFactory.create(mainHandler)
+    }
 }
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedComponent.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedComponent.kt
index c3a6cf0..31b7ccc 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedComponent.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedComponent.kt
@@ -22,12 +22,12 @@
 import android.hardware.display.DisplayManager
 import android.os.Handler
 import com.android.systemui.unfold.config.UnfoldTransitionConfig
+import com.android.systemui.unfold.dagger.UnfoldBg
 import com.android.systemui.unfold.dagger.UnfoldMain
 import com.android.systemui.unfold.dagger.UnfoldSingleThreadBg
 import com.android.systemui.unfold.progress.RemoteUnfoldTransitionReceiver
 import com.android.systemui.unfold.updates.FoldProvider
 import com.android.systemui.unfold.updates.RotationChangeProvider
-import com.android.systemui.unfold.updates.hinge.HingeAngleProvider
 import com.android.systemui.unfold.updates.screen.ScreenStatusProvider
 import com.android.systemui.unfold.util.CurrentActivityTypeProvider
 import com.android.systemui.unfold.util.UnfoldTransitionATracePrefix
@@ -63,13 +63,12 @@
             @BindsInstance @UnfoldSingleThreadBg singleThreadBgExecutor: Executor,
             @BindsInstance @UnfoldTransitionATracePrefix tracingTagPrefix: String,
             @BindsInstance displayManager: DisplayManager,
-            @BindsInstance contentResolver: ContentResolver = context.contentResolver
+            @BindsInstance @UnfoldBg bgHandler: Handler,
+            @BindsInstance contentResolver: ContentResolver = context.contentResolver,
         ): UnfoldSharedComponent
     }
 
     val unfoldTransitionProvider: Optional<UnfoldTransitionProgressProvider>
-    val hingeAngleProvider: HingeAngleProvider
-    val rotationChangeProvider: RotationChangeProvider
 }
 
 /**
@@ -94,7 +93,8 @@
     }
 
     val remoteTransitionProgress: Optional<RemoteUnfoldTransitionReceiver>
-    val rotationChangeProvider: RotationChangeProvider
+
+    @UnfoldMain fun getRotationChangeProvider(): RotationChangeProvider
 }
 
 /**
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedModule.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedModule.kt
index 7473ca6..42d31b3 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedModule.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldSharedModule.kt
@@ -16,7 +16,10 @@
 
 package com.android.systemui.unfold
 
+import android.os.Handler
 import com.android.systemui.unfold.config.UnfoldTransitionConfig
+import com.android.systemui.unfold.dagger.UnfoldBg
+import com.android.systemui.unfold.dagger.UnfoldMain
 import com.android.systemui.unfold.progress.FixedTimingTransitionProgressProvider
 import com.android.systemui.unfold.progress.PhysicsBasedUnfoldTransitionProgressProvider
 import com.android.systemui.unfold.progress.UnfoldTransitionProgressForwarder
@@ -24,6 +27,7 @@
 import com.android.systemui.unfold.updates.FoldStateProvider
 import com.android.systemui.unfold.updates.FoldStateRepository
 import com.android.systemui.unfold.updates.FoldStateRepositoryImpl
+import com.android.systemui.unfold.updates.RotationChangeProvider
 import com.android.systemui.unfold.updates.hinge.EmptyHingeAngleProvider
 import com.android.systemui.unfold.updates.hinge.HingeAngleProvider
 import com.android.systemui.unfold.updates.hinge.HingeSensorAngleProvider
@@ -38,16 +42,18 @@
 import javax.inject.Provider
 import javax.inject.Singleton
 
-@Module(includes = [UnfoldSharedInternalModule::class])
+@Module(
+    includes =
+        [
+            UnfoldSharedInternalModule::class,
+            UnfoldRotationProviderInternalModule::class,
+            HingeAngleProviderInternalModule::class,
+            FoldStateProviderModule::class,
+        ]
+)
 class UnfoldSharedModule {
     @Provides
     @Singleton
-    fun provideFoldStateProvider(
-        deviceFoldStateProvider: DeviceFoldStateProvider
-    ): FoldStateProvider = deviceFoldStateProvider
-
-    @Provides
-    @Singleton
     fun unfoldKeyguardVisibilityProvider(
         impl: UnfoldKeyguardVisibilityManagerImpl
     ): UnfoldKeyguardVisibilityProvider = impl
@@ -60,9 +66,7 @@
 
     @Provides
     @Singleton
-    fun foldStateRepository(
-            impl: FoldStateRepositoryImpl
-    ): FoldStateRepository = impl
+    fun foldStateRepository(impl: FoldStateRepositoryImpl): FoldStateRepository = impl
 }
 
 /**
@@ -77,17 +81,69 @@
     fun unfoldTransitionProgressProvider(
         config: UnfoldTransitionConfig,
         scaleAwareProviderFactory: ScaleAwareTransitionProgressProvider.Factory,
+        tracingListener: ATraceLoggerTransitionProgressListener.Factory,
+        physicsBasedUnfoldTransitionProgressProvider:
+            PhysicsBasedUnfoldTransitionProgressProvider.Factory,
+        fixedTimingTransitionProgressProvider: Provider<FixedTimingTransitionProgressProvider>,
+        foldStateProvider: FoldStateProvider,
+        @UnfoldMain mainHandler: Handler,
+    ): Optional<UnfoldTransitionProgressProvider> {
+        return createOptionalUnfoldTransitionProgressProvider(
+            config = config,
+            scaleAwareProviderFactory = scaleAwareProviderFactory,
+            tracingListener = tracingListener.create("MainThread"),
+            physicsBasedUnfoldTransitionProgressProvider =
+                physicsBasedUnfoldTransitionProgressProvider,
+            fixedTimingTransitionProgressProvider = fixedTimingTransitionProgressProvider,
+            foldStateProvider = foldStateProvider,
+            progressHandler = mainHandler,
+        )
+    }
+
+    @Provides
+    @Singleton
+    @UnfoldBg
+    fun unfoldBgTransitionProgressProvider(
+        config: UnfoldTransitionConfig,
+        scaleAwareProviderFactory: ScaleAwareTransitionProgressProvider.Factory,
+        tracingListener: ATraceLoggerTransitionProgressListener.Factory,
+        physicsBasedUnfoldTransitionProgressProvider:
+            PhysicsBasedUnfoldTransitionProgressProvider.Factory,
+        fixedTimingTransitionProgressProvider: Provider<FixedTimingTransitionProgressProvider>,
+        @UnfoldBg bgFoldStateProvider: FoldStateProvider,
+        @UnfoldBg bgHandler: Handler,
+    ): Optional<UnfoldTransitionProgressProvider> {
+        return createOptionalUnfoldTransitionProgressProvider(
+            config = config,
+            scaleAwareProviderFactory = scaleAwareProviderFactory,
+            tracingListener = tracingListener.create("BgThread"),
+            physicsBasedUnfoldTransitionProgressProvider =
+                physicsBasedUnfoldTransitionProgressProvider,
+            fixedTimingTransitionProgressProvider = fixedTimingTransitionProgressProvider,
+            foldStateProvider = bgFoldStateProvider,
+            progressHandler = bgHandler,
+        )
+    }
+
+    private fun createOptionalUnfoldTransitionProgressProvider(
+        config: UnfoldTransitionConfig,
+        scaleAwareProviderFactory: ScaleAwareTransitionProgressProvider.Factory,
         tracingListener: ATraceLoggerTransitionProgressListener,
         physicsBasedUnfoldTransitionProgressProvider:
-            Provider<PhysicsBasedUnfoldTransitionProgressProvider>,
+            PhysicsBasedUnfoldTransitionProgressProvider.Factory,
         fixedTimingTransitionProgressProvider: Provider<FixedTimingTransitionProgressProvider>,
+        foldStateProvider: FoldStateProvider,
+        progressHandler: Handler,
     ): Optional<UnfoldTransitionProgressProvider> {
         if (!config.isEnabled) {
             return Optional.empty()
         }
         val baseProgressProvider =
             if (config.isHingeAngleEnabled) {
-                physicsBasedUnfoldTransitionProgressProvider.get()
+                physicsBasedUnfoldTransitionProgressProvider.create(
+                    foldStateProvider,
+                    progressHandler
+                )
             } else {
                 fixedTimingTransitionProgressProvider.get()
             }
@@ -101,26 +157,105 @@
     }
 
     @Provides
+    @Singleton
+    fun provideProgressForwarder(
+        config: UnfoldTransitionConfig,
+        progressForwarder: Provider<UnfoldTransitionProgressForwarder>
+    ): Optional<UnfoldTransitionProgressForwarder> {
+        if (!config.isEnabled) {
+            return Optional.empty()
+        }
+        return Optional.of(progressForwarder.get())
+    }
+}
+
+/**
+ * Provides [FoldStateProvider]. The [UnfoldBg] annotated binding sends progress in the [UnfoldBg]
+ * handler.
+ */
+@Module
+internal class FoldStateProviderModule {
+    @Provides
+    @Singleton
+    fun provideFoldStateProvider(
+        factory: DeviceFoldStateProvider.Factory,
+        @UnfoldMain hingeAngleProvider: HingeAngleProvider,
+        @UnfoldMain rotationChangeProvider: RotationChangeProvider,
+        @UnfoldMain mainHandler: Handler,
+    ): FoldStateProvider =
+        factory.create(
+            hingeAngleProvider,
+            rotationChangeProvider,
+            progressHandler = mainHandler
+        )
+
+    @Provides
+    @Singleton
+    @UnfoldBg
+    fun provideBgFoldStateProvider(
+        factory: DeviceFoldStateProvider.Factory,
+        @UnfoldBg hingeAngleProvider: HingeAngleProvider,
+        @UnfoldBg rotationChangeProvider: RotationChangeProvider,
+        @UnfoldBg bgHandler: Handler,
+    ): FoldStateProvider =
+        factory.create(
+            hingeAngleProvider,
+            rotationChangeProvider,
+            progressHandler = bgHandler
+        )
+}
+
+/** Provides bindings for both [UnfoldMain] and [UnfoldBg] [HingeAngleProvider]. */
+@Module
+internal class HingeAngleProviderInternalModule {
+    @Provides
+    @UnfoldMain
     fun hingeAngleProvider(
         config: UnfoldTransitionConfig,
-        hingeAngleSensorProvider: Provider<HingeSensorAngleProvider>
+        @UnfoldMain handler: Handler,
+        hingeAngleSensorProvider: HingeSensorAngleProvider.Factory
     ): HingeAngleProvider {
         return if (config.isHingeAngleEnabled) {
-            hingeAngleSensorProvider.get()
+            hingeAngleSensorProvider.create(handler)
         } else {
             EmptyHingeAngleProvider
         }
     }
 
     @Provides
-    @Singleton
-    fun provideProgressForwarder(
-            config: UnfoldTransitionConfig,
-            progressForwarder: Provider<UnfoldTransitionProgressForwarder>
-    ): Optional<UnfoldTransitionProgressForwarder> {
-        if (!config.isEnabled) {
-            return Optional.empty()
+    @UnfoldBg
+    fun hingeAngleProviderBg(
+        config: UnfoldTransitionConfig,
+        @UnfoldBg handler: Handler,
+        hingeAngleSensorProvider: HingeSensorAngleProvider.Factory
+    ): HingeAngleProvider {
+        return if (config.isHingeAngleEnabled) {
+            hingeAngleSensorProvider.create(handler)
+        } else {
+            EmptyHingeAngleProvider
         }
-        return Optional.of(progressForwarder.get())
+    }
+}
+
+@Module
+internal class UnfoldRotationProviderInternalModule {
+    @Provides
+    @Singleton
+    @UnfoldMain
+    fun provideRotationChangeProvider(
+        rotationChangeProviderFactory: RotationChangeProvider.Factory,
+        @UnfoldMain mainHandler: Handler,
+    ): RotationChangeProvider {
+        return rotationChangeProviderFactory.create(mainHandler)
+    }
+
+    @Provides
+    @Singleton
+    @UnfoldBg
+    fun provideBgRotationChangeProvider(
+        rotationChangeProviderFactory: RotationChangeProvider.Factory,
+        @UnfoldBg bgHandler: Handler,
+    ): RotationChangeProvider {
+        return rotationChangeProviderFactory.create(bgHandler)
     }
 }
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionFactory.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionFactory.kt
index 1839919..1cbaf31 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionFactory.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/UnfoldTransitionFactory.kt
@@ -48,6 +48,7 @@
         singleThreadBgExecutor: Executor,
         tracingTagPrefix: String,
         displayManager: DisplayManager,
+        bgHandler: Handler,
 ): UnfoldSharedComponent =
         DaggerUnfoldSharedComponent.factory()
                 .create(
@@ -62,6 +63,7 @@
                         singleThreadBgExecutor,
                         tracingTagPrefix,
                         displayManager,
+                        bgHandler,
                 )
 
 /**
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/dagger/UnfoldBg.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/dagger/UnfoldBg.kt
new file mode 100644
index 0000000..7cd4419
--- /dev/null
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/dagger/UnfoldBg.kt
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2023 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.unfold.dagger
+
+import javax.inject.Qualifier
+
+/** Annotation for background computations related to unfold lib. */
+@Qualifier @Retention(AnnotationRetention.RUNTIME) annotation class UnfoldBg
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProvider.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProvider.kt
index f8f168b..907bf46 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProvider.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/progress/PhysicsBasedUnfoldTransitionProgressProvider.kt
@@ -20,6 +20,7 @@
 import android.animation.ObjectAnimator
 import android.animation.ValueAnimator
 import android.content.Context
+import android.os.Handler
 import android.os.Trace
 import android.util.FloatProperty
 import android.util.Log
@@ -38,13 +39,25 @@
 import com.android.systemui.unfold.updates.FoldStateProvider.FoldUpdate
 import com.android.systemui.unfold.updates.FoldStateProvider.FoldUpdatesListener
 import com.android.systemui.unfold.updates.name
-import javax.inject.Inject
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
 
-/** Maps fold updates to unfold transition progress using DynamicAnimation. */
+/**
+ * Maps fold updates to unfold transition progress using DynamicAnimation.
+ *
+ * Note that all variable accesses must be done in the [Handler] provided in the constructor, that
+ * might be different than [mainHandler]. When a custom handler is provided, the [SpringAnimation]
+ * uses a scheduler different than the default one.
+ */
 class PhysicsBasedUnfoldTransitionProgressProvider
-@Inject
-constructor(context: Context, private val foldStateProvider: FoldStateProvider) :
-    UnfoldTransitionProgressProvider, FoldUpdatesListener, DynamicAnimation.OnAnimationEndListener {
+@AssistedInject
+constructor(
+    context: Context,
+    private val schedulerFactory: UnfoldFrameCallbackScheduler.Factory,
+    @Assisted private val foldStateProvider: FoldStateProvider,
+    @Assisted private val progressHandler: Handler,
+) : UnfoldTransitionProgressProvider, FoldUpdatesListener, DynamicAnimation.OnAnimationEndListener {
 
     private val emphasizedInterpolator =
         loadInterpolator(context, android.R.interpolator.fast_out_extra_slow_in)
@@ -63,6 +76,7 @@
 
     private var transitionProgress: Float = 0.0f
         set(value) {
+            assertInProgressThread()
             if (isTransitionRunning) {
                 listeners.forEach { it.onTransitionProgress(value) }
             }
@@ -72,8 +86,14 @@
     private val listeners: MutableList<TransitionProgressListener> = mutableListOf()
 
     init {
-        foldStateProvider.addCallback(this)
-        foldStateProvider.start()
+        progressHandler.post {
+            // The scheduler needs to be created in the progress handler in order to get the correct
+            // choreographer and frame callbacks. This is because the choreographer can be get only
+            // as a thread local.
+            springAnimation.scheduler = schedulerFactory.create()
+            foldStateProvider.addCallback(this)
+            foldStateProvider.start()
+        }
     }
 
     override fun destroy() {
@@ -81,6 +101,8 @@
     }
 
     override fun onHingeAngleUpdate(angle: Float) {
+        assertInProgressThread()
+
         if (!isTransitionRunning || isAnimatedCancelRunning) return
         val progress = saturate(angle / FINAL_HINGE_ANGLE_POSITION)
         springAnimation.animateToFinalPosition(progress)
@@ -90,6 +112,7 @@
         if (amount < low) low else if (amount > high) high else amount
 
     override fun onFoldUpdate(@FoldUpdate update: Int) {
+        assertInProgressThread()
         when (update) {
             FOLD_UPDATE_FINISH_FULL_OPEN,
             FOLD_UPDATE_FINISH_HALF_OPEN -> {
@@ -148,6 +171,7 @@
     }
 
     private fun cancelTransition(endValue: Float, animate: Boolean) {
+        assertInProgressThread()
         if (isTransitionRunning && animate) {
             if (endValue == 1.0f && !isAnimatedCancelRunning) {
                 listeners.forEach { it.onTransitionFinishing() }
@@ -165,7 +189,6 @@
             isAnimatedCancelRunning = false
             isTransitionRunning = false
             springAnimation.cancel()
-
             cannedAnimator?.removeAllListeners()
             cannedAnimator?.cancel()
             cannedAnimator = null
@@ -182,7 +205,7 @@
         animation: DynamicAnimation<out DynamicAnimation<*>>,
         canceled: Boolean,
         value: Float,
-        velocity: Float
+        velocity: Float,
     ) {
         if (isAnimatedCancelRunning) {
             cancelTransition(value, animate = false)
@@ -202,6 +225,7 @@
     }
 
     private fun startTransition(startValue: Float) {
+        assertInProgressThread()
         if (!isTransitionRunning) onStartTransition()
 
         springAnimation.apply {
@@ -221,14 +245,16 @@
     }
 
     override fun addCallback(listener: TransitionProgressListener) {
-        listeners.add(listener)
+        progressHandler.post { listeners.add(listener) }
     }
 
     override fun removeCallback(listener: TransitionProgressListener) {
-        listeners.remove(listener)
+        progressHandler.post { listeners.remove(listener) }
     }
 
     private fun startCannedCancelAnimation() {
+        assertInProgressThread()
+
         cannedAnimator?.cancel()
         cannedAnimator = null
 
@@ -264,7 +290,7 @@
 
         override fun setValue(
             provider: PhysicsBasedUnfoldTransitionProgressProvider,
-            value: Float
+            value: Float,
         ) {
             provider.transitionProgress = value
         }
@@ -272,6 +298,25 @@
         override fun get(provider: PhysicsBasedUnfoldTransitionProgressProvider): Float =
             provider.transitionProgress
     }
+
+    private fun assertInProgressThread() {
+        check(progressHandler.looper.isCurrentThread) {
+            val progressThread = progressHandler.looper.thread
+            val thisThread = Thread.currentThread()
+            """should be called from the progress thread.
+                progressThread=$progressThread tid=${progressThread.id}
+                Thread.currentThread()=$thisThread tid=${thisThread.id}"""
+                .trimMargin()
+        }
+    }
+
+    @AssistedFactory
+    interface Factory {
+        fun create(
+            foldStateProvider: FoldStateProvider,
+            handler: Handler,
+        ): PhysicsBasedUnfoldTransitionProgressProvider
+    }
 }
 
 private const val TAG = "PhysicsBasedUnfoldTransitionProgressProvider"
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/progress/UnfoldFrameCallbackScheduler.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/progress/UnfoldFrameCallbackScheduler.kt
new file mode 100644
index 0000000..1dffd84
--- /dev/null
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/progress/UnfoldFrameCallbackScheduler.kt
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2023 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.unfold.progress
+
+import android.os.Looper
+import android.view.Choreographer
+import androidx.dynamicanimation.animation.FrameCallbackScheduler
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
+
+/**
+ * Scheduler that posts animation progresses on a thread different than the ui one.
+ *
+ * The following is taken from [AnimationHandler.FrameCallbackScheduler16]. It is extracted here as
+ * there are no guarantees which implementation the [DynamicAnimation] class would use otherwise.
+ * This allows classes using [DynamicAnimation] to be created in any thread, but still use the
+ * scheduler for a specific thread.
+ *
+ * Technically the [AssistedInject] is not needed: it's just to have a nicer factory with a
+ * documentation snippet instead of using a plain dagger provider.
+ */
+class UnfoldFrameCallbackScheduler @AssistedInject constructor() : FrameCallbackScheduler {
+
+    private val choreographer = Choreographer.getInstance()
+    private val looper =
+        Looper.myLooper() ?: error("This should be created in a thread with a looper.")
+
+    override fun postFrameCallback(frameCallback: Runnable) {
+        choreographer.postFrameCallback { frameCallback.run() }
+    }
+
+    override fun isCurrentThread(): Boolean {
+        return looper.isCurrentThread
+    }
+
+    @AssistedFactory
+    interface Factory {
+        /**
+         * Creates a [FrameCallbackScheduler] that uses [Choreographer] to post frame callbacks.
+         *
+         * Note that the choreographer used depends on the thread this [create] is called on, as it
+         * is get from a thread static attribute.
+         */
+        fun create(): UnfoldFrameCallbackScheduler
+    }
+}
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/DeviceFoldStateProvider.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/DeviceFoldStateProvider.kt
index 003013e..77f637b 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/DeviceFoldStateProvider.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/DeviceFoldStateProvider.kt
@@ -23,37 +23,34 @@
 import androidx.core.util.Consumer
 import com.android.systemui.unfold.compat.INNER_SCREEN_SMALLEST_SCREEN_WIDTH_THRESHOLD_DP
 import com.android.systemui.unfold.config.UnfoldTransitionConfig
-import com.android.systemui.unfold.dagger.UnfoldMain
-import com.android.systemui.unfold.updates.FoldStateProvider.FoldUpdate
-import com.android.systemui.unfold.updates.FoldStateProvider.FoldUpdatesListener
-import com.android.systemui.unfold.updates.RotationChangeProvider.RotationListener
 import com.android.systemui.unfold.updates.hinge.FULLY_CLOSED_DEGREES
 import com.android.systemui.unfold.updates.hinge.FULLY_OPEN_DEGREES
 import com.android.systemui.unfold.updates.hinge.HingeAngleProvider
 import com.android.systemui.unfold.updates.screen.ScreenStatusProvider
 import com.android.systemui.unfold.util.CurrentActivityTypeProvider
 import com.android.systemui.unfold.util.UnfoldKeyguardVisibilityProvider
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
+import java.util.concurrent.CopyOnWriteArrayList
 import java.util.concurrent.Executor
-import javax.inject.Inject
 
 class DeviceFoldStateProvider
-@Inject
+@AssistedInject
 constructor(
     config: UnfoldTransitionConfig,
-    private val hingeAngleProvider: HingeAngleProvider,
+    private val context: Context,
     private val screenStatusProvider: ScreenStatusProvider,
-    private val foldProvider: FoldProvider,
     private val activityTypeProvider: CurrentActivityTypeProvider,
     private val unfoldKeyguardVisibilityProvider: UnfoldKeyguardVisibilityProvider,
-    private val rotationChangeProvider: RotationChangeProvider,
-    private val context: Context,
-    @UnfoldMain private val mainExecutor: Executor,
-    @UnfoldMain private val handler: Handler
+    private val foldProvider: FoldProvider,
+    @Assisted private val hingeAngleProvider: HingeAngleProvider,
+    @Assisted private val rotationChangeProvider: RotationChangeProvider,
+    @Assisted private val progressHandler: Handler,
 ) : FoldStateProvider {
+    private val outputListeners = CopyOnWriteArrayList<FoldStateProvider.FoldUpdatesListener>()
 
-    private val outputListeners: MutableList<FoldUpdatesListener> = mutableListOf()
-
-    @FoldUpdate private var lastFoldUpdate: Int? = null
+    @FoldStateProvider.FoldUpdate private var lastFoldUpdate: Int? = null
 
     @FloatRange(from = 0.0, to = 180.0) private var lastHingeAngle: Float = 0f
     @FloatRange(from = 0.0, to = 180.0) private var lastHingeAngleBeforeTransition: Float = 0f
@@ -61,11 +58,9 @@
     private val hingeAngleListener = HingeAngleListener()
     private val screenListener = ScreenStatusListener()
     private val foldStateListener = FoldStateListener()
-    private val mainLooper = handler.looper
     private val timeoutRunnable = Runnable { cancelAnimation() }
-    private val rotationListener = RotationListener {
-        if (isTransitionInProgress) cancelAnimation()
-    }
+    private val rotationListener = FoldRotationListener()
+    private val progressExecutor = Executor { progressHandler.post(it) }
 
     /**
      * Time after which [FOLD_UPDATE_FINISH_HALF_OPEN] is emitted following a
@@ -80,9 +75,9 @@
     private var isStarted = false
 
     override fun start() {
-        assertMainThread()
         if (isStarted) return
-        foldProvider.registerCallback(foldStateListener, mainExecutor)
+        foldProvider.registerCallback(foldStateListener, progressExecutor)
+        // TODO(b/277879146): get callbacks in the background
         screenStatusProvider.addCallback(screenListener)
         hingeAngleProvider.addCallback(hingeAngleListener)
         rotationChangeProvider.addCallback(rotationListener)
@@ -91,7 +86,6 @@
     }
 
     override fun stop() {
-        assertMainThread()
         screenStatusProvider.removeCallback(screenListener)
         foldProvider.unregisterCallback(foldStateListener)
         hingeAngleProvider.removeCallback(hingeAngleListener)
@@ -101,11 +95,11 @@
         isStarted = false
     }
 
-    override fun addCallback(listener: FoldUpdatesListener) {
+    override fun addCallback(listener: FoldStateProvider.FoldUpdatesListener) {
         outputListeners.add(listener)
     }
 
-    override fun removeCallback(listener: FoldUpdatesListener) {
+    override fun removeCallback(listener: FoldStateProvider.FoldUpdatesListener) {
         outputListeners.remove(listener)
     }
 
@@ -121,6 +115,7 @@
                 lastFoldUpdate == FOLD_UPDATE_START_CLOSING
 
     private fun onHingeAngle(angle: Float) {
+        assertInProgressThread()
         if (DEBUG) {
             Log.d(
                 TAG,
@@ -131,14 +126,14 @@
         }
 
         val currentDirection =
-                if (angle < lastHingeAngle) FOLD_UPDATE_START_CLOSING else FOLD_UPDATE_START_OPENING
+            if (angle < lastHingeAngle) FOLD_UPDATE_START_CLOSING else FOLD_UPDATE_START_OPENING
         if (isTransitionInProgress && currentDirection != lastFoldUpdate) {
             lastHingeAngleBeforeTransition = lastHingeAngle
         }
 
         val isClosing = angle < lastHingeAngleBeforeTransition
         val transitionUpdate =
-                if (isClosing) FOLD_UPDATE_START_CLOSING else FOLD_UPDATE_START_OPENING
+            if (isClosing) FOLD_UPDATE_START_CLOSING else FOLD_UPDATE_START_OPENING
         val angleChangeSurpassedThreshold =
             Math.abs(angle - lastHingeAngleBeforeTransition) > HINGE_ANGLE_CHANGE_THRESHOLD_DEGREES
         val isFullyOpened = FULLY_OPEN_DEGREES - angle < FULLY_OPEN_THRESHOLD_DEGREES
@@ -150,12 +145,12 @@
             angleChangeSurpassedThreshold && // Do not react immediately to small changes in angle
                 eventNotAlreadyDispatched && // we haven't sent transition event already
                 !isFullyOpened && // do not send transition event if we are in fully opened hinge
-                                  // angle range as closing threshold could overlap this range
+                // angle range as closing threshold could overlap this range
                 screenAvailableEventSent && // do not send transition event if we are still in the
-                                            // process of turning on the inner display
+                // process of turning on the inner display
                 isClosingThresholdMet(angle) && // hinge angle is below certain threshold.
                 isOnLargeScreen // Avoids sending closing event when on small screen.
-                                // Start event is sent regardless due to hall sensor.
+        // Start event is sent regardless due to hall sensor.
         ) {
             notifyFoldUpdate(transitionUpdate, lastHingeAngle)
         }
@@ -202,6 +197,7 @@
 
     private inner class FoldStateListener : FoldProvider.FoldCallback {
         override fun onFoldUpdated(isFolded: Boolean) {
+            assertInProgressThread()
             this@DeviceFoldStateProvider.isFolded = isFolded
             lastHingeAngle = FULLY_CLOSED_DEGREES
 
@@ -218,7 +214,14 @@
         }
     }
 
-    private fun notifyFoldUpdate(@FoldUpdate update: Int, angle: Float) {
+    private inner class FoldRotationListener : RotationChangeProvider.RotationListener {
+        override fun onRotationChanged(newRotation: Int) {
+            assertInProgressThread()
+            if (isTransitionInProgress) cancelAnimation()
+        }
+    }
+
+    private fun notifyFoldUpdate(@FoldStateProvider.FoldUpdate update: Int, angle: Float) {
         if (DEBUG) {
             Log.d(TAG, update.name())
         }
@@ -236,11 +239,11 @@
         if (isTransitionInProgress) {
             cancelTimeout()
         }
-        handler.postDelayed(timeoutRunnable, halfOpenedTimeoutMillis.toLong())
+        progressHandler.postDelayed(timeoutRunnable, halfOpenedTimeoutMillis.toLong())
     }
 
     private fun cancelTimeout() {
-        handler.removeCallbacks(timeoutRunnable)
+        progressHandler.removeCallbacks(timeoutRunnable)
     }
 
     private fun cancelAnimation(): Unit =
@@ -249,42 +252,61 @@
     private inner class ScreenStatusListener : ScreenStatusProvider.ScreenListener {
 
         override fun onScreenTurnedOn() {
-            // Trigger this event only if we are unfolded and this is the first screen
-            // turned on event since unfold started. This prevents running the animation when
-            // turning on the internal display using the power button.
-            // Initially isUnfoldHandled is true so it will be reset to false *only* when we
-            // receive 'folded' event. If SystemUI started when device is already folded it will
-            // still receive 'folded' event on startup.
-            if (!isFolded && !isUnfoldHandled) {
-                outputListeners.forEach { it.onUnfoldedScreenAvailable() }
-                isUnfoldHandled = true
+            executeInProgressThread {
+                // Trigger this event only if we are unfolded and this is the first screen
+                // turned on event since unfold started. This prevents running the animation when
+                // turning on the internal display using the power button.
+                // Initially isUnfoldHandled is true so it will be reset to false *only* when we
+                // receive 'folded' event. If SystemUI started when device is already folded it will
+                // still receive 'folded' event on startup.
+                if (!isFolded && !isUnfoldHandled) {
+                    outputListeners.forEach { it.onUnfoldedScreenAvailable() }
+                    isUnfoldHandled = true
+                }
             }
         }
 
         override fun markScreenAsTurnedOn() {
-            if (!isFolded) {
-                isUnfoldHandled = true
+            executeInProgressThread {
+                if (!isFolded) {
+                    isUnfoldHandled = true
+                }
             }
         }
 
         override fun onScreenTurningOn() {
-            isScreenOn = true
-            updateHingeAngleProviderState()
+            executeInProgressThread {
+                isScreenOn = true
+                updateHingeAngleProviderState()
+            }
         }
 
         override fun onScreenTurningOff() {
-            isScreenOn = false
-            updateHingeAngleProviderState()
+            executeInProgressThread {
+                isScreenOn = false
+                updateHingeAngleProviderState()
+            }
+        }
+
+        /**
+         * Needed just for compatibility while not all data sources are providing data in the
+         * background.
+         *
+         * TODO(b/277879146): Remove once ScreeStatusProvider provides in the background.
+         */
+        private fun executeInProgressThread(f: () -> Unit) {
+            progressHandler.post { f() }
         }
     }
 
     private fun isOnLargeScreen(): Boolean {
-      return context.resources.configuration.smallestScreenWidthDp >
-          INNER_SCREEN_SMALLEST_SCREEN_WIDTH_THRESHOLD_DP
+        return context.resources.configuration.smallestScreenWidthDp >
+            INNER_SCREEN_SMALLEST_SCREEN_WIDTH_THRESHOLD_DP
     }
 
     /** While the screen is off or the device is folded, hinge angle updates are not needed. */
     private fun updateHingeAngleProviderState() {
+        assertInProgressThread()
         if (isScreenOn && !isFolded) {
             hingeAngleProvider.start()
         } else {
@@ -294,20 +316,34 @@
 
     private inner class HingeAngleListener : Consumer<Float> {
         override fun accept(angle: Float) {
+            assertInProgressThread()
             onHingeAngle(angle)
         }
     }
 
-    private fun assertMainThread() {
-        check(mainLooper.isCurrentThread) {
-            ("should be called from the main thread." +
-                    " sMainLooper.threadName=" + mainLooper.thread.name +
-                    " Thread.currentThread()=" + Thread.currentThread().name)
+    private fun assertInProgressThread() {
+        check(progressHandler.looper.isCurrentThread) {
+            val progressThread = progressHandler.looper.thread
+            val thisThread = Thread.currentThread()
+            """should be called from the progress thread.
+                progressThread=$progressThread tid=${progressThread.id}
+                Thread.currentThread()=$thisThread tid=${thisThread.id}"""
+                .trimMargin()
         }
     }
+
+    @AssistedFactory
+    interface Factory {
+        /** Creates a [DeviceFoldStateProvider] using the provided dependencies. */
+        fun create(
+            hingeAngleProvider: HingeAngleProvider,
+            rotationChangeProvider: RotationChangeProvider,
+            progressHandler: Handler,
+        ): DeviceFoldStateProvider
+    }
 }
 
-fun @receiver:FoldUpdate Int.name() =
+fun @receiver:FoldStateProvider.FoldUpdate Int.name() =
     when (this) {
         FOLD_UPDATE_START_OPENING -> "START_OPENING"
         FOLD_UPDATE_START_CLOSING -> "START_CLOSING"
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/RotationChangeProvider.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/RotationChangeProvider.kt
index ce8f1a1..82ea362 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/RotationChangeProvider.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/RotationChangeProvider.kt
@@ -20,20 +20,21 @@
 import android.hardware.display.DisplayManager
 import android.os.Handler
 import android.os.RemoteException
-import com.android.systemui.unfold.dagger.UnfoldMain
 import com.android.systemui.unfold.util.CallbackController
-import javax.inject.Inject
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
 
 /**
- * Allows to subscribe to rotation changes. Updates are provided for the display associated
- * to [context].
+ * Allows to subscribe to rotation changes. Updates are provided for the display associated to
+ * [context].
  */
 class RotationChangeProvider
-@Inject
+@AssistedInject
 constructor(
     private val displayManager: DisplayManager,
     private val context: Context,
-    @UnfoldMain private val mainHandler: Handler,
+    @Assisted private val handler: Handler,
 ) : CallbackController<RotationChangeProvider.RotationListener> {
 
     private val listeners = mutableListOf<RotationListener>()
@@ -42,7 +43,7 @@
     private var lastRotation: Int? = null
 
     override fun addCallback(listener: RotationListener) {
-        mainHandler.post {
+        handler.post {
             if (listeners.isEmpty()) {
                 subscribeToRotation()
             }
@@ -51,7 +52,7 @@
     }
 
     override fun removeCallback(listener: RotationListener) {
-        mainHandler.post {
+        handler.post {
             listeners -= listener
             if (listeners.isEmpty()) {
                 unsubscribeToRotation()
@@ -62,7 +63,7 @@
 
     private fun subscribeToRotation() {
         try {
-            displayManager.registerDisplayListener(displayListener, mainHandler)
+            displayManager.registerDisplayListener(displayListener, handler)
         } catch (e: RemoteException) {
             throw e.rethrowFromSystemServer()
         }
@@ -100,4 +101,10 @@
 
         override fun onDisplayRemoved(displayId: Int) {}
     }
+
+    @AssistedFactory
+    interface Factory {
+        /** Creates a new [RotationChangeProvider] that provides updated using [handler]. */
+        fun create(handler: Handler): RotationChangeProvider
+    }
 }
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/hinge/HingeSensorAngleProvider.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/hinge/HingeSensorAngleProvider.kt
index 89fb12e..14c4cc0 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/hinge/HingeSensorAngleProvider.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/updates/hinge/HingeSensorAngleProvider.kt
@@ -18,21 +18,26 @@
 import android.hardware.SensorEvent
 import android.hardware.SensorEventListener
 import android.hardware.SensorManager
+import android.os.Handler
 import android.os.Trace
 import androidx.core.util.Consumer
 import com.android.systemui.unfold.dagger.UnfoldSingleThreadBg
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
+import java.util.concurrent.CopyOnWriteArrayList
 import java.util.concurrent.Executor
-import javax.inject.Inject
 
 internal class HingeSensorAngleProvider
-@Inject
+@AssistedInject
 constructor(
     private val sensorManager: SensorManager,
-    @UnfoldSingleThreadBg private val singleThreadBgExecutor: Executor
+    @UnfoldSingleThreadBg private val singleThreadBgExecutor: Executor,
+    @Assisted private val listenerHandler: Handler,
 ) : HingeAngleProvider {
 
     private val sensorListener = HingeAngleSensorListener()
-    private val listeners: MutableList<Consumer<Float>> = arrayListOf()
+    private val listeners: MutableList<Consumer<Float>> = CopyOnWriteArrayList()
     var started = false
 
     override fun start() {
@@ -43,7 +48,8 @@
             sensorManager.registerListener(
                 sensorListener,
                 sensor,
-                SensorManager.SENSOR_DELAY_FASTEST
+                SensorManager.SENSOR_DELAY_FASTEST,
+                listenerHandler
             )
             Trace.endSection()
 
@@ -75,4 +81,10 @@
             listeners.forEach { it.accept(event.values[0]) }
         }
     }
+
+    @AssistedFactory
+    interface Factory {
+        /** Creates an [HingeSensorAngleProvider] that sends updates using [handler]. */
+        fun create(handler: Handler): HingeSensorAngleProvider
+    }
 }
diff --git a/packages/SystemUI/unfold/src/com/android/systemui/unfold/util/ATraceLoggerTransitionProgressListener.kt b/packages/SystemUI/unfold/src/com/android/systemui/unfold/util/ATraceLoggerTransitionProgressListener.kt
index d8bc018..a31896a 100644
--- a/packages/SystemUI/unfold/src/com/android/systemui/unfold/util/ATraceLoggerTransitionProgressListener.kt
+++ b/packages/SystemUI/unfold/src/com/android/systemui/unfold/util/ATraceLoggerTransitionProgressListener.kt
@@ -16,7 +16,9 @@
 
 import android.os.Trace
 import com.android.systemui.unfold.UnfoldTransitionProgressProvider.TransitionProgressListener
-import javax.inject.Inject
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
 import javax.inject.Qualifier
 
 /**
@@ -26,11 +28,11 @@
  * for each fold/unfold: in (1) systemui and (2) launcher process.
  */
 class ATraceLoggerTransitionProgressListener
-@Inject
-internal constructor(@UnfoldTransitionATracePrefix tracePrefix: String) :
+@AssistedInject
+internal constructor(@UnfoldTransitionATracePrefix tracePrefix: String, @Assisted details: String) :
     TransitionProgressListener {
 
-    private val traceName = "$tracePrefix#$UNFOLD_TRANSITION_TRACE_NAME"
+    private val traceName = "$tracePrefix$details#$UNFOLD_TRANSITION_TRACE_NAME"
 
     override fun onTransitionStarted() {
         Trace.beginAsyncSection(traceName, /* cookie= */ 0)
@@ -43,6 +45,12 @@
     override fun onTransitionProgress(progress: Float) {
         Trace.setCounter(traceName, (progress * 100).toLong())
     }
+
+    @AssistedFactory
+    interface Factory {
+        /** Creates an [ATraceLoggerTransitionProgressListener] with [details] in the track name. */
+        fun create(details: String): ATraceLoggerTransitionProgressListener
+    }
 }
 
 private const val UNFOLD_TRANSITION_TRACE_NAME = "FoldUnfoldTransitionInProgress"